A novel construction scheduling framework for a mixed construction process of precast components and cast-in-place parts in prefabricated buildings

Abstract

The mixing of precast components and cast-in-place parts is a major feature of prefabricated buildings , but the existing pattern-based scheduling methods lack consideration of it. The main objective of this paper is to describe the mixing construction process of precast building faithfully, and schedule the process in a single BIM environment. This study presents a novel scheduling framework for prefabricated buildings. By using IFC, flexible work break-down structure (WBS) and constraints based simulation (CBS) method, this framework integrates scheduling information in a single BIM model, and organizes construction process in a flexible WBS structure to consistent with the mixing construction of precast and cast-in-place, and finally generate valid schedule to meet various constraints by using CBS. A case study is conducted to verify the framework, and a comparison with the traditional method is carried out. The result shows that this scheduling framework can faithfully scheduling the mixed construction process at different scale in a single BIM environment, and the comparison with traditional way shows it reduces the scheduling burden, improve the resources usage efficiency. This study contributes to solving the knowledge gap of the inapplicability of the process pattern-based method in describing the mixed construction process, and the heterogeneous and scattered information sources in scheduling. This methodology can conveniently organize large amount of mesoscale tasks into mixed scale task network, and facilitate the reuse of scheduling-related knowledge, improve the resource usage efficiency, help managers understand the construction process at different scales, improve the BIM-based information collaboration in scheduling. In the future, a faithful construction process description at the activity level can digitalize the actual construction process, pave the way to apply the activity data obtained by ICT. ● The existing scheduling method cannot truly reflect the actual construction process of the fabricated components and cast-in-place parts hybrid building. ● This paper presents a novel scheduling framework that schedule the mixed construction process at different scales in a single BIM environment. ● Organized in flexible WBS structure, the generated schedule could be detailed to the activity level while conform to the large-scale tasks at the same time. ● The results show that this methodology could reduce the scheduling burden, improve the resources usage efficiency; and facilitate the reuse of scheduling-related knowledge.