National Academies Press: OpenBook

Risk-Based Construction Inspection: A Guide (2023)

Chapter: Chapter 4 - Determine Project-Level Resource Optimization

« Previous: Chapter 3 - Risk Assessment to Determine Priority of Inspections and Acceptance Methods
Page 27
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 27
Page 28
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 28
Page 29
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 29
Page 30
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 30
Page 31
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 31
Page 32
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 32
Page 33
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 33
Page 34
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 34
Page 35
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 35
Page 36
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 36
Page 37
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 37
Page 38
Suggested Citation:"Chapter 4 - Determine Project-Level Resource Optimization." National Research Council. 2023. Risk-Based Construction Inspection: A Guide. Washington, DC: The National Academies Press. doi: 10.17226/27099.
×
Page 38

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

27   A prioritized list of risk-based inspection strategies is developed in Stage 3: Risk-Based Inspec- tion Strategies. This chapter will focus on Stage 3, particularly on the optimization of project- level inspection resources. In Stage 3, the construction project team or project manager should determine the optimal levels of inspection and testing resources based on the risk scores for the constructed item or material and project. As part of this determination, consider specific project characteristics and factors that affect the required level of construction inspections for a given project. Factors include the general project profile (risk profile), the experience level and workload of the avail- able in-house and outsourced inspection staff, industry experience and capabilities, advanced technology applications, and alternative project delivery methods that could reduce the required level of inspection resources needed for a specific project. Figure 4.1 displays an overview of project-level resource optimization in Stage 3. 4.1 Step 1. Quantify Inspection Resources Based on Risk Tier The construction inspection and material tiers established in Stage 2 are the basis for estimat- ing the inspection resources needed for a particular item. The higher the risk (likelihood and impact) of failure for a given work item, the greater the levels of inspection and testing resources needed. Standard or more frequent inspection and sampling and testing would be necessary for higher-risk items, whereas materials certification or intermittent inspection would be sufficient for lower-risk items. Inspection resources can therefore be optimized by applying a risk-based approach that reduces inspection and testing frequencies for lower-risk items. The risk tiers established in Stage 2 to assign different levels of inspection (full-time—continu- ous, part-time—intermittent, or end-product—after completion) are used to quantify inspec- tion resources. The risk tiers and inspection frequencies are then equated to an approximation of inspection hours per working day as shown in Table 4.1. A preliminary project schedule can be utilized to estimate projected inspection hours for construction operations and activities by phase or type of work. The total number of inspection hours can then be estimated for each phase as set out in a hypothetical pavement rehabilitation project example shown in Table 4.2. The pavement rehabilitation project is segmented into phases of construction operations with corresponding inspection activities and durations for each major phase of work. Inspection activity frequencies are then assessed for each work item based on the risk tier for the work activity. This expected inspection frequency is translated to the average inspector hours per workday for each inspection activity. Inspector hours per work- day multiplied by the activity duration equals the inspector hours needed for the major project phases of work. C H A P T E R 4 Determine Project-Level Resource Optimization

28 Risk-Based Construction Inspection: A Guide Project Profiles Required Inspection Staff Available Inspection Staff Staff and Workload Inspection Technology Alternative Delivery Inspection Frequency Inspection Documentation Stage 3: Risk-Based Inspection Strategies Prioritized Construction Inspections Guidance & Risk Mitigation Strategies No. Construction Operation Inspection Activity Tier Risk Impact Inspection Frequency Inspector Experience Inspection Doc. e-inspection Availability 1 Earthwork Provided Provided Provided Provided Select Select 2 … … … … … … … * … … … … … … … … Inputs from Project Team Figure 4.1. Overview of project-level resource optimization in Stage 3. Risk Tier Construction Activity Description Inspection Frequency Hours/ Working Day High Construction activities or operations that require inspection during most of the time that work is ongoing and includes work that is buried or contains safety components Full-time (F/T) continuous inspection presence during the entire operation Standard material testing frequency 7–10 Moderate Construction activities that require inspection at critical times or hold points and intermittent monitoring for compliance and quantity measurements Part-time (P/T) intermittent inspection at critical times in the operation Reduced frequency of testing combined with certification 4–6 Low Items that can be accepted through end-product inspection or certification. These items of work should be inspected during the construction operation randomly during other inspection downtimes End-product (E/P) inspection after the construction item is complete or installed Random/programmatic testing and certification 1–3 Table 4.1. Example of assigning inspection resources.

Determine Project-Level Resource Optimization 29   For this example, a pavement rehabilitation project with an approximate 6-month duration, the total estimated inspection hours amount to 1,630 hours for approximately 125 workdays. This translates to approximately 1.63 FTEs (full-time equivalent) for risk-adjusted construction inspection resources. NCHRP Research Report 923: Workforce Optimization Workbook for Transportation Con- struction Projects (Taylor et al., 2020) provides a useful statistical summary of average FTE inspector data compiled from a national database of more than 300 highway projects as shown in Table 4.3. The data indicate that an inspection crew may range from approximately 2 to 4 FTEs depend- ing on the project type (operation). This was consistent with DOT feedback indicating that a mix of 2 to 3 inspection staff is typically assigned for average-size projects with normal production. This average FTE mix of staff can be further refined or mitigated based on project profile (size and complexity), inspector experience levels, technology, and other factors. 4.2 Step 2. Adjust Project Inspection Resources Based on Risk Mitigation Strategies 4.2.1 Project Profile Considerations The inspection levels and core construction items can potentially be further reduced based on project profiles. The profiles have been defined as follows based on standard DOT project Phase of Work Inspection Activity Description Duration (WDs) Inspection Frequency Hours/ WD Inspector Hours Earthwork/ Embankment Excavation and Backfill Placement 50 F/T 8 400 Geotextile Placement 5 E/P 2 10 Subbase/Base Course Verify Lift Thickness 45 P/T 4 180 Compaction Control Placement Inspection 45 F/T 8 360 Flexible Pavement Placement Thickness and Grade 30 F/T 8 240 Finish texture/Surface Smoothness 30 E/P 2 60 Miscellaneous Temp. Traffic Control 125 P/T 3 375 Pavement Marking 5 E/P 1 5 Total 1,630 Note: WD = workday, F/T = full time, E/P = end product, P/T = part time. Table 4.2. Hypothetical pavement rehabilitation project example: assigning inspection resources.

30 Risk-Based Construction Inspection: A Guide characteristics ranging from high-profile (large, complex, high-cost) projects to low-profile (small, noncomplex, low-cost) projects. • High-Profile or High-Cost. New interchanges, large material quantities, complex (major) urban roadway or bridge construction, major reconstruction, adding or widening (new con- struction, reconstruction [4R] or resurfacing, restoration, rehabilitation [3R] with multiphase traffic control), and high ESALs (equivalent single axle load). • Medium-Profile or Medium-Cost. Average material quantities, moderately complex bridge replacements with minor roadway approach work, minor roadway relocations, and medium ESALs. • Low-Profile or Low-Cost. Small quantities, culvert reconstruction, rural overlay or re-decking, noncomplex enhancement projects without new bridges (e.g., bike trails), overlay projects, simple widening without right-of-way take (or minimum right-of-way take), little or no utility coordination; and simple 3R projects; low ESALs. For high-profile projects, failure or rework would presumably result in a more severe con- sequence; therefore, the inspection and documentation should be at least the standard level of inspection and testing. NCHRP Research Report 923 (Taylor et al., 2020) included an adjustment factor of 0.94 for standard FTE inspection resources for medium-profile projects and 0.77 for low-profile projects. Therefore, a less complex, lower-profile project would reasonably require fewer resources, less documentation, and reduced sampling and testing or acceptance by cer- tification. Assuming the example project in Step 1 is a medium-profile project, the inspection resource of 1.6 FTE could be further reduced to 1.5 FTE [1.6 x 0.94 = 1.5]. An added consideration is that high-profile and complex high-risk projects (e.g., major bridge replacements or rehabilitations) may not necessarily require more or full-time inspection, par- ticularly if the pace or intensity of the construction is not commensurately high. The focus would be to adjust the mix of staff by assigning more experienced inspection staff. Similarly, a low- or medium-profile project performed under accelerated production (extended shifts with con- tinual inspection frequency) would require more inspection resources. Therefore, the project characteristics and required production rates need to be carefully considered when assigning or adjusting inspection resources. 4.2.2 Inspector Experience The project may require a mix of inspection staff for specific items of work (i.e., earthwork, asphalt paving, concrete structures) based on a typical inspection workload for the project or Project Type Senior Inspector Intermediate Inspector Junior Inspector Road—New Construction/Expansion 1.69 1.95 0.63 Road—Rehabilitation/Resurfacing 0.9 1.01 0.71 Bridge—New and Replacement 1.17 0.92 0.5 Bridge—Rehabilitation 0.81 0.92 0.23 Other Projects 0.68 0.66 0.32 Special Structures (Rest Areas, Weigh Stations) 0.67 1.67 0.33 All 0.93 1.01 0.51 Table 4.3. Average FTE inspection for project types (adapted from Taylor et al., 2020).

Determine Project-Level Resource Optimization 31   material type. A high-profile, high-cost project will typically require a greater number of full- time inspection staff with appropriate experience levels. A lower-profile project might justify fewer and less seasoned inspection forces with the caveat that the intensity of production may dictate the level of inspection regardless of the project profile. If the required level of the inspection exceeds what is available in-house, the DOT needs to determine whether outsourcing is needed to fill the gap. The DOT can assess whether the in-house inspection workload can be optimized by prioritizing inspections, using more expe- rienced inspection staff, and reducing inspection levels and frequencies for lower-risk work items requiring less inspection and documentation. This study included three levels of inspector experience (e.g., a junior inspector with less than 2 years of experience, an intermediate inspec- tor with 2–5 years of experience, and a senior inspector with more than 5 years of experience). An example determination of the optimal level of inspector experience for selected work-type inspection activities is shown in Table 4.4. Appendix A includes example input forms for com- bined inspection frequency, documentation effort, and inspector experience levels. TYPICAL WORK TYPES Inspector Experience 1 Lift Thickness: Verify material placement within specified lift thickness. < 2 years 2 Embankment Stability: Ensure stability of embankment and slope against sliding by providing suitable materials, construction, foundation and a suitable bond. 2 to 5 years 3 Embankment Fine Grade Line: Ensure embankment to be constructed according to plan limits, and finished to specified line and grade. < 2 years ….... Erosion Control: Verify installation and maintenance of temporary erosion control devices and compliance with permits and Contract requirements. 2 to 5 years … Others:_______________________________ 1 Compaction Control: Verify moisture content, watering operations, and compaction. 2 to 5 years 2 Placement Inspection: Inspect placement of base course material and review checklist including required construction operations and tests. < 2 years ….... Surface Smoothness/Tolerance: Inspect and document finished grade for smoothness and line and grade, and determine if all loose and segregated areas are repaired. < 2 years … Others:_______________________________ 1 Expansion Joint Inspection: Verify construction of expansion joints according to plans and specifications. 2 to 5 years 3 Assembly, Erection, and Testing of Steel Girder Elements: Verify assembly, erection, and testing of steel girder elements according to contract plans and specifications. < 2 years 4 Precast Concrete Deck and Girders Placement: Inspect placement of precast concrete deck panels and girders; check for any damage or cracks. < 2 years ….... Monitoring Concrete Placement Duration: Verify concrete placement within specified duration to avoid hardening. 2 to 5 years … Others:_______________________________ Earthwork and Embankment (including structural backfills) Subbase/Base Course Bridge Deck and Girder CORE INSPECTION ACTIVITY Table 4.4. Determination of optimal inspection experience levels for work types.

32 Risk-Based Construction Inspection: A Guide Once the appropriate inspector experience levels for work item inspection activities are defined, a DOT can refine its inspection resource allocation estimated in Step 1 to achieve the optimal inspection crew mix. NCHRP Research Report 923 (Taylor et al., 2020) includes a pro- grammatic staff allocation module that can be used to determine whether the available FTE inspection staffing levels are sufficient to meet the required staffing levels and mix for a project (or program). This approach can be used in a similar way to determine whether there are gaps in staffing for a project that would need to be filled through outsourcing or if the gap could be closed using additional workload reduction strategies. 4.2.3 Industry Capabilities As more responsibilities are shifted to the industry, the DOT needs to, at a minimum, verify that the industry has the requisite experience and qualifications to perform the construction work with appropriate inspection and testing controls. This verification may include a review of past performance, certifications to perform types of work, quality management capabilities, or other qualifications. A DOT can then decide to adjust its mix of DOT inspection and docu- mentation levels based on the assessment of industry capabilities. DOTs in some regions (e.g., Mid-Atlantic or Southeast) that use the same industry suppliers have pooled their resources to share in the plant inspection and documentation responsibilities. A representative risk management PI matrix (Figure 4.2) has been used by the Caltrans Office of Structural Materials (OSM) for the acceptance of fabricated materials and items to determine Figure 4.2. Risk-based matrix tool for materials (Caltrans, 2022).

Determine Project-Level Resource Optimization 33   the required levels of DOT plant inspection. The levels of inspection (i.e., programmatic, inter- mittent, continuous) are tied to how consistently the plant has produced quality materials and products among other risk considerations. 4.2.4 Emerging Technology and Construction Methods Various e-Construction and advanced technologies have been demonstrated to improve construction inspection efficiency and reduce inspection resource levels and documentation effort. These technologies are helping to fill the gap between an increasing number of high- way construction projects and declining and less experienced inspection resources. Table 4.5 summarizes the maturity levels of inspection and documentation practices ranging from tradi- tional visual inspection and paper-based documentation to evolving e-inspection processes and advanced technology applications currently being implemented. DOTs are rapidly implementing electronic 3D modeling systems that include a listing of elements requiring construction inspection. The system utilizes checklists with a database of pictures and video content that field inspectors use to assess the quality of work and materials and enter data into the system. The 3D model further addresses pay items and assessment of quantities to document payment. The FHWA has promoted the use of automated machine guid- ance (AMG) and estimated that using data from technologies such as 3D modeling in combina- tion with GPS, AMG can increase productivity by up to 50% on some operations and cut survey costs by as much as 75%. Project-level optimization of construction inspection occurs when all elements built into and associated with the roadway are fully designed into the 3D model. Similarly, FHWA’s Everyday Counts program promotes the use of e-ticketing to enhance safety, quality, and cost savings as follows (FHWA EDC 6, 2022). • Safety. e-Ticketing enhances data collection and reduces exposure to adjacent vehicular traffic and construction equipment for inspectors and work crews while retrieving paper tickets. • Time Savings. Real-time access, via electronic handling of tickets, reduces processing time for quality assurance and payment, decreasing the inherent delays in paper-based project administration. • Quality. Project documentation is more consistent and efficient using e-ticketing platforms. Standardized data enable archiving for future reference, leading to improved design, con- struction, maintenance, and operations. Potential inspection staffing reductions or efficiencies can be realized using evolving tech- nologies and e-inspection practices. The e-Construction implementation has not, in all cases, resulted in improved productivity for all inspection-related activities, however. New e-tools for field data collection (e.g., photographic and video content using unmanned aerial systems Maturity Level Description Low Visual inspection and paper-based documentation. Intermediate Paper and e-processes. Advanced E-processes (e.g., e-bidding, e-ticketing, mobile field devices/e-books, geospatial 3D Models, global navigation satellite system [GNSS]). Photographic and other media observations. E-data collection/access in the field. Remote sensing, video monitoring, intelligent compaction, automated machine guidance (AMG), digital terrain models (DTM), UASs, robotics. Table 4.5. Maturity level of construction inspection and documentation.

34 Risk-Based Construction Inspection: A Guide [UASs] or remote sensing or video monitoring technology) have created data storage and pro- cessing issues. In general, the trend toward the use of e-tools to collect data and manage construc- tion will continue but may be somewhat constrained by accessibility to wi-fi networks and the effective processing of information and data. DOTs must carefully consider how emerging tech- nology can optimize inspection resources and reduce the inspector documentation level of effort. A compendium of emerging e-Construction and emerging technology applications is included in Appendix C of this guide. The compendium briefly describes the technology; what it can do in the context of optimizing inspection; why, when, and how to use it; and a list of additional resources. Because this area is still relatively new to many state DOTs, it will be the focus of an upcoming TRB project. NCHRP Project 10-110, “3D Modeling Guide for Construction Inspection” will deliver a 3D modeling guide for construction inspection. 4.2.5 Documentation Level of Effort While the primary role of inspection is to verify and document quality (i.e., the extent to which the work complies with plans and specifications), DOT practitioners agree that a significant percentage of total inspection time is spent on calculation and documentation of quantities for pay estimates, recordkeeping, offsite activities (meetings, training), environmental compliance, traffic management, contract closeout, and other administrative compliance and documenta- tion duties. In some cases, documentation efforts could occupy up to 50% of an inspector’s time. Optimizing documentation is considered essential to managing time with scarce resources and allowing more time for actual quality inspection. A similar risk-based approach can be used to prioritize and, where possible, reduce the documentation required for construction activities for lower-risk items and to explore the use of technology. One example of a suggested approach to free up more time for core inspection would be to expand the use of plan quantities for pay estimates to reduce the time needed for detailed field measurements and documentation. Another DOT consensus finding was that e-ticketing was a big inspection time and cost-saver for hot mix asphalt (HMA). Alabama DOT (ADOT) con- ducted more than nine projects piloting e-ticketing through 2020 and found that the elimina- tion of the “ticket taker,” or junior inspector for a paving resurfacing operation, can result in improved safety and significant cost savings for the typical pavement rehabilitation program. ADOT estimated that the potential cost savings in Construction Engineering and Inspection (CE&I) by using e-ticketing for ADOT’s annual resurfacing program could amount to $4–8 million that can be reinvested in future projects (ADOT, 2020). GPS and cellular data are also being used for materials tracking (i.e., material haulers) in conjunction with e-ticketing and fleet management. These new e-tools for field data collection (e.g., photographic and video content) also create electronic data storage and processing issues. In general, the trend toward the use of e-tools to collect and manage data will continue but be tempered by accessibility to wi-fi networks and effective processing software and data. An evaluation of the documentation level of effort should consider the time spent document- ing quality-related inspections, payment, and other contract administration duties. These may include quantity calculations and recordkeeping for other contract compliance requirements (e.g., Americans with Disabilities Act, Storm Water Pollution Prevention, labor compliance). A sim- plified rating system can be used, as shown in Table 4.6, for an implementing DOT to assess the required documentation level of effort. An example input sheet shown in Table 4.7 illustrates assigned ratings for documentation efforts. The ratings can be used to prioritize or reduce documentation levels based on the core

Determine Project-Level Resource Optimization 35   Tier/Level Short Description Level of Effort (% of inspector time) Long Description 3/High Daily per segment or operation 30–50 Documentation is typically required daily during active work specific to the item. 2/Moderate Intermittent per segment or operation 10–30 Documentation frequency is required at major intervals or hold points in the construction process of the item (e.g., prior to being covered by subsequent work). 1/Low Once per operation or project <10 Documentation is required once per operation or per project for all similar items (e.g., all shrubs, all traffic devices). Table 4.6. Construction documentation level of effort. TYPICAL WORK TYPES Documentation Effort 1 Lift Thickness: Verify material placement within specified lift thickness. Moderate 2 Embankment Stability: Ensure stability of embankment and slope against sliding by providing suitable materials, construction, foundation and a suitable bond. Minimum 3 Embankment Fine Grade Line: Ensure embankment to be constructed according to plan limits, and finished to specified line and grade. Minimum ….... Erosion Control: Verify installation and maintenance of temporary erosion control devices and compliance with permits and Contract requirements. Moderate … Others:_______________________________ 1 Compaction Control: Verify moisture content, watering operations, and compaction. High 2 Placement Inspection: Inspect placement of base course material and review checklist including required construction operations and tests. Minimum ….... Surface Smoothness/Tolerance: Inspect and document finished grade for smoothness and line and grade, and determine if all loose and segregated areas are repaired. Minimum … Others:_______________________________ 1 Expansion Joint Inspection: Verify construction of expansion joints according to plans and specifications. Very High 3 Assembly, Erection, and Testing of Steel Girder Elements: Verify assembly, erection, and testing of steel girder elements according to contract plans and specifications. High 4 Precast Concrete Deck and Girders Placement: Inspect placement of precast concrete deck panels and girders; check for any damage or cracks. Moderate ….... Monitoring Concrete Placement Duration: Verify concrete placement within specified duration to avoid hardening. High … Others:_______________________________ Earthwork and Embankment (including structural backfills) Subbase/Base Course Bridge Deck and Girder CORE INSPECTION ACTIVITY Table 4.7. Example risk-based assessment of documentation level of effort.

36 Risk-Based Construction Inspection: A Guide inspection activity. Assuming that a “high” rating would equate to the standard or default docu- mentation levels, the implementing DOT would need to decide to what extent documentation effort can be simplified or reduced for specific work types, or whether or not other acceptance methods or technology tools (i.e., acceptance by plan quantities, e-ticketing, e-field books, remote monitoring, 3-D modeling) can reduce the inspector data entry time and documenta- tion levels of effort for acceptance. Appendix A includes an example input form for combined inspection frequency, documentation effort, and inspector experience levels. 4.2.6 Alternative Delivery While there is no discernible change in the level of inspection for quality between tradi- tional design-bid-build (D-B-B) and design-build (D-B) projects, the inspection responsibility is shifted to the contractor inspection forces, which may effectively reduce the level of DOT inspection and testing. When DOTs use contractor QC inspection and testing in the acceptance decision for a project, DOT QA verification testing is done at a reduced frequency (i.e., 10–25% of the standard frequency) using alternative delivery. This approach can potentially reduce the overall number of tests per lot or volume of materials for operations that are statistically under control (unless the contractor decides to increase its QC testing). Similarly, the use of a perfor- mance warranty or post-construction maintenance provision shifts greater responsibility for quality management to the contractor, which will often reduce the level of DOT inspection and testing. An additional time-saving advantage for a project using alternative delivery methods, par- ticularly for design-build, is the use of lump-sum pay items that eliminate detailed field quantity takeoffs by DOT inspectors for payment purposes. The DOT inspection staff still might track quantities for quality testing and verify the percentage-complete estimates of an item for pay- ment purposes, but they do not perform detailed field measurements for quantity takeoffs. 4.3 Summary of Strategies to Optimize Inspection Resources To summarize strategies for optimizing or reducing inspection and documentation levels, and materials testing and acceptance methods, Table 4.8 below summarizes project-related fac- tors and considerations that can influence the inspection strategy and resource requirements for a given project. Use these project-related factors and considerations to qualitatively determine whether DOT or external consultant inspection resources can be further optimized or adjusted.

Determine Project-Level Resource Optimization 37   Factor Considerations Possible Optimization Strategies Project Profile (criticality/complexity) Does the project have a low-risk profile based on size, location, or complexity? Is the work item in question located outside the traveled way? Is the item nonstructural? Is a normal production rate appropriate? For a low-risk project (e.g., low- volume rural roadway or culvert reconstruction), consider the following options. Acceptance based on end-product visual inspection. Acceptance based on certification backed by random or periodic tests. Inspection Staff Experience Does the operation or activity require more experienced inspection staff? What is the right crew mix for the specific operation or project? If there is a shortfall in required FTE inspection staff, can the gap be closed with the available inspection staff? Determine the optimal mix of inspection staff (entry-level, intermediate-level, senior-level) for specific activities or projects based on inspection priorities. Reduce inspection staff based on project profile, industry capabilities, technology use, and other factors. Contractor and Supplier Qualifications and Experience Does the contractor, fabricator, or supplier (as applicable) have a history of consistently acceptable performance (i.e., compliance with specifications or with national or regional quality standards, such as NTPEP)? Are the materials being provided from a preapproved source, QPL, or similar? Does the contractor/supplier have a Quality Management Plan? If the DOT has confidence in the reliability of the contractor or supplier, consider the following options. Reduce sampling and testing or inspection frequency. Consider programmatic, system- wide, or regional testing or certification. Accept by certification backed by the desktop audit of certification documentation and visual inspection. Material Criticality and Quantities Is the planned quantity less than the minimum required test lot? Has the material been previously approved or certified? Has the material been recently tested with satisfactory results? Is the material structurally significant? Has initial testing verified the material supply is relatively uniform or statistically under control? Reduce sampling and testing frequency. Accept based on visual inspection or certification. Eliminate selected in-process test properties (e.g., focus on end-result testing). Table 4.8. Factors influencing levels of inspection and materials acceptance. (continued on next page)

38 Risk-Based Construction Inspection: A Guide Technology Are e-applications (mobile field devices) being implemented for the collection of field inspection and testing data? What technology tools have the greatest immediate potential to save time and allow field inspectors to inspect and document more work with fewer resources? What technology tools should be implemented as a long-term strategy to enhance inspection and improve productivity or performance of constructed assets. What are the challenges or constraints to implementing technology tools? Short-term implementation strategies to save inspector documentation time include the following. e-ticketing mobile field devices video cameras automated machine guidance unmanned aerial systems Digital Terrain Modeling Long-term implementation strategies include the following. Geospatial 3D-4D Models ultrasonic testing intelligent compaction smart sensors Documentation Levels Consider whether documentation can be reduced in alignment with inspection priority or material criticality. Can technology tools (mobile field devices, e-ticketing) save time or improve efficiency through real-time e- data input and e-documentation? Can documentation for low-risk field operations be simplified or limited to end-of-operation or project? Use plan quantities for structural elements, concrete, low-risk, or small quantity pay items with contractor certifications of compliance. Create e-checklists that prioritize inspection elements and link to inspection documents. Implement e-ticketing as a standard practice. Shift responsibility for quantity measurements to industry. Use mobile field devices that can import data into a database in one step. Factor Considerations Possible Optimization Strategies Project Delivery Methods Is the project being delivered using an alternative delivery method (e.g., design-build) that places more responsibility for payment verification and performance on the industry? Is the contractor required to submit and implement a detailed, project-specific Quality Management Plan? Will the material be covered under a warranty or post-construction maintenance provision? Use contractor QC test data in acceptance decision with independently validated test data by the DOT or its agent at an optimal testing frequency. Use contractor detailed quantity calculations with DOT verification of lump-sum items. Use more performance-oriented or end-result tests. Table 4.8. (Continued).

Next: Chapter 5 - Implementation Strategies »
Risk-Based Construction Inspection: A Guide Get This Book
×
 Risk-Based Construction Inspection: A Guide
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF

Due to budget cuts and reduced experience levels of inspectors and engineers, state departments of transportation (DOTs) have implemented risk-based strategies to achieve greater efficiency in construction inspection. These strategies include prioritizing inspection based on inherent risks related to construction operations, using emerging technology applications to save time, and accepting certification and contractors' test results to offset shortages of experienced inspection resources.

NCHRP Research Report 1039: Risk-Based Construction Inspection: A Guide, from TRB's National Cooperative Highway Research Program, discusses the importance of construction inspection and aims to assist state DOTs and the U.S. Federal Highway Administration in meeting quality standards.

Supplemental to the report are NCHRP Web-Only Document 344: Risk-Based Construction Inspection: Conduct of Research Report and an Inspection Risk Assessment Questionnaire.

READ FREE ONLINE

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  6. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  7. ×

    View our suggested citation for this chapter.

    « Back Next »
  8. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!