Skeleton and Infill Housing Construction Delivery Process Optimization Based on the Design Structure Matrix

Skeleton and Infill (SI) housing system is considered as a significant path of sustainably prolonging building life by improving structural durability and infill variability for its nature that the skeleton system is fixed, while the infill system could be rebuilt to satisfy users' changing demands in different stage without damaging the skeleton system. The application of a SI housing system involves two new characteristics compared to traditional cast-in-place housing system: components production in factories and site construction are carried out simultaneously; the skeleton system and the infill system are constructed in parallel phases, which increase enormous parallel work. Iterations and rework would increase with the improper handling of parallel works, which lead to higher construction cost and lower participant willingness of stakeholders in SI housing construction delivery process. It is essential to establish a model to clarify the dependencies among major parallel work items and recognize parallel work sets to optimize the construction sequence for stakeholders to strengthen communication and coordination on key work items in a more efficiency way. By conducting investigations into the construction delivery process of typical SI housing projects in China, this paper developed a parallel collaborative mode based on the design structure matrix (DSM) to identify the complex dependencies among major cooperative work items. Furthermore, to provide an optimized parallel collaborative process, graph theory was introduced to find parallel work sets and eliminate repetition and iteration caused by improper work execution sequences. The results provide a guide for stakeholders to make appropriate cooperation strategies in implementing major work items and promoting cooperating efficiency by reducing iteration and rework.