Automated Rebar Constructability Diagnosis

In spite of impressive progress in project modeling and computer-integrated construction, there is little real integration—manual or computerized—between design and construction of building projects. Consequently, constructability problems are experienced during the construction phase. With regard to rebar, constructability problems are discovered either after casting the reinforced concrete element or not at all, resulting in a weaker element. This paper describes a rebar constructability model, which was developed in an object-oriented graphic environment. The model is intended to be used during the design phase to automatically diagnose potential rebar-related constructability problems (the Diagnosis Module), as well as to offer solutions and implement them (the Correction Module). Of these two modules, the Diagnosis Module was implemented in a concept-proving prototype. The proposed model searches for constructability problems through all relevant parts of the building. This search includes the structural design, as well as other building systems (e.g., sanitary, drainage, HVAC). The model also checks for potential collisions between reinforcement bars and temporary inserts (e.g., form ties). Thus, in addition to the resulting increased constructability, the model also has potential as a system coordination tool.