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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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Suggested Citation:"Appendix A - Tools." National Academies of Sciences, Engineering, and Medicine. 2022. Systematic Approach for Determining Construction Contract Time: A Guidebook. Washington, DC: The National Academies Press. doi: 10.17226/26537.
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A-1   A P P E N D I X A Tools CHAPTER 2. CTD GUIDE FOR DESIGN-BID-BUILD PROJECTS T2.1: Project Duration Estimation Methods What Is It? Many departments of transportation (DOTs) have a formal contract time determination (CTD) manual that requires their engineers/schedulers to use a bar chart or critical path method (CPM) to estimate project duration. However, some manuals do not offer information on the strengths and limitations of these two methods. An inexperienced scheduler may not know which method to use given a project’s circumstances. Using an inappropriate method to establish project duration for a project may yield inaccurate estimates. Moreover, these manuals do not include other potential methods that can be adopted in the highway construction industry, such as the linear scheduling method. Therefore, this tool was developed to serve as a comprehensive guide not only for existing methods but also for other potential project duration estimation (PDE) methods. When to Use It? This tool is best to use when a DOT is trying to revise its current guideline/policy on project scheduling. It is also useful when a DOT is trying to explore or to implement a new PDE method. This tool can also be used when a DOT is trying to select a method to calculate the project duration estimate. Why Use It? Currently, no comprehensive guide on project scheduling methods exists that emphasizes transportation projects. This tool was developed after conducting an extensive literature review on CTD manuals from state DOTs as well as academic journal papers. This tool identifies a few potential scheduling methods that can be adopted by the highway construction industry, which include case-based reasoning (CBR), artificial neural network (ANN), and 4D scheduling. These methods were chosen because they have shown promising results in other sectors of the construction industry.

A-2 Systematic Approach for Determining Construction Contract Time: A Guidebook The pros and cons provided by the tool will be particularly helpful for those DOTs that are planning to adopt any of these methods. By understanding the strengths and limitations of each method, DOTs can make a better decision on which method to adopt that will fit best with their current practices and risk tolerance. What Does It Do? In addition to identifying a number of current and potential scheduling methods, detailed information can be found for each method, which includes: • Description of the method. • How the method works. • Strength(s) of the method. • Limitation(s) of the method. • Related studies. How to Use It? The home page lists all PDE methods, including those methods that have the potential to be adopted in the transportation sector. To learn more about a method, click the factor. To view another factor, click “back to home page” (located at the top left corner of each worksheet), and click the method of interest. Tips Users can learn more by looking up the references provided at the end of each worksheet.

Tools A-3   T2.2: Project-Specific Production Rates What Is It? Project-specific production rate is necessary for establishing a reliable estimate of project duration. This necessity requires each DOT to consider the effect of various factors when deciding production rates that are unique to each project. Currently, this process has been primarily based on the professional experience and judgment of DOT schedulers. Not only is that method prone to errors and bias, it also poses a challenge to DOTs when those experienced schedulers are being gradually replaced by new, inexperienced schedulers. Therefore, it is recommended that state DOTs adopt a systematic approach to determining the production rate of each work item based on the unique circumstances of each project. This systematic approach will help DOT schedulers establish a project duration estimate that is both defensible (i.e., supported by logic or historical data) and accurate (i.e., considers project-specific factors). This tool is a summary of how different influential factors on production rate are being considered by state DOTs in the United States. When to Use It? This tool will be a great reference guide when a state DOT is planning to update/revise/develop its production rate database/tool/table. Why Use It? The practice of choosing the appropriate production rate for a work item varies significantly across state DOTs in the United States. DOTs have different supporting tools (e.g., tables, charts, and estimation tools) with varying levels of details. Some DOTs developed sophisticated tools or databases to account for different factors that influence the production rate of a single item. Other state DOTs still rely on a simple production rate table, often with only a single production rate for each work item. Adjustments to production rates are necessary to account for the fact that production rates are not static (i.e., they change based on project conditions). For these DOTs, they will need to see and learn the state of practice of other DOTs in determining the appropriate production rate for a work item based on project characteristics. This tool will help DOTs to evaluate the state of practice, create a benchmark of current practice, and allow DOTs to implement some, if not all, practices as they see fit. What Does It Do? This tool lists 12 major factors influencing production rates: (1) maintenance of traffic, (2) project complexity, (3) coordination with utilities and relocation of utilities, (4) quantities of work, (5) project

A-4 Systematic Approach for Determining Construction Contract Time: A Guidebook phasing, (6) working time restrictions, (7) type of work, (8) overtime and multiple shifts, (9) weather and seasonal effects, (10) location of the project, (11) soil conditions, and (12) legal issues. For each factor, the tool briefly mentions the method currently used by some state DOTs and provides links to access the original DOT sources. How to Use It? 1. Select the factor to consider. 2. The tool identifies how other state DOTs are currently accounting for that particular factor on production rate estimation. 3. To learn more about the practice of a specific DOT, click the link in the rightmost column. It will direct the user to the source of the information (e.g., table, tool, etc.). Example Two examples are provided as follows: Table A-1 and Figure A-1 Table A-1. An example of a production rate table from the Texas Department of Transportation (TxDOT). Note: The Texas DOT has three values of production rates (PRs) for each major work item, including low, medium, and high values. The agency also gives guidance on how to choose the production rate (PR) of an item from the three values based on project conditions. For example, the low PRs are used for the projects that have heavy traffic and complex staging.

Tools A-5   Note: The Montana DOT has a production rate (PR) estimation tool considering district, location type (urban or rural), season of work, project type, engineer’s estimate, and quantity as input variables. Given the input, the tool can generate production rates of 31 controlling activities. Historical measures of production rates are also provided. Figure A-1. An example of production rate tools from Montana DOT.

A-6 Systematic Approach for Determining Construction Contract Time: A Guidebook T2.3: Generic Tool for Production Rate Estimation (GEN- PRET) What Is It? Current practices of production rate estimation vary across DOTs. While some DOTs do not even have state-specific production rates (PRs), the majority of DOTs have tables and charts to support estimating PRs with or without considering specific project conditions. A few DOTs, such as MDT, Wisconsin DOT, and Illinois DOT, have developed advanced automated tools for production rate estimations that not only consider major factors influencing PRs but also facilitate the estimating process. However, these advanced tools are state-specific because they were built upon past project data in those states, and the scope of work of each activity in those tools complies with a specific state’s standard specification. Therefore, those advanced tools cannot be leveraged by other DOTs for their operation. In addition, developing new tools is time consuming and requires specialized expertise in data analytics and machine learning. This generic tool for production rate estimation (GEN-PRET) can be applied by any DOT that maintains or is willing to obtain production rates of past projects to establish a state-specific automated tool for estimating production rates. When to Use It? GEN-PRET can be used during the project duration estimation (PDE) process. Why Use It? GEN-PRET allows for estimating production rates for future projects more systematically and efficiently by considering the main factors that significantly affect production rates of each activity. Furthermore, production rate ranges of similar past projects are provided for double-checking with the estimated production rates. What Does It Do? A DOT can use GEN-PRET to define its own factors influencing a specific construction activity and input corresponding historical data of the activity into the tool. Given the information of a new project, the tool can output the number of past projects that have similar characteristics with the new project, their statistical measures of production rates (i.e., mean, median, first quartile, and third quartile), and two production rate estimates using two methods: linear regression and case-based reasoning.

Tools A-7   How to Use It? Steps for tool development: 1. In the “Historical Data” sheet, input the highway agency name, activity description, and unit of measurement. Each Excel file corresponds to a construction activity. 2. Identify the factors that influence the production rate of the activity, including factor name, variable name, and variable coding (e.g., 1 = urban project and 0 = rural project). 3. Input the corresponding historical data of the activity. Steps for applying the tool for a new project: 1. Type in the values of the input variables (defined in Step 2) for a new project. 2. Decide whether an input variable is considered in the estimation by checking or unchecking the corresponding box. 3. GEN-PRET will output the number of similar past projects, statistical measures of production rates of the similar projects, and the estimated production rates for the activity using linear regression and case-based reasoning. Tips • GEN-PRET is a Microsoft Excel-based tool that requires Excel macros to be enabled. • Only enter values in gray cells.

A-8 Systematic Approach for Determining Construction Contract Time: A Guidebook T2.4: Influential Factors on Project Duration Estimation and Contract Time Determination What Is It? The majority of DOTs have a formal contract time determination (CTD) manual that lists influential factors on project duration estimation (PDE) and/or CTD. However, the listed factors vary significantly among DOTs and are not comprehensive. In addition, most of the CTD manuals do not provide details about the effects of the factor on contract time. This tool was developed to offer a comprehensive list of influential factors and a detailed description of each factor. When to Use It? This tool can be used during the process of determining contract time or as a checklist before submitting the contract time for approval and letting. This tool may also come in handy when evaluating the schedule risk of a project in a risk workshop during the early stages of the project development process. Why Use It? A realistic contract time cannot be established without considering most, if not all, factors that could affect the contract duration. Leaving out factors during the CTD process might produce an overly optimistic contract time, which would result in underestimation of both the road user impact and the construction cost initially estimated by the contracting agency. Although these influential factors may seem trivial to veteran DOT schedulers, inexperienced DOT schedulers may not have sufficient work experience to confidently pinpoint every single factor that will affect a project’s contract time. This tool is expected to reduce the possibility of an influential factor being unintentionally neglected during the CTD process. What Does It Do? This tool provides a comprehensive list of factors that have been identified as influencing PDE or CTD. It also provides a brief overview or a related literature review of each factor. How to Use It? The home page lists 42 factors influencing PDE/CTD. To learn more about a factor, click the factor (on the home page), and the tool will take the user to the corresponding worksheet that contains detailed information on the selected factor. To view another factor, click “back to home page” and then click the next factor of interest.

Tools A-9   To use this tool as a checklist, evaluate whether each factor has been considered in the CTD and perform the following: • Select “Yes” to indicate the factor has been accounted for. The factor will then be highlighted in green. • Select “No” if this factor is applicable to the project under consideration but has not been considered. The factor will be highlighted in red, indicating further action is required. • Select “N/A” if this factor does not apply to the project under consideration. Use this option only if certain that the factor does not apply. Tips • Users can learn more by looking up the references provided at the end of each worksheet. • For best practice, it is recommended to submit the home page of this tool (after checking the status of each factor) along with the contract time estimate. All factors should be colored in green or white (i.e., no red boxes).

A-10 Systematic Approach for Determining Construction Contract Time: A Guidebook T2.5: From PDE to CTD (PD2CT) What Is It? In current practice, DOTs typically establish contract time by first calculating the number of working days and then manually convert that number into contract time if the contract time needs to be expressed as the number of calendar days or as a completion date. Some DOTs apply a conversion factor(s) based on historical data, while some DOTs use a contingency factor to account for non-working days. This conversion process is often not systematic and differs by administrative districts, thus affecting the accuracy of the conversion. The “From PDE to CTD” tool (PD2CT) helps determine contract time given a project duration estimate in working days. The primary function of PD2CT is to help DOTs do the conversion systematically and accurately while considering multiple factors that influence contract time, which is Step 4 in the overall CTD procedure for traditional DBB projects, proposed in Chapter 2. Moreover, it supports Step 2 (Determine Constraints), Step 3 (Select Contract Time Type), and Step 5 (Determine Contract Time). When to Use It? PD2CT can be used in different project development phases when schedulers have estimated project duration in working days and need to convert it into calendar days or determine a contract time from it. However, it is particularly useful at the end of the final design or the plans, specifications, and estimates (PS&E) stage when CTD is performed. In addition, users will find PD2CT more useful when they have information about the schedule requirements of the project under consideration, such as estimated letting date, expected working calendar, schedule constraints, applicable holidays, and the like. Why Use It? There is a lack of effective supporting tools that can integrate PDE, completion date constraints, constraints on non-working days, and other related factors to come up with a final contract time. PD2CT systematically calculates the possible contract time by considering several factors that have been identified to influence contract time. PD2CT also allows DOT schedulers to quickly assess the impact of delayed letting dates on contract time. What Does It Do? Using PDE as the input, PD2CT calculates the contract time of a project by incorporating the effects of a number of factors that include: • Different workday calendars (e.g., standard five-day weeks, seven-day weeks, and night work). • Different combinations of holidays. • Different scenarios of adverse weather days.

Tools A-11   • Shutdown periods and specific non-working days. • Constraints on the completion date. With the additional input of the required number of working days and an assumed earliest start date, PD2CT will output a corresponding completion date, the number of calendar days, and whether the completion date satisfies the completion date constraints. The tool will also output the results for one-week to eight-week later start dates so that DOTs can see the effect of the start date on contract time. How to Use It? 1. Enter the following information: o Earliest contract (construction) start date. o Number of working days (i.e., PDE). 2. To use the constraint checking function, enter the required completion date (i.e., date that your agency wants the project finished by) for each applicable category. 3. Answer some relevant questions to select the contract time type. If working day is the type of contract time, the conversion from working days to calendar days is not necessary. Otherwise, continue with the following steps. 4. Enter relevant information to describe the workday calendar(s) that applies to the project under consideration: o The tool can accommodate up to three different types of workday calendars for three consecutive periods of time. o For each period, enter its start date, and select one type of calendar. 5. If necessary, enter the adjustment factor to account for reduced or increased productivity during a particular period. 6. Select all holidays (non-working) that are recognized by the agency. 7. Enter the monthly anticipated non-working days caused by adverse weather conditions. 8. Enter any applicable non-working periods. 9. Enter any other specific non-working days. 10. Click on “CLICK HERE TO GO TO THE NEXT STEPS” to obtain the contract time in the fixed completion date or calendar days and see whether the contract time satisfies the inputted completion date constraints. Tips • PD2CT requires Excel macros to be enabled. • Only enter values in gray cells. • If work is permitted during winter months, then those non-working days caused by extreme winter conditions should be accounted for in the monthly adverse weather day table. Do not enter the winter season as a non-working period because that directive tells the program not to allow any work during this period.

A-12 Systematic Approach for Determining Construction Contract Time: A Guidebook T2.6: Montana DOT’s Production Rate Estimation Tool (MDT-PRET) What Is It? Highway construction involves activities that are heavily affected by a number of operational and environmental conditions, so conventional production rate estimation methods, such as expert opinion, engineering judgment, and production rate charts, have limitations. One of the main limitations is that unique project factors and site conditions are very difficult to consider quantitatively. Developed by a group of researchers from Iowa State University, MDT-PRET is a Microsoft Excel tool that automatically generates production rate estimates for major controlling activities by using regression models developed from daily work report data. When to Use It? This tool can be used during the project duration estimation (PDE) process. The following information about a project must be known before using this tool: location, project type, engineer’s estimate, quantities of work, and anticipated construction season. Why Use It? MDT-PRET allows MDT engineers to estimate production rates for future projects more systematically and efficiently by considering the main factors that significantly affect production rates of each controlling activity. Because this tool is based on statistical relationships found between the production rates and various factors from the daily work report data, MDT personnel can obtain more accurate and realistic estimates of production rates. What Does It Do? MDT-PRET is a tool that generates production rate estimates for major controlling activities of highway projects. It serves as a quick tool to estimate production rates of work items using key project parameters, such as project location, project type, engineer’s estimate, and quantity of work. This tool also helps determine a possible production rate range for each controlling activity based on mean, first quartile, median, and third quartile values. How to Use It? For more detailed instructions, please refer to the user manual of this tool (see Tips). 1. Open the tool and click “Launch Tool” in the “Introduction” sheet. 2. Enter the five required inputs shown in the “Input Screen” sheet and then click “Next.”

Tools A-13   3. Enter the quantities of controlling activities relevant to the project in Column D of the “Production Rate Estimates” sheet. 4. Click “Show the Estimated Production Rates” to generate predictions in Column E. Tips • MDT-PRET is a Microsoft Excel-based tool that requires Excel macros to be enabled. • When entering quantities in the “Production Rate Estimates” sheet, make sure that the values entered in Column D correspond to the units given in Column C. • To view historical production rates, click the “View Historical Production Rates” button on the “Production Rate Estimates” sheet. • To save the production rate estimate table in a PDF file, click the “Save as PDF” button at the bottom right corner of the “Production Rate Estimates” sheet. • The “Return to Input Menu” button allows users to go back to the “input screen” sheet to change the input parameters as needed. • To learn more about the research behind this tool, visit the following URL: https://www.mdt.mt.gov/research/projects/const/production_rates.shtml • Download the user manual of this tool at https://www.mdt.mt.gov/other/webdata/external/research/DOCS/RESEARCH_PROJ/PRODUCT ION_RATES/PRET_USERS_MANUAL.pdf

A-14 Systematic Approach for Determining Construction Contract Time: A Guidebook T2.7: Wisconsin DOT (WisDOT) Productivity Estimation Tool (PET) What Is It? Using project-specific production rates is crucial to establish an accurate duration for each work item in a highway project. Traditionally, WisDOT engineers can only rely on the production rates published in their Facilities Design Manual (FDM) to estimate the project duration. However, these production rates are not frequently updated, and they do not consider the unique attributes of each project. In rectifying the situation, the prototype (first) version of a productivity estimation tool (PET) was developed by WisDOT in 2013. The tool featured herein is the second version of PET, which was revised and improved upon by Brent T. Flaten in 2015. It is currently a Microsoft Excel-based tool designed to help WisDOT engineers and designers quantitatively predict and estimate highway construction productivity rates for future projects. When to Use It? This tool can be used during the project duration estimation (PDE) process. In order to generate project-specific production rate estimates, this tool requires a user to have a considerable amount of knowledge about the project under consideration, such as design attributes, staging requirements, the scope of work, specifications, and more. Why Use It? This tool can predict production rates based on a consideration of the specific circumstances of a project. Depending on the construction activity, approximately 15 project factors are considered in this tool. User-friendliness has also been significantly improved in this second version of the tool because it now features an enhanced visual means of displaying productivity information. The estimated value is shown in a box-and-whisker plot, allowing the user to easily extract more productivity information (i.e., historical production rates) and to make an appropriate judgment of the predicted values if necessary. What Does It Do? WisDOT’s PET considers a variety of design project attributes and input parameters entered by WisDOT construction staff to estimate production rates for major work items. The tool has production rates broken into five categories: (1) asphalt paving, (2) bridges, (3) concrete paving, (4) earthwork, and (5) miscellaneous. It uses linear regression to estimate production rates on future projects.

Tools A-15   How to Use It? For more detailed instructions, please refer to the user guide of this tool (see Tips). 1. Read the instructions on the “Introduction” tab, then select the “Launch Tool” button at the bottom of the page. 2. On the “Main Menu” tab, select the appropriate project type. 3. On the input tab, for each factor, enter the rating (i.e., severity) that best describes the project under consideration. 4. Click “Get Estimated Productivity Rates” at the bottom of the user input page. 5. On the Output tab, depending on the type of activity, productivity information is shown in two different formats. 6. For non-modeled activities (insufficient data to conduct regression), only the minimum value, average value, and unit of measurement are given. 7. For each of the modeled activities (sufficient data to conduct regression), users will find the minimum value observed, value predicted by the tool, maximum value observed, and unit of measurement. These values will be displayed both in tabular format as well as in graphical form (e.g., box-and-whisker plot). Tips • To learn more about the development of this tool, visit the following URL: http://digital.library.wisc.edu/1793/75456 • A user guide of this tool can be found in Appendix E of the following document: http://digital.library.wisc.edu/1793/75456 • To download this tool, visit the following page: http://wisdot- productivity.engr.wisc.edu/home/section-6 • To learn more about WisDOT’s practice in determining contract time, visit WisDOT’s FDM, Chapter 19: Plans, Specifications, and Estimates, Section 10: PS&E Transmittal and Composition, Subsection 30: Contract Time for Completion (DT 1923). Link: https://wisconsindot.gov/rdwy/fdm/fd-19-10.pdf#fd19-10-30

A-16 Systematic Approach for Determining Construction Contract Time: A Guidebook CHAPTER 3. CTD GUIDE FOR URBAN PROJECTS WITH INCENTIVE PROVISIONS T3.1: CA4PRS What Is It? Transportation agencies have attempted to deliver projects in a more timely manner using alternative contracting techniques (ACTs) since 1990 (FHWA 2016). Various tools have been developed to assist agencies in contract time determination (CTD) for projects contracted with ACTs. A more recent tool arising from these efforts is a state-of-the-art tool called Construction Analysis for Pavement Rehabilitation Strategies (CA4PRS), which has come into use because of its integrative ability to analyze schedules, costs, and work zone traffic impacts. CA4PRS was developed under FHWA-pooled fund research through a multistate consortium (California, Minnesota, Texas, and Washington). CA4PRS software is a scheduling and work zone impact analysis tool used to select the most economical strategies for highway rehabilitation or reconstruction given various project constraints. When to Use It? This tool is used to determine the contract time during the planning phase of program (project) development. The use of CA4PRS can be beneficial for transportation agencies when it is implemented during the planning and design stages of highway project development in order to determine accelerated project schedules with ACMs while minimizing traffic delay to the public. Why Use It? According to the updated federal regulations in Rule 23 CFR Part 630 Subpart J regarding safety and mobility in work zones (FHWA 2007), all state and local governments that receive federal-aid highway funding must now implement transportation management plans (TMPs). CA4PRS can perform the majority of the analyses required for compliance with the new federal rule. Although other similar tools exist, they may not be able to for the following reasons: • Level of complication for routine DOT analyses. • Group license acquisition cost. • Time needed to obtain the required inputs information. The CA4PRS tool is effective at evaluating the effects of different traffic control options on contract time, road user cost, and level of traffic inconvenience. At the same time, CA4PRS is lightweight, self- sufficient, and free to use because FHWA has already arranged licenses for all state transportation agencies. As a result, there has been growing acceptance of the program nationally, and it is already widely used in California and four other states.

Tools A-17   What Does It Do? CA4PRS has a user-friendly interface. The CA4PRS scheduling module calculates the duration of the project in terms of the total number of closures and closure hours required for each rehabilitation alternative. Using a demand-capacity model based on the Highway Capacity Manual, the CA4PRS traffic module quantifies the impact of work zone closures on the traveling public in terms of time spent in the closure and road user cost. How to Use It? CA4PRS can help develop sound transportation management plans that account for the integration of schedule and traffic impact that the work zone will have on the traveling public. Because the scheduling reliability and accuracy of CA4PRS were validated with numerous highway renewal projects, it is assumed that the program’s use will provide reliable baseline data. Typical analysis procedures in CA4PRS are as follows: • Input the scope (lane miles) of the rehabilitation project. • Select a rehabilitation strategy: PCC reconstruction, CSOL rehabilitation, or FDAC replacement analysis modules. • Define a new pavement cross section: slab and base thickness (PCC) or layer profile (AC). • Set concrete curing time (PCC) or AC cooling time (or let the MultiCool software calculate cooling times interactively). • Choose a construction window (closure timing and length): for example, 10-hour nighttime closure only, 55-hour weekend closure, or 72-hour weekday closure. • Select rehabilitation sequences and lane closure tactics. • Input the contractor’s logistical resources (crew, equipment, and plants) for major operations. • Perform a schedule analysis. • Input the duration of the project in the traffic analysis module. • Set the traffic parameters, including closure length, construction year, lane closure tactic, speed limit, traveler’s value of time, truck percentage, and average traffic volume. • Perform a traffic analysis. For more detailed information about its usage, please refer to FHWA’s CA4PRS training page at http://ops.fhwa.dot.gov/wz/p2p/ca4prs/presentations/training/index.htm. Example Since 1999, the capabilities of CA4PRS have been confirmed through several major highway rehabilitation projects in California, Washington, Minnesota, and Texas. Validation studies on several major highway rehabilitation projects in California, Washington, and Minnesota have proven the reliability and accuracy of the software. For Example 1, CA4PRS was used to select the most economical rehabilitation scenario for the I-15 Devore Project in Southern California, optimally balancing contract time, road user cost, and the level of traffic inconvenience (see Table A-2).

A-18 Systematic Approach for Determining Construction Contract Time: A Guidebook Table A-2. CA4PRS results for the I-15 Devore project near Los Angeles by Caltrans. For Example 2, CA4PRS was used to estimate the schedule and road user delay costs for four rehabilitation scenarios for the I-45 Houston Project in Texas, providing project engineers critical information for decision-making (see Figure A-2). Figure A-2. CA4PRS results for the I-45 Houston project. For more examples, see the Caltrans CA4PRS website at http://www.dot.ca.gov/newtech/roadway/ca4prs.

Tools A-19   Tips CA4PRS can help agencies prepare strategies (including the PS&E package) for highway projects by: • Estimating working days and CPM schedules. • Developing construction staging plans. • Supplementing traffic management plans. • Outlining incentives for ACT projects. Because FHWA has purchased a group license of CA4PRS, all 50 state DOTs have an unlimited free license for the CA4PRS software for their internal use. It is downloadable at http://www.dot.ca.gov/newtech/roadway/ca4prs/protected/index.htm. References FHWA. 2016. Special Experimental Projects No. 14—Alternative Contracting. Federal Highway Administration. Accessed March 7. https://www.fhwa.dot.gov/programadmin/contracts/sep_a.cfm.

A-20 Systematic Approach for Determining Construction Contract Time: A Guidebook T3.2: Primavera P6 What Is It? Primavera P6 is designed to handle large-scale, highly sophisticated, and multifaceted projects. It can be employed to organize projects with up to 100,000 activities, and it provides unlimited resources and an unlimited number of target plans (Oracle 2015). P6 allows state DOTs to have a better comprehensive view of the project plan at the preconstruction stage prior to letting. It provides a tool for holding the contractor accountable to that plan. It can manage multiple projects with an unlimited number of tasks while improving communication and facilitating decision-making. According to TxDOT engineers and other agency practitioners, adopting P6 takes time and training commitment to gain proficiency. For this reason, many state DOTs, including TxDOT, have utilized outside consultants in addition to in-house experts. When to Use It? This tool is used to develop and optimize scheduling, analyze risks, and estimate contract time with high fidelity for complex projects. The use of P6 for the project can be beneficial for determining a highly optimized and well-thought contract time before letting after most of the design is finished. Why Use It? Primavera P6 has been widely used across 16 states, which are Arizona, Connecticut, Florida, Illinois, Massachusetts, New Jersey, New Mexico, New York, Puerto Rico, South Carolina, South Dakota, Texas, Utah, Virginia, Washington, and Wyoming (Arizona DOT 2012; Minnesota DOT 2010; Utah DOT 2012; Wyoming DOT 2015). The primary driver for various state DOTs to use P6 is the desire to improve on existing applications. The South Carolina DOT adopted P6 because they found that P6 would resolve some of the problems they were having with P5. The Texas DOT had used Primavera for construction management in past years and decided to adopt P6 when the department moved into preconstruction management. The Port Authority of New York and New Jersey and Connecticut, Florida, and New York state DOTs moved to P6 because they were existing Primavera users with maintenance agreements that included upgrades to the latest version of the product. In the majority of state DOTs including the Texas DOT, the business division holds primary responsibility for managing P6 (Khwaja 2011; Minnesota DOT 2010). What Does It Do? For transportation agencies, Primavera P6 is used for prioritizing, planning, managing, and evaluating projects, programs, and portfolios. P6, developed by Oracle, is an integrated cloud-based software-as-a- service solution for project portfolio management. With P6, the project team can manage resource scheduling and project performance. P6 is also a tool for risk management, with comprehensive analytical modules that enable robust planning of complex projects. Last, P6 provides both progress tracking to manage cost and resource use and interfaces to record and analyze project performance to help improve the quality of future decision-making.

Tools A-21   How to Use It? Primavera P6 can be a powerful tool in developing well-devised scheduling and resource allocation plans for large complex transportation projects, which many urban projects are. The comprehensive project schedule management capability of P6 is beneficial in estimating accurate project duration for effective CTD. To make the best use of P6 for transportation agencies, the following procedures are recommended for implementation (Khwaja 2011): • Develop a clear understanding of the policy goals and administrative objectives for CTD procedures. • Communicate the objectives and benefits of implementing P6 on CTD to various internal stakeholders (i.e. local agencies). • Identify business processes across all stakeholders involved in the project development. • Develop standardized P6 templates for each type of business process and project scenario. • Develop standardized procedures for project scheduling and CTD based on the needs and functional requirements of each scenario. • Develop reporting standards for project schedule information and project portfolio management. • Develop standardized training program and provide technical support during the implementation of P6. • Develop project data storage plan to ensure the integrity and security of the project portfolio data. • Identify technical constraints and find solutions to maintain the effectiveness of P6 implementation. Example There are a wide variety of use cases for P6. For example, P6 has been implemented by Minnesota DOT (MnDOT) as the main project duration estimate tool to manage schedules for road and bridge construction projects for scoping, design, and construction contract administration. P6 has been a critical element in delivering projects on time via its powerful CPM and schedule management. Because of their successful implementation of P6 on large projects, MnDOT decided to expand its implementation to local projects. See more details at http://dotapp7.dot.state.mn.us/eDIGS_guest/DMResultSet/DisplayDoc?docnumber=1696040&noframes= yes. Tips P6 is a tool for project scheduling and management. Its capabilities include streamlining complex processes and standardizing CTD procedures. State DOTs need to carefully design and develop P6 templates based on policy goals and objectives and then provide training to various local transportation agencies in order to help them establish the workflow that provides the most benefit to them. References Arizona DOT (2012). “Project Management Services.” Accessed 03/13. http://azdot.gov/business/ManagementServices/ProjectResourceOffice/scheduling-tools-and- documentation.

A-22 Systematic Approach for Determining Construction Contract Time: A Guidebook Khwaja, N. (2011). Implementing a Project and Portfolio Management System for TxDOT Project Development. Center for Transportation Research, University of Texas at Austin. Minnesota DOT (2010). “State DOT Experiences with Primavera P6 Project Management Software.” Accessed 03/13. http://www.dot.state.mn.us/research/TRS/2010/TRS1005.pdf. Oracle (2015). “Primavera P6 Professional Project Management.” Accessed 03/13. http://www.oracle.com/us/primavera-ppm-brochure-070808.pdf. Utah DOT (2012). “Prosecution and Progress.” Accessed 03/13. www.udot.utah.gov/main/uconowner.gf?n=7577628238658999. Wyoming DOT (2015). Construction Manual. Accessed 03/13. http://www.dot.state.wy.us/files/live/sites/wydot/files/shared/Construction/2015%20Construction %20Manual/2015%20Construction%20Manual.pdf.

Tools A-23   T3.3: QuickZone What Is It? QuickZone is a user-friendly, spreadsheet-based traffic analysis tool developed by FHWA. It is capable of analyzing work zone mobility impacts such as traffic delays, queuing, and road user cost (RUC). The tool uses a link-node network system with a deterministic delay estimation to analyze the traffic impact of a work zone on an existing traffic network. When to Use It? QuickZone is used to calculate traffic delays and evaluates how modifying a schedule can affect traffic delays. It is best to use QuickZone after construction alternatives have been proposed for a project to estimate the traffic impact of each alternative and get a general idea of the project schedule. Why Use It? To determine a contract time that can provide the most benefit to the traveling public, transportation agencies need to estimate not only an accurate project duration but also traffic delay. QuickZone is proven to be an effective tool to mitigate congestions due to work zones, including high-volume urban projects with recurring congestion problems. Because of its effectiveness, QuickZone has been adopted by several states, including Iowa, Missouri, New Hampshire, and New York, and the District of Columbia. What Does It Do? QuickZone is capable of both project duration and traffic delay estimates. It can be used to (FHWA 2017): • Quantify corridor delay resulting from capacity decreases in work zones. • Identify impacts of delays in alternative project-phasing plans. • Support trade-off analyses between construction costs and delay costs. • Examine the impacts of construction staging by location, time of day (peak versus off-peak), and season (summer versus winter). • Assess travel demand measures and other delay mitigation strategies. • Help establish work completion incentives. How to Use It? QuickZone calculates the average traffic delays and maximum queue lengths resulting from lane restrictions in urban and suburban work zones. The software uses standard deterministic queuing theory and volume-capacity ratios to estimate traffic delays, which requires the following data input (Abdel- Rahim et al. 2010):

A-24 Systematic Approach for Determining Construction Contract Time: A Guidebook • Data on the roadway facility under construction and adjacent alternative routes in the travel corridor. • Data on the work zone strategy and phasing plan, including anticipated capacity reductions due to the work zone. • Data on travel demand, including travel patterns in the corridor prior to construction. • Data on planned strategies to mitigate congestion during each construction phase, including estimates of capacity changes. For more information, please visit FHWA documentation of QuickZone: https://ops.fhwa.dot.gov/wz/traffic_analysis/quickzone/. Example I-95 Operational Analysis for Lane Closures at Night—Maintaining roadway capacity is an important aspect in the ongoing Woodrow Wilson Bridge replacement project in the Washington, DC, metropolitan area. Project engineers conducted a QuickZone analysis with multiple scenarios for extending the lane closure duration time and the number of lanes closed. Consequently, total duration of the construction project was reduced from an estimated 6 months to 2 months. More details of this example project can be found at https://ops.fhwa.dot.gov/wz/traffic_analysis/quickzone/casestudies/snapshot2.htm. Tips As an open-source Excel-based tool, QuickZone allows for further customization to provide state and local DOTs with specific functionalities suited to their needs. References Abdel-Rahim, A., Cooley, H., Gould, S., and Khanal, M. (2010). Synthesis of Research on Work Zone Delays and Simplified Application of QuickZone Analysis Tool. Idaho Transportation Department. Accessed 06/20. http://idahodocs.cdmhost.com/cdm/ref/collection/p16293coll3/id/241107. FHWA (2017). “Work Zone and Traffic Analysis Tools—QuickZone.” Accessed Mar 27. https://ops.fhwa.dot.gov/wz/traffic_analysis/quickzone/.

Tools A-25   T3.4: CO3 What Is It? The Construction Congestion Cost System (CO3) is an integrated set of tools to estimate the impact of traffic maintenance contract provisions on congestion, road user cost, and construction cost (Carr 1997; Carr 2000). CO3 is implemented in a Microsoft Excel spreadsheet. It models the circular relationship between work zone demand and delay to estimate traffic congestions and road user cost around work zone (Carr 2000). When to Use It? Project engineers can use CO3 to produce realistic budgets and select practical contracting methods that provide an acceptable balance between construction cost and congestion (Carr 2000). This tool can be used during the design phase to help design engineers compare road user costs and construction costs of project alternatives and select the best alternative. Why Use It? For complex urban projects with high traffic volume, design engineers need to compare user costs and construction costs of alternative contract provisions to help them select the best project alternative. Therefore, CO3 helps engineers select among alternative methods of maintaining traffic during construction, and it helps them select contract period costs for contract provisions that provide incentives for reducing congestion impacts during construction. What Does It Do? CO3 models the relationship between traffic demand and traffic delay around a work zone. In this model, detour and trip cancellations are based on traffic delay, traffic demand is a function of detour and trip cancellations, and traffic delay is determined by work zone demand and road capacity. This model considers traffic as an integrated stream of two classes of vehicles—trucks and cars—that share backups but differ in diversion and cancellation sensitivity. Based on the model, CO3 calculates traffic delay and queuing caused by traffic demand that exceeds road capacity around the work zone (Carr 2000). How to Use It? CO3 needs the following input information to estimate traffic delay: • Traffic demand and annual growth rate. • Road user cost per hour and per cancellation. • Road capacity and lane closure. • Work zone length, detour distance, and travel speed. References Carr, R. I. (1997). Construction Congestion Cost—CO3 User Manual. Dept. of Civ. and Engrg., Univ. of Michigan, Ann Arbor, MI. Carr, R. I. (2000). “Construction congestion cost (CO3) basic model.” Journal of Construction Engineering and Management, 126(2), 105–113.

A-26 Systematic Approach for Determining Construction Contract Time: A Guidebook T3.5: KY-CTDS What Is It? KY-CTDS is a regression-based contract time determination (CTD) tool developed by the Kentucky Transportation Cabinet (KYTC). The tool was developed through regression modeling that uses historic data (Taylor et al. 2013). When to Use It? KY-CTDS is an ideal tool for engineers to use as a starting point during the project planning phase to obtain a baseline estimate of contract time, before consulting experienced personnel to refine the number of working days. Why Use It? KY-CTDS is a spreadsheet-based tool that is very easy to use and requires only basic project information (such as budget and project type) to quickly estimate project durations with fairly good accuracy. What Does It Do? In KY-CTDS, there are two different systems for projects below and above a $1 million budget, respectively. For small projects (less than $1 million), KYTC discovered that bid item quantities did not impact contract time for small projects. As a result, other factors, such as project type or the feasibility to complete within 9 months, are used to determine the contract time. For large projects (over $1 million), a parametric tool based on bid item quantities and subcategories of the project is used to determine the contract time. How to Use It? For small projects (less than $1 million), input project type, season, and construction cost estimate to calculate the schedule estimate. For projects larger than $1 million, the tool provides five types of regression estimators for different types of projects. Select the corresponding estimator and then input the required project information, such as construction cost or pavement quantity, to get the project duration mean value with a confidence interval. Tips For both small projects and projects over $1 million, a careful review by experienced engineers is required to finalize the contract time, and KY-CTDS has limited accuracy for smaller projects. References Taylor, T., Goodrum, R. M., Brockman, M., Bishop, B., Shan, Y., Sturgill, R. E., and Hout, K. (2013). “Updating the Kentucky Contract Time Determination System.”

Tools A-27   T3.6: Illinois Construction Scheduling Expert System What Is It? The Illinois Construction Scheduling Expert System (ICSES) was designed to develop the estimate of time required for typical highway construction project types for the Illinois Department of Transportation (IDOT). The tool references the Standard Specifications for Road and Bridge Construction in Illinois and Illinois climate data. The scheduling tool uses production rates from the IDOT Bureau of Design and Environment (BDE) Manual, Chapter 66, supplemented with guidance derived from a variety of reference sources (Slattery et al. 2011). When to Use It? ICSES is designed to develop an estimate of time required for typical highway project types. It is best to use ICSES after construction alternatives have been proposed for a project and then estimate the traffic impact of each alternative and get a general idea of the project schedule. Why Use It? ICSES was developed by Illinois Center for Transportation in response to the need by IDOT for more accurate highway construction schedules. ICSES’s functionality successfully assists design engineers in working on IDOT projects to develop better estimates of time, which benefits the traveling public by potentially reducing lengthy construction impacts and costs. What Does It Do? ICSES is a Windows-based software tool that captures highway construction scheduling knowledge from contractors, design engineers, resident engineers, consultants, and historical project records. It can develop an estimate of project duration based on historical production rate records, climate data, and input of project activity items. The tool is capable of generating estimates for various project types in highway construction and rehabilitation (Slattery and Slattery 2015). How to Use It? To generate estimates of project duration, ICSES needs the following inputs: • Project type and project activities template (can be modified from default templates). • Project scope and item quantities. • Project start date and workday calendar. • Project constraints, such as utility relocations, permits, and critical lane uses. Once all these inputs are provided to ICSES, a preliminary bar chart schedule will be estimated. Engineers can then evaluate the schedule in detail and finalize the schedule report for further CTD procedures.

A-28 Systematic Approach for Determining Construction Contract Time: A Guidebook For more information, please visit IDOT documentation of ICSES: http://www.idot.illinois.gov/Assets/uploads/files/Doing-Business/Manuals-Guides-&- Handbooks/Highways/ICSES/ExpertSystemUserManual03_01_2015.pdf. Tips This tool was developed specifically for IDOT and references production and climate historic records particular to Illinois. References Slattery, D. K., and Slattery, K. T. (2015). “Enhancements to Highway Construction Scheduling Expert System (Including User Manual).” Illinois Center for Transportation/Illinois Department of Transportation. Slattery, D. K., Slattery, K. T., and Bruce, R. D. (2011). “An Expert Systems Approach to Highway Construction Scheduling.”

Tools A-29   CHAPTER 4. CTD GUIDE OF ALTERNATIVE PRR OJECT DELIVERY METHODS T4.1: Preconstruction Activity Duration Checklist What Is It? Realistic activity duration is the key to creating an accurate schedule. The duration of various construction activities has been extensively studied. Using historical work data, it is now possible to obtain a reasonably accurate estimate for certain construction activities. However, this exhaustive study is not the case for preconstruction activities. The process of determining the duration of a preconstruction activity is often subjective and primarily based on rules of thumb. Because of the absence of quantitative supporting data, the importance of identifying potential issues that will influence the duration of preconstruction activities becomes more pronounced. This tool serves as a risk checklist that offers a list of factors that can potentially influence the duration of preconstruction activity. When to Use It? This tool can be used during the contract time development process of a project, particularly when estimating the preconstruction duration of projects using alternative project delivery methods. Why Use It? Unlike construction activities, it is much more challenging to estimate the duration of preconstruction activities. The challenge is the unavailability of production rates for most preconstruction activities. This factor makes the duration estimation of preconstruction activity more reliant on rules of thumb established from past experiences. Nonetheless, these rules of thumb often have a wide margin and are meant for “typical” project circumstances. A rule of thumb may serve as a great starting point for duration estimation, but it starts to fall short when a scheduler tries to pinpoint a specific duration value. Also, preconstruction activity duration is highly dependent on a plethora of factors, such as the level of design completed prior to advertisement and permitting requirements. For example, the design submittal review time may need to be extended if there is an insufficient number of in-house designers/engineers in a state DOT. What Does It Do? This tool contains a list of questions (and some tips) that will help a DOT engineer/scheduler gain a better understanding of the requirements and status of a project that has preconstruction duration included in its contract time. The increased level of understanding about a project allows DOT schedulers to establish a reasonable and realistic duration that corresponds to the level of risk of each preconstruction activity. How to Use It? Carefully review each bullet point in this tool. Jot down responses, if needed. Make sure to incorporate the response to each relevant question into the duration estimate of the corresponding preconstruction activity.

A-30 Systematic Approach for Determining Construction Contract Time: A Guidebook T4.2: Preconstruction Period Estimation Tool What Is It? Alternative project delivery methods, such as design-build (DB), combine both design and construction work into a single contract. Thus, the contract time of these projects includes not only the duration required for construction activities but also the duration for preconstruction activities (e.g., design, permitting, ROW acquisition). The preconstruction period is the time needed to complete necessary design deliverables and other preconstruction activities (e.g., permits acquisition, ROW acquisition) that will allow the first work package to be released for construction (RFC). It is imperative to understand that the preconstruction period is not the amount of time it takes to complete the final design. This tool is designed to guide DOT schedulers in systematically developing a preconstruction schedule and, subsequently, a preconstruction duration estimate that is project-specific and risk-appropriated. When to Use It? This tool can be used during the contract time development stage of a project, particularly when a state DOT is trying to estimate the preconstruction duration of a project using alternative project delivery methods. Why Use It? Establishing a preconstruction period is not easy because it does not include all preconstruction activities. The DB method is often only used by DOTs to deliver projects containing special circumstances, so it is nearly impossible to offer a reliable rule of thumb on the length of the preconstruction period. The length of this period also greatly depends on the amount of work involving the first work package, which varies significantly between projects. To make matters worse, a limited number of tools and guidance currently exists for establishing a preconstruction period for contract time determination (CTD) purposes. Some DOTs, particularly those who are new to alternative project delivery, may find it challenging to determine an appropriate duration for the preconstruction period due to overlap between design and construction activities in a DB project. This tool offers step-by-step guidance to determine the preconstruction period of a DB project. What Does It Do? This tool is comprised of a total of five worksheets: the “READ ME—General Instructions” sheet and four other sheets that correspond to the four steps required to establish a preconstruction period. Apart from the “READ ME” sheet, each remaining worksheet has an “Instruction” box that clearly outlines the specific tasks that a user needs to complete for each step. Some sheets may also have a “Note” box that offers additional guidance and tips for the specific step.

Tools A-31   The first step will help users to identify design work packages that need to be included in the preconstruction period. Then, users will list out major preconstruction activities associated with each of the preconstruction work packages, as well as any milestones that will constrain the preconstruction schedule. Based on a user’s input, the third step will calculate a risk-adjusted duration for each preconstruction activity using a 3-point estimating procedure. Finally, the user will develop a preconstruction schedule based on activities and corresponding duration estimates established in previous steps. This preliminary schedule will be adjusted as necessary based on the milestones identified earlier. How to Use It? For more detailed instructions, please refer to the instructions provided within the tool. 1. Carefully review the “READ Me—General Instructions” tab. Then, click the button “Click to START.” 2. In 1—Design Work Package, for each suggested work package, examine whether any of the two statements applies: a. Check the C column if the work package will be complete when the project is advertised. b. Check the D column if the work package cannot be RFC until after the notice to proceed (NTP) of the overall construction. c. Leave both C and D unchecked if both statements do not apply. d. Based on the user’s input, the tool will automatically determine whether a work package needs to be included in the preconstruction period. 3. In 2—Precon Activities & Milestones, in Table 2-2 within the tool, list the activities required to complete each preconstruction work package listed in Table 2-1. In addition, list out all milestones that will constrain the preconstruction schedule in Table 2-3. 4. In 3—Precon Activity Duration, for each preconstruction activity, estimate its duration in three different scenarios—best (shortest duration), most likely, and worst (longest duration). Please complete Table 3-2 (ACM Issue Impact Checklist) within the tool. For each issue type, check any statement that applies to the project. Assign an issue type to each preconstruction activity using the dropdown menu. The tool will then automatically generate a risk-adjusted duration estimate for each activity. 5. In 4—Precon Schedule, develop a preconstruction schedule by manually inputting the sequence of preconstruction activities (e.g., bar chart method). The preconstruction duration will be the longest path from the start of the first preconstruction activity to the end of the preconstruction schedule. Enter this duration and contract start date to obtain an estimated end date for the preconstruction period. Check whether the tentative schedule satisfies the milestones shown in Table 4-1 (Preconstruction Milestones) within the tool. Finalize the schedule after applying necessary adjustments. Tips • This tool requires Excel macros to be enabled. • This tool requires user input and is not fully automated. • The resulting duration (or date) should not be assumed to be definitive. Users must apply professional judgment before selecting the contract time.

A-32 Systematic Approach for Determining Construction Contract Time: A Guidebook CHAPTER 5. RELATIONSHIP OF CONTRACT TIME TO RISK MANAGEMENT T5.1: Risk Breakdown Structure What Is It? Risk breakdown structure (RBS) is a simple tool for identifying and categorizing risks through a hierarchical structure. It is a multilevel breakdown table that shows potential risk source and category. Risk factors are taxonomized consistently. The RBS can assist in understanding the distribution of risk on a project. When to Use It? RBS is a helpful tool for risk identification, which is generally conducted at the early stages of project development. Because risk identification is a continuous effort, RBS should be used and updated at major milestones in project development process. RBS can also be used at the post-construction review phase to identify repeatedly occurring risks across projects. Why Use It? RBS can help determine whether the risk identification method has covered all potential sources of risk (Hillson 2003). Based on RBS, the DOT can develop a consistent taxonomy and code for each risk factor (WSDOT 2014). The developed code is used as an input to better organize and track specific risk items in the risk register. The result of risk identification methods tends to be an unstructured list of risks that does not indicate the focus of risk management attention. With RBS, identified risk items can be categorized by their source, and the most significant sources of risk to a specific project stand out. The project manager can also monitor and track risks in a consistent and convenient way. At the post-project review phase, RBS can help to identify the recurring risk themes or concentration of risk, which also helps the development of a risk database by category. How to Use It? The upper levels of the RBS are the risk sources, and they are used as a prompt list to ensure coverage during risk identification (Level 1 in Figure A-3). After risk identification, risk items can be categorized by allocating and mapping them to the lowest levels of the RBS (Level 2 in Figure A-3). The code for each item in the risk register (RBS ID in Figure A-4) can be assigned based on the categorization. The risk manager can identify areas of concentration of risk by simply counting the items under different risk sources and can allocate the management effort accordingly. It should be noted that the RBS can be adjusted and expanded based on each DOT’s experience with projects.

Tools A-33   Figure A-3. Exemplary risk breakdown structure. Figure A-4. RBS ID in risk register.

A-34 Systematic Approach for Determining Construction Contract Time: A Guidebook Example An Excel template was developed for reference. The categorization in the exemplary Excel sheet is not a standard one because each DOT may have its own way of classification. The Excel sheet can be easily modified to serve the DOT’s own purpose. References Hillson, D. (2003). “Using a risk breakdown structure in project management.” Journal of Facilities Management, 2(1), 85–97. WSDOT (2014). Project Risk Management Guide. Engineering and Regional Operations, WSDOT.

Tools A-35   T5.2: Risk Mitigation Plan What Is It? A risk mitigation plan (RMP) is a template that structures and organizes the risk responses and monitor measures. It generally documents the risk response and control actions. RMP can be directly expanded from the risk register. When to Use It? For smaller projects, RMP can be developed after the qualitative schedule risk assessment and before the completion of the final design. For larger projects, a risk mitigation workshop can be convened to establish the RMP after the full-fledged probabilistic risk assessment (quantitative). During the bid proposal development phase, the risk mitigation strategies should be considered and incorporated when designing and drafting the contract. RMP is also a guideline for monitoring previously identified risk factors and managing schedule contingency at the project construction stage. Why Use It? RMP is a guideline for the project team to reduce and minimize the impacts of identified risks. With RMP, the response strategy and specific action to be implemented are clear, and an effective tool to document the response strategy and specific action to be implemented can be developed and adjusted during the project lifecycle. How to Use It? Risk mitigation can incorporate Pareto’s Principle, also known as the 80/20 Rule, which states that for many events, 80 percent of effects is due to 20 percent of the causes. Therefore, the RMP should focus on the top risks. Project teams can start working with the prioritized list of the identified risks outputted from risk analysis. Generally, five risk mitigation strategies exist: (1) avoid; (2) accept; (3) share; (4) transfer; (5) reduce. Specific actions for each risk item should be designed to implement the strategy. Risks are usually allocated to the party that is capable of dealing with it effectively. For example, technical risks can be owned by the project team, while non-technical risks might be more properly left to a DOT’s executive management and policy boards. Project risks change as the project matures. Regular project risk review is suggested to ensure that response actions are followed through. Example Figure A-5 shows an Excel template developed by expanding the risk register for reference.

A-36 Systematic Approach for Determining Construction Contract Time: A Guidebook Figure A-5. Risk register and mitigation plan template.

Tools A-37   CHAPTER 6. POST-CONSTRUCTION CONTRACT TIME EVALUATION AND FEEDBACK LOOP T6.1: Post-Construction Contract Time Performance Evaluation Checklist What Is It? Most state DOTs conduct post-construction review (PCR) meetings, though the level of implementation differs. In addition, contract time evaluation typically constitutes only a small portion of a PCR meeting. Although PCR meetings are generally well documented in most DOTs, it is unclear how lessons learned (LLs) from completed projects are fed back into the decision-making process of future projects. If contract time developers do not revisit and reassess the validity of the various assumptions that they made to establish contract time for letting, they may keep making similar assumptions on future projects without clearly understanding the applicability and limitations of these assumptions. Thus, valuable learning opportunities are lost, and the problem of possibly inaccurate contract time perpetuates because the root cause is not identified. Without a formal guide on conducting contract time performance evaluation, it is unlikely that state DOTs will observe any significant improvement in the accuracy of their CTD. In an attempt to address these problems, this tool serves as an agenda for DOTs to perform contract time evaluation during PCR meetings and as a tool to facilitate the learning process within DOTs. When to Use It? This tool can be used during a project performance evaluation meeting (e.g., PCR meeting). Why Use It? Most DOTs do not have a formal approach to evaluating contract time performance after project completion. With potentially so many issues to be discussed during a post-construction meeting, attendees may not have sufficient time to discuss contract time evaluation. Even if a state DOT does evaluate its contract time performance on a project, the assessment will most likely be a very brief discussion. This tool is developed to guide DOTs in conducting a more comprehensive review regarding contract time of a project while at the same time encouraging DOTs to complete the feedback loop, which is the first step in enabling organizational learning within the agency.

A-38 Systematic Approach for Determining Construction Contract Time: A Guidebook What Does It Do? This checklist aims to help DOTs assess their performance in determining and executing the contract time of a project. It encourages a holistic reflection by asking PCR participants to evaluate the actual project schedule from multiple perspectives and to identify the real impact of influential factors on contract time. This tool also intends to capture, in an organized manner, any LLs/experience that may potentially benefit other projects in the future. How to Use It? Answer each question carefully. Gather as much input as possible from project team members. Tips • For longer projects, consider having an interim meeting to evaluate the ongoing project performance to minimize the possibility of essential LLs or knowledge being forgotten by waiting until the end of the project. Use this tool as a guide for the meeting and answer those questions based on the performance data at hand. When the times comes for the post-construction review, update/add responses as necessary. • For better results, consider using a facilitator to lead the discussion and another person to record the responses. • Ensure that these documented LLs/knowledge are somehow disseminated to the entire agency (refer to Chapter 6 for more information).

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Contract time affects the cost of construction, traffic disruption and public inconvenience, the economic impact of projects to the surrounding areas, and schedule risks.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 979: Systematic Approach for Determining Construction Contract Time: A Guidebook provides state departments of transportation guidance for producing consistently credible, reliable, and defensible contract time estimates.

Supplemental to the report is NCHRP Web-Only Document 298: Developing a Systematic Approach for Determining Construction Contract Time, a spreadsheet-based Toolkit, a Technical Memorandum, and a Presentation.

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