Tracking work-in-progress on construction sites requires establishing two-way flow of information between project managers and field personnel so that changes and performance issues with respect to task assignments, scope, status, and completion can be communicated effectively. Recent research has focused on minimizing decision bottlenecks and lowering coordination costs caused by inefficiencies in information sharing between project participants via leveraging 4D BIM and mobile computing platforms. Nevertheless, effective communication of who is doing what work in what location and comparing actual and planned progress in a timely fashion still requires preparing/updating 4D BIM with details that can reflect daily tasks, breaking the model into various locations, and then capturing task information onsite and manually updating them to 4D BIM. To address these inefficiencies, this paper presents a web-based work tracking system that builds on 4D visual production models, generated via superimposing image-based 3D point clouds with 4D BIM. These models allow project participants to directly commit to work tasks without the need for addressing difference in the level of detail between 4D BIM and actual work in progress, communicate performance deviations based on commitments from coordination sessions, measure readiness of the upcoming tasks based on inter-dependencies of current schedule tasks and their constraints, and highlight locations that are at-risk of potential performance problems. The benefits of the system in providing enhance awareness of ongoing work and better flow of information are discussed based on experiments conducted on a large-scale construction project.
INTRODUCTIONThe increasing complexity of construction projects has made it extremely difficult to accurately predict key construction performance indicators, such as the project schedule and cost (Ham et al. 2016). It is no surprise that many owners are continuously looking for project delivery methods that provide more predictable project outcomes. Among the most important advancements in construction delivery methods that can bring accountability and predictability to project performance are lean methodologies and building information modeling (BIM). Hence, several construction companies have devised workflows and deliverables that integrate BIM and lean to help teams be more accountable as planners and builders. Nevertheless,