A process model for work-flow management in construction

This thesis describes a novel approach for management of work-flow in construction, based on the combination of location-based scheduling and modelling with 4D CAD. Construction planners need to carefully design a process that ensures a continuous and reliable flow of resources through different locations in a project. The flow of resources through locations, termed work-flow, and the resultant ability to control the hand-over between both locations and crews, greatly empowers the management of construction operations. Todays scheduling practice for construction work shows that planning for work-flow is deficient due to practical and methodological reasons. Focus is mainly placed on planning of transformations and flow management is not explicitly addressed, but is rather being realized as a side-product of short-term task management. In addition, todays scheduling techniques provide limited insight in the spatial configuration of construction operations, thereby limiting the communication among project stakeholders and, as a result, limiting the planning and control of work-flow. I present a novel process model for the management of work-flow in construction, which provides project stakeholders with spatial insight in the flow of construction work. The model is based on a combination of two concepts: Lean Construction and Virtual Design and Construction. The suggested process model provides mechanisms for two levels of work-flow management: macro- and micro-management. Scheduling of work-flow on a macro- level is based on a combination of location-based scheduling and 4D CAD and is suggested as an alternative to todays common discipline-oriented work breakdown scheduling approach. This level of work-flow management is best initiated in early stages of a project and aims to provide insight in the overall flow of work on a construction site. The micro-management of work- flow is intended to be an instrument in the planning and control of day-to- day construction tasks. Based on the macro-management work-flow plan, more detailed look-a-head schedules can be constructed for the purpose of micro- management where necessary prerequisites for efficient and safe execution of construction tasks can be controlled, using a space-based 4D model. Five test cases have been used to develop, apply and validate my suggested process model. The first test case is of an explorative character and provides theoretical and practical insights in the application of Virtual Design and Construction techniques. The second test is based on case one and explores modelling with 4D CAD in further detail. Test Case II suggests that data extracted from 4D models can be used in planning and analyses of construction work. Based on theoretical studies of Lean Construction and Virtual Design and Construction and results from the first two test cases I developed a process model for planning of work-flow management. The applicability of the process model is validated in the third test case. The fourth test case presents an application and validation of the suggested process model for work-flow management. Finally, the fifth test case extends and applies the developed method from Test Case III and results in a formal process description for the management of work-flow in construction. Application of the proposed process model in the test cases shows that the combined use of location-based scheduling and 4D CAD is a suitable method to plan and control work-flow. The location-based scheduling technique allows planners to gain insight in the flow of resources through locations in projects. The 4D CAD model is a valuable supplement to the location- based schedule and allows users to quickly and clearly gain insight in the spatial configuration of construction work. I believe that this and other combinations of Virtual Design and Construction methods with principles from Lean Construction can contribute significantly to the value of the end product and the reduction of waste in the construction process.