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6 Literature Review This review focuses on previously published academic literature on several ADC project- delivery technologies. The technologies being reviewed are 3-D models, small UAS, electronic bidding, e-Ticketing, electronic construction document management systems and digital signa- tures, construction administration software, mobile devices for inspection, reality capture, IC, 5G/small cell technology, AMG, and AR. Some documented knowledge exists for these tech- nologies, especially related to their use in the highway-construction industry. Based on available literature, the discussion may not perfectly map the ADC technologies that are identified and surveyed in this synthesis. The review begins with a brief overview, potential uses, and applications in the transportation-construction industry. The review then describes some of the potential benefits resulting from the implementation of the technology, and it ends with providing some of the challenges and potential drawbacks that can be a barrier for implementation or success. 2.1 3-D Models 3-D modeling in transportation construction is a mature technology that is the cornerstone of the modern digital jobsite. With the benefit of 3-D modeling more widely recognized, the US highway industry will likely transition from traditional 2-D modeling to 3-D modeling (FHWA 2017a). Recent evidence indicates that the adoption of 3-D modeling and BIM has been increasing (Bradley et al. 2016). The shift from 2-D plans to 3-D modeling was primarily driven by contractors using AMG, and the process of reengineering 2-D plans was burdensome and time consuming (Dadi et al. 2021). 3-D modeling has many applications and uses in trans- portation infrastructure. Those include risk management, safety control, and integration with other technologies, such as unmanned systems and robotics; sensing technologies and sensors; cloud computing and mobile services; laser scanning and photogrammetry; virtual design and construction; augmented and virtual reality (VR); GPS; geographic information systems (GIS); and life cycle analysis from the planning and design stages to the maintenance, structural moni- toring, and renovation stages (Costin et al. 2018). 3-D models are used as contract documents for the bidding process. As-built digital 3-D models are used for the purposes of maintenance and operations in the postconstruction phase of the project (Jung et al. 2014). 3-D modeling has many versatile benefits, such as cost and time savings and increased pro- ductivity (Torres et al. 2018). 3-D modeling allows for faster, more accurate, and more efficient planning and construction. 3-D modeling software allows the design and construction teams to connect virtually, which enables them to develop, test, and make changes to the project throughout the design and construction stages. It allows intricate and detailed design features to be viewed geospatially (i.e., 3-D view) from multiple perspectives, which can greatly help in the interpretation of design plans (FHWA 2017a). In a study by Guo et al., where extensive data was collected and 7 transportation agency site visits were made, it was found that 3-D modeling has C H A P T E R 2
Literature Review 7  benefits in better communication and visualization, improved productivity, reduced cost, less rework, 3-D design verification, error detection, and greater clarity in the design intent (2017). When 3-D models are used for contract documents, it can greatly facilitate the bidding process. As-built 3-D digital models have great potential for enhancing maintenance and operation efficiency, as well as proposed retrofitting operations (Woo et al. 2010; Jung et al. 2014). However, 3-D modeling does come with a number of challenges. Technical challenges include the lack of interoperability and information sharing across different software; insufficient knowledge; the need for hardware that can handle the processing of large volumes of data; and lack of definitions of data requirements as related to identifying to whom and when the data should be shared for the duration of the project (Costin et al. 2018). Legal challenges include the lack of consensus on legal clauses about the use of digital signatures, stamps, and deliverables; data integrity during transmission; confidential information; and difficulties of updating insur- ance policies to cover the responsibility of stakeholders (Costin et al. 2018). Additional challenges include the lack of standards, methods, and contractual language, particularly when used for contract documents in the bidding process; institutional resistance to change and adopting new technologies; and finally, lack of sufficient funding to make the large initial investment that includes updating software, hardware, information technology (IT) systems, training workers and engineers, and changing the project-delivery method (Costin et al. 2018). Also, as-built digital 3-D models are hard to create and require sophisticated equipment, and several attempts have been found to produce inaccurate models (Woo et al. 2010; Jung et al. 2014). 2.2 Small Unmanned Aircraft Systems Small UAS, also known as drones, are aircrafts without pilots on board, which are either operated by a human operator on the ground or autonomously using attached microprocessors (Liu et al. 2014). The majority of UAS used in construction are equipped with a camera; in relatively minor cases, LiDAR; a radio frequency identification (RFID) reader; or other types of sensors or technologies (Zhou and Gheisari 2018). Small UAS have seen a lot of development and applications in the construction industry. They have wide applications for construction in general, as well as transportation construction. Those include highway inspection, which use the collected small UAS data to evaluate the highway condition; damage assessment, to evaluate damages particularly after disasters; site surveying and mapping, which refers to the collection of spatiotemporal phenomena (i.e., capturing location data at a given time); safety inspection, which involves regular assessment of safety conditions on construction jobsites based on defined safety criteria; and progress monitoring, which evaluates work in progress. Other applications include maintenance, material tracking, aerial photography, congestion mapping, and produc- tion of as-built models (Zhou and Gheisari 2018). Beyond their applications, small UAS have a lot of benefits, particularly when used for trans- portation construction. Small UAS have the benefit of lower overall costs, reducing project delays and shrinking the project schedule, improving the safety record, the capability of gener- ating high-resolution aerial imagery, and more accurate data collection (McGuire et al. 2016). Also, when it comes to highway inspections, traditional inspection methods are labor intensive and time consuming; small UAS, on the other hand, require fewer support staff and no heavy logistics, resulting in fewer traffic disruptions and fewer road accidents during inspections (Otero 2015; Mardanpour et al. 2019). Small UAS can also collect data from hard-to-access areas and improve the quality of damage detection, assessment, and restoration planning (Zhou and Gheisari 2018). While small UAS have many benefits, their use and applications have some challenges. For instance, the FAA and some state or local policies restrict the use of small UAS (Irizarry and
8 Technological Capabilities of Departments of Transportation for Digital Project Management and Delivery Costa 2016). Small UAS use would also have to be balanced from the perspective of flight time and battery life, payload and maneuverability, and wind and weather conditions. Using small UAS also requires a costly initial investment in the small UAS itself, the training of staff that will operate the small UAS, and higher insurance costs (Irizarry and Costa 2016). Finally, the postprocessing of small UAS imagery is time-consuming and requires a lot of computing power to render 2-D and 3-D collected data (Zhou and Gheisari 2018). 2.3 Electronic Bidding Electronic bidding is the paperless electronic exchange and transfer of bid data between owners and bidders, including construction and contract documents; 2-D, 3-D, or BIM models; plans; bill of quantities (BOQ); specifications and standards; schedules; and so forth. In this process, the owner electronically shares this information with contractors, who in turn can load all the files and data, and then enter their bids through a shared system. Electronic bidding is used as a substitute for the paper-based bidding process (Arslan et al. 2006). Most DOTs in the United States have been adopting electronic bidding instead of the traditional bidding process (Nesan 2011). Electronic bidding in construction has many advantages. The traditional bidding process, which involves the receiving, checking, copying and distribution of paper drawings, BOQ, and specifications, is a tedious, time-consuming, and costly process, even for small construction projects (Arslan et al. 2006). Electronic bidding can facilitate this process and can significantly save time and reduce costs (McAllister and McClave 2010). Electronic bidding can also elimi- nate potential errors through automatic system checks and verifications, as well as provide an exchange medium among bidders and owners. The easy access through systems to project data can increase the number of potential bidders. Moreover, standard electronic bidding formats make technical data and price comparisons of submitted bids easier (Arslan et al. 2006). However, electronic bidding does not come without its challenges. For instance, for this process to work, all parties and stakeholders, including contractors and subcontractors, must agree to use this process. There are also legal concerns related to the authentication and security of bid submissions. Software compatibility issues may also be a hindrance to using this process (McAllister & McClave, 2010). 2.4 e-Ticketing e-Ticketing is a paperless process for tracking, documenting, and archiving material tickets that are accessible in real time using an electronic device. âThe Big 3â that e-Ticketing is used for are hot-mix asphalt (HMA), Portland cement concrete (PCC), and aggregate. Other e-Tickets are used for structural steel, rebar, precast PCC, and so forth (FHWA 2020b). e-Tickets summarize material information, including batch properties, delivery times, tonnage, material tempera- tures, or signatures (Newcomer et al. 2019). e-Ticketing is also used for inspection purposes and can be coupled with GPS and GIS to support real-time tracking of materials (Sturgill et al. 2019). The benefits for e-Ticketing are numerous. Traditional material paper ticketing practices are inefficient, require manual data entry, can cause delays in invoicing and payments, and can potentially endanger inspectors and workers (Sturgill et al. 2019). e-Ticketing can solve all of these problems by simplifying ticket handling, facilitating data integration into construction- management systems, and improving worker safety (FHWA 2020b). Other benefits include increased productivity, time efficiency, better time management, reduced manpower, cost- effective tracking, fast billing, reduced risk of losing tickets, simplified data collection, clean and readable information, improved transparency, and improved access (Nipa et al. 2019).
Literature Review 9  However, e-Ticketing implementation has been slow and challenging for DOTs. There is a lot of reluctance and hesitation from contractors to make the change to e-Ticketing, mostly due to the lack of knowledge of systems. Moving from traditional material ticketing to e-Ticketing requires a major financial investment in the system itself and training workers and inspectors on these systems. In addition, state DOTs are conflicted about whether they should use an external commercial vendor or develop in-house software (Nipa et al. 2019; Sturgill et al. 2019). 2.5 Electronic Construction Document Management Systems and Digital Signatures Electronic construction document management systems are systems where documents are created and submitted electronically, through a shared platform where authorized users are able to view, download, or take other authorized actions (Sulankivi et al. 2002). For the purposes of the survey described in Chapter 3, electronic construction document management systems were described as those used to transmit and store bidding and letting documents; however, there are use cases beyond those applications, which are described in this review. More and more transportation departments are considering the implementation of electronic construction document management systems (Guo et al. 2017). These systems are used to electronically capture, store, share, and submit documents, including design drawings; cost estimates; sched- ules; BOQ; meeting minutes; 3-D models; computer-aided drafting (CAD) plans; spreadsheets; progress reports; inspection reports; as-built records; or any other construction documents generated during the project. These systems are also used to facilitate electronic bidding through allowing contractors easy access to all documents and information (Guo et al. 2017). Through the systems, all documents can be signed using a âdigital signature,â which is a way to verify the sign-off or approval of documents by authorized personnel (Guo et al. 2021). These systems have numerous benefits in transportation projects. Projects usually generate an exorbitant number of hard-copy documents throughout the life cycle that need to be stored or shared with multiple stakeholders, and obtaining the required signatures is time consuming and costly. The systems can facilitate all of these processes through a shared, easily accessible plat- form, where all documents can be easily retrieved, transferred, and digitally signed. Documents can be stored for an indefinite amount of time without the worry of losing them. The systems can reduce time spent on document management and shipping costs of hard copies. Sulankivi et al. conducted a case study in Finland and found that using the systems resulted in 29 saved workdays (2002). The systems can also provide a more efficient workflow, improved document security, and a single source of information, and can achieve document transparency, effective communication, and a more environmentally friendly document-storing process by abandoning paper documents (Guo et al. 2021). While benefits are plenty, so are the challenges. The systems require a major initial financial investment and a complete overhaul of current construction document- and data-management strategies. Changing the current process also requires training of staff, personnel, and stake- holders on the new systems (Ahmad et al. 2017). There also legal challenges. Current legal prac- tices mostly address traditional paper-based delivery of documents. But in these systems, issues related to data ownership, licensure, and liability of project models, plans, and as-built data may come into the spotlight. There are currently no standardized procedures that address digital models and data sharing as part of contract documents. Also, it is unclear whether electronic communication and document sharing in construction meet the evidentiary requirements to be admissible in court in case of disputes among the involved parties (Christensen et al. 2007; Guo et al. 2017).
10 Technological Capabilities of Departments of Transportation for Digital Project Management and Delivery 2.6 Construction Administration Software Construction administration software, like AASHTOWare Project software, are systems that manage a transportation agencyâs construction program. Over 40 state DOTs in the United States use construction administration software, specifically AASHTOWare Project, in some capacity. These software manage the entire construction contract life cycle by covering cost estimation, proposal preparation, bidding and bid analysis, construction management and inspection, material management, civil rights, labor management, and data analytics to make effective decision-making (AASHTOWare Project 2021). Using construction administration software, like AASHTOWare Project, has many potential benefits. Because such software manages so much data relating to all phases and aspects of con- struction projects, the software acts like a âsingle source of truthâ for construction data, which helps transportation agencies make data-driven decisions related to the construction programs. All the AASHTOWare Project Modules and products work seamlessly together and have the same look and feel to promote standardization throughout different project phases. This type of software offers a more accurate calculation of costs, analysis of bids, and tracking of materials and assets than paper-based methods. It seeks to reduce data errors through automatic system checks and verifications and managing duplicate information, as well as making the data more accessible and consistent. It can improve productivity, reduce costs, improve time management, improve inspection procedures, optimize labor strategies and labor payroll, and enhance safety records (AASHTOWare Project 2021). While the benefits of construction administration software are plenty, implementation requires significant financial investments and training of workers on software, as their ability to input quality data is vital. Resistance to change and the overhaul of traditional construction administration systems remain challenges as well (Ahmad et al. 2017). Also, just like with electronic document management (EDM), there are legal issues that can arise, including data ownership, as well as the fact that there are no standardized procedures related to construc- tion administration in case of legal disputes among stakeholders (Christensen et al. 2007; Guo et al. 2017). 2.7 Mobile Devices for Inspection and Acceptance Mobile devices, such as tablets, are electronic handheld devices that are used to collect and input data on transportation projects. Specifically, they are useful in field inspection and accep- tance (Xu et al. 2019). Mobile devices can also be integrated with global navigation satel- lite system (GNSS) devices to allow for the capture of geospatial information of assets. Mobile devices can use BIM data to fully utilize their potential. For inspection purposes, mobile devices can allow for all inspection tasks and locations to be predetermined for the inspector before the inspection. They can also allow for the retrieval of all relevant information and data related to assets being inspected. It also offers the inspectors an easy and straightforward automated process to fill the inspection forms and ultimately provide approval or rejection (Tsai et al. 2014). Mobile devices, when used for inspection, can be beneficial, according to Valdes et al. (2013). The current practices of recording and filing field inspection data are mostly paper based and require the manual process of entering data on paper forms in a manner that is tedious and time consuming (Valdes et al. 2013). The benefits of the use of mobile devices for field inspec- tion can include improving the inspection process due to the use of standardized forms and limiting human subjectivity; enhancing the data collection and distribution process and reducing the data-entry errors by eliminating the double entry of data, once on a paper form and then
Literature Review 11  on a computer; elimination of paper use, which is an environmentally friendly solution; offer- ing real-time data access to inspection documents; increasing transparency in the inspection process; increasing inspection work efficiency; and reducing time delays and inspection costs (Valdes et al. 2013; Weisner et al. 2017). Despite the numerous benefits of the use of mobile devices for inspection purposes, challenges include the need for a major initial investment and the training of workers on the use of this technology. Resistance to change and hesitancy in the adoption of new technology are also barriers (Ahmad et al. 2017). 2.8 Reality Capture Reality capture is the process of creating virtual 3-D models of real-world objects by scanning or photographing objects from multiple angles. In construction, LiDAR, which is a laser 3-D scanning technology, uses laser beams to collect data about the distance to points on surfaces within its range field, and the collected data is used to create 3-D point clouds (Technical University of Denmark 2019). In transportation construction, reality capture technology is used for surveying ground surfaces to capture the on-site reality. It can also be used to create as-built 3-D models after the construction of the project, which can be used for inspection and main- tenance needs. LiDAR technology is also used for the detection of construction defects by comparing design models with the as-built model created using reality capture (Gordon et al. 2003; Zhang et al. 2006; Yan et al. 2015; Technical University of Denmark 2019). LiDAR-collected survey data can be used for a variety of purposes, including roadway-corridor mapping, roadway- improvement projects, intersection enhancements, bridge inspections, flood-risk mapping, wetland mapping, and disaster-response mapping (Vincent and Ecker 2010). The use of reality capture can be advantageous in the transportation-construction industry. Current practices of mapping road information include traditional aerial-imagery mapping and ground surveys using field crews. Such a process is time intensive and poses worker-safety hazards and traffic-congestion issues. A study by the Missouri DOT found that the use of LiDAR technology allowed for the collection of immense amounts of data that are accurate while reducing field-survey work time and limiting the safety risks to workers. Additional benefits include overall cost savings and reduced data-collection time. Also, LiDAR can be used at night when there is no traffic congestion, which reduces the number of âartifactsâ in the collected data sets (Vincent and Ecker 2010). However, there are significant limitations to be considered before the implementation of LiDAR technology. This technology requires major financial investment in the hardware and software used to process the data, which can be as high as $1 million as of 2010, when Vincent and Ecker reported their findings. Another limitation is the presence of obstructions, such as trees, building overhangs, tunnels, and under bridges, which can result in less-than-optimal detail feature requirements (Vincent and Ecker 2010). 2.9 Intelligent Compaction IC is a form of compaction process that uses rollers that are equipped with integrated measurement systems, which consist of GPS, accelerometers, infrared thermometers for HMA/warm mix asphalt feedback control, and onboard computer reporting systems (Chang et al. 2014). IC is used for compaction of soil/subbase and HMA materials, as well as for quality inspection purposes (FHWA 2014). IC is used because it allows for the con- tinuous assessment of mechanistic soil properties using roller vibration monitoring. It also allows for on-the-fly modification of vibration frequency and amplitude. This technology
12 Technological Capabilities of Departments of Transportation for Digital Project Management and Delivery provides a full GIS-based record of the earthwork site by utilizing the integrated GPS system (Mooney et al. 2010). While the successful implementation of IC has been documented for soil compaction, US highway officials are only slowly adopting the technology (FHWA 2014). The use of IC offers many benefits in roadway construction. One key finding of an FHWA study of IC across 10 state DOTs was that all state DOTs realized that IC mapping of the base helped identify weak spots and stiff areas, prior to HMA placement, as well as improving the quality of compaction. Other benefits include the optimization of labor deployment and construction time; reduced material variability; reduced compaction and maintenance require- ments; identification of noncompactable areas; ability to make midcourse corrections; main- taining construction records; generation of an IC base map; and reduction of highway repair (FHWA 2013b; Intelligent Compaction 2018). Along with these benefits, there are some issues to consider before implementation. Equip- ment cost for IC rollers is higher than conventional rollers. Additionally, the use of IC requires the training of operators and construction supervisors. Importantly, FHWA still notes that con- ventional spot tests, such as cores and nuclear-density gauge measurements, are required for acceptance (FHWA 2017b). Finally, because IC uses highly sensitive instruments for data col- lection, these instruments require constant maintenance and calibration to maintain accurate data (FHWA 2013b). 2.10 5G/Small Cell Technology Communication is the most important step for the advancement of any industry, including construction. 5G is the next generation of mobile data highway technology. 5G allows for the incredibly fast transfer of data through a network or from one medium to another (Woo et al. 2021). In transportation and highway projects, there is an exorbitant amount of data that is collected by systems, machines, or devices. However, this data is useless unless it can be transferred from the system or device that collected the data to a system where the data can be aggregated, processed, accessed, and analyzed. The collected data that can be communicated and transferred through a 5G network includes Internet of Things (IoT); RFID; wireless sensor networks; small UAS; AMG; 3-D scanning; LiDAR; AR; VR; 3-D/BIM models; and EDM. All of this data can be instantaneously transferred using 5G, to allow for real-time, on-site access of the collected data (Reja and Varghese 2019; Wolf et al. 2019; Woo et al. 2021). The use of 5G in highway construction has numerous benefits. 5G offers bandwidth efficiency that allows for large amounts of data to be transferred instantaneously to provide real-time access to information. It also allows for machine-to-machine communication, which enables autonomous machines to coordinate and communicate with each other to work more efficiently. 5G is also a more reliable network compared to 4G (Fulton 2021; Wolf et al. 2019). 5G increases productivity and significantly reduces delays and associated costs by decreasing the amount of time spent on construction data transfer (Reja and Varghese 2019). Despite these benefits, implementation and use of 5G can be hindered by the fact that it is an expensive technology. 5G is a sophisticated network technology, and developing it requires major expertise. Also, 5G networks have limited coverage, and access to a 5G network may prove difficult in remote areas (Midatala 2020). 2.11 Automated Machine Guidance AMG is a synthesis of 3-D models, geospatial technologies, like GNSS or GPS, accelerom- eters, and onboard computers and uses the data collected, including accurate horizontal and vertical positioning from these systems, to guide construction equipment during operations
Literature Review 13  (Mallela et al. 2019; White et al. 2018). In highway construction, AMG is mostly applicable on highway-transportation projects that have a large amount of earthwork or paving, locations where GNSS reception is reliable if the system used is controlled by total stations, new align- ments, and projects with a design-based digital terrain model (FHWA 2013a). State DOTs and other state agencies in the United States are recognizing more and more that bid prices are minimized when 3-D models are provided and contractors use AMG (FHWA 2013a). AMG can be quite beneficial in highway construction. This technology improves the overall quality of work by performing tasks with a higher level of accuracy and precision compared to traditional construction methods, better control of elevation and cross slope, conducting more accurate calculations for quality assurance and quantity calculation, making fewer errors that would require rework, and increased efficiency in calibration of equipment compared with string-line level. AMG can make for safer working conditions because of the lower number of workers exposed to construction equipment, can assist in staffing challenges, and can reduce the need for string lines. AMG also reduces contract time because of increased equipment productivity, requires less time surveying and staking, and improves equipment logistics due to less required rework. AMG can also reduce overall costs because of less money being spent on fuel, maintenance, operating costs, and agency costs due to increased equipment productivity, which also makes it more environmentally friendly. AMG can provide real-time feedback on the behavior of construction equipment, can make use of 3-D models during operation for more accurate construction, and a greater potential to prepare as-builts (Vonderohe and Hintz 2010; FHWA 2013a; Jalayer et al. 2015; Mallela et al. 2018; White et al. 2018; Hatoum and Nassered- dine 2020). Several field studies of AMG use demonstrated an increased rate of productivity and reduced delays (Jalayer et al. 2015). Despite its numerous advantages, AMG use or implementation presents challenges to be considered. Those include the difficulty of using and operating AMG equipment because it requires some technical sophistication. AMG is also heavily dependent on 3-D or BIM models, and many agencies have struggled to adopt 3-D modeling for several reasons, including lack of resources, lack of knowledge, and general hesitance to change. Many contractors have also found that obtaining AMG equipment involves a large financial investment. Additionally, since AMG is heavily dependent on data, inaccurate or incomplete preconstruction survey data or 3-D models could hamper its ability to operate at the desired level (Vonderohe and Hintz 2010; Jalayer et al. 2015; Mallela et al. 2018; White et al. 2018). 2.12 Augmented Reality AR is a new technology field, in which computer-generated virtual objects and information are superimposed on the userâs view of a real-world scene to produce a mixed world. This enables an immersive environment that aligns real scenes with corresponding virtual-world imagery. This overlay allows users to see additional information about the real world for the purpose of enhancing the human perception of things (Chi et al. 2013; Bilal et al. 2016). AR has a lot of applications on construction sites. MezÌa et al. found that ARâs potential applications include identifying and locating existing building component locations; supervision of com- pliance with the design; renovations; visualization of 3-D models on-site; locating construc- tion materials and equipment; locating installation instructions and guidance notes; schedule compliance; production of project documents; and operation and maintenance (2015). Wang et al. described the potential applications of AR as including visualization of design during production; spatial-site-layout collision analysis and management; linking digital information to physical resources; comparing as-built and as-planned data in a single environment; moni- toring progress of construction; and integration with procurement to track and manage material flow (2013). Oesterreich and Teuteberg stated that AR can be used for learning and training in
14 Technological Capabilities of Departments of Transportation for Digital Project Management and Delivery a risk-free virtual environment; construction-safety training; defect management; and real-time communication with on-site personnel (2016). The FHWA found that a unique application of AR is the ability to leverage the 3-D scanning hardware used for AR tracking to capture existing 3-D data in the field (2020a). AR has numerous potential benefits in construction. Those include real-time data collection; detecting design errors; educating the workforce; enhancing decision-making; enhancing spatial cognition; improving collaboration and communication; improving ownerâs engage- ment; improving productivity; improving quality; improving real-time visualization of the project; improving safety; improving the quality of planning and scheduling; providing addi- tional resources for problem-solving; and reducing waste, defects, and construction rework (Nassereddine 2019; Nassereddine et al. 2020). Despite these benefits, there are many potential obstacles to the adoption and implementation of AR. Nassereddine grouped these obstacles into five categories (2019). Technological obstacles stem from the difficulty of integration of AR with existing technology, data-privacy and secu- rity concerns, lack of maturity of AR technology, and lack of industry standards for hardware and software. Organizational obstacles include lack of management support, uncertainty of AR benefits, cultural resistance, and disruption to the rest of the organization. Human obsta- cles include the lack of skilled personnel and IT resources, resistance to change, the need for specialistsâ assistance, and discomfort with prolonged use. Financial obstacles include cost of implementation and maintenance, time and cost associated with training existing staff, and unawareness of actual in-field applications. Other obstacles include the fragmented nature of the construction industry, lack of standards to describe data and support interaction and collaboration, and lack of existing BIM workflow to augment (Nassereddine 2019).
