|Title||A Model for Managing Construction Activities and Flows|
|Publication Type||Working Paper|
|Year of Publication||2018|
|Authors||Garcia-Lopez, N, Fischer, M|
|Publisher||Center for Integrated Facility Engineerning|
|Place Published||Stanford, CA|
|Keywords||construction model, control, flow, Project Management, variability|
Construction field managers often struggle to keep projects on schedule, resulting in time and cost overruns. Schedule conformance depends on the construction activities starting and finishing on time. However, construction activities are often delayed because the construction flows necessary to start their execution are unavailable. Construction flows can be classified into: labor, equipment, workspace, materials, precedence, information, and external. Current construction models do not formally represent, measure, and track all the flows. Hence, field managers lack formal methods for managing flows and instead rely on their intuition and experience managing them. This report presents a construction model based on activities and flows, called the Activity-Flow Model (AFM). The AFM formally represents the activities, the flows, and their interactions. The AFM was validated prospectively through its implementation on three building projects that were in different phases (foundations, core and shell, and finishing), geographic locations (Bogota, Copenhagen, and Lima), and used different planning and control methods (master schedule and weekly planning, Last Planner System, and Location-based Management System). The AFM was able to represent all the activities and flows in the test projects, track the variations of the activities and flows, and quantify the activities’ and flows’ variability. Field managers can use the metrics enabled by the AFM to plan and control the project. Such proactive flow management can help field managers improve flow readiness, which should reduce activity delays and improve schedule conformance.