Abstract: Automatic generation of construction sequence from CAD model is a prerequisite for evaluating constructability of capital projects. Unfortunately, traditional studies for deriving construction sequence can not adequately capture or incorporate some necessary concurrency relationships. This paper proposed a new concept of construction state, and uses 14 types of interval-to-interval temporal relationships, resulting in that both precedence and concurrency relationships can be semantically depicted. Moreover, this paper further developed two types of construction sequencing knowledge: state chain type for a single building component and state interaction type for two components. Both knowledge types, which can be represented using Express language, are compatible with the IFC standard, and can also be embedded into IFC-CAD model.

Key words: computer aided design model, construction schedule, construction sequence knowledge, construction state, concurrency relationship