Developing a bolted moment connection system for precastreinforced concrete members

As is known, reinforced concrete structures are built as cast-in-place or precast. Due to the monolithic form of cast-in-place structures, transferring internal forces can be easily transferred among structural members. However, they have disadvantages such as long construction duration, quality problem of material or labour and not being demountable. Precast structures are built by using two different way called dry connection (not demountable) and wet connections(demountable). At present, dry precast connection systems have complex geometries. Therefore, it is difficult to construct and they may require special workmanship (post-tensioning, welding). And the complex geometry leads complex structural behaviour. Thus, special design skills are needed. Accordingly, in this study, it is aimed to develop a precast connection system that has a simple geometry, which is easy to assemble and has a monolithic-like structural behaviour. The innovative aspect of the proposed connection system is that it allows the construction of precast structures that have all the advantages of monolithic and precast structures at the same time. Thus, a new construction technique will be created. By using this technique; prefabricated, demountable structures can be built. Also, these structures can be as ductile as monolithic ones and members of this structures can be easily replaced when it is damaged. And they can be designed using monolithic design procedures. In the study, the proposed connection systems for foundation-column, column-beam, beam-beam connections were examined experimentally and analytically, and similarities of structural behaviour with monolithic connections were exhibited. As a result of the study, it was determined that the proposed precast connection system exhibited very similar behaviour to monolithic connections with respect to rigidity, strength and ductility in all three connection types. With future experimental and analytical studies, it seems that it is possible to optimize the connections and initiate the application of this concept in construction industry.