Reinforced concrete (RC) products poured directly at sites or prefabricated are still popular choices in civil engineering field around the world. In the present study, prefabricated RC formwork possibly decreasing project duration remarkably and mostly keeping the monolithic behavior of frames are introduced. A RC prefabricated formwork system not only plays the same role as classical kinds of formwork, particularly wood, plastic or steel but also contributes to the strength of structures. The natural characteristics and the nonlinear performance of a single three-dimensional frame built using a RC formwork system are evaluated by comparing with those of a reference frame constructed traditionally. The natural frequencies are determined experimentally using shaker test and by numerical modeling using finite element method (FEM) whereas the nonlinear performance of the structures is computed by nonlinear static pushover analysis (NSPA) using the software package ABAQUS (2013). Based on the results of the empirical vibration test and numerical modeling, the natural characteristics of both structures are approximately similar to each other. However, in case of nonlinear performance, although the frame built using the RC formwork system performs a lower bending capacity, about 70% of the ultimate flexural strength of the monotonic frame, its ductility ratio is higher, 13.3% in comparison with 8.2% of the classical frame.
Keywords: Concrete-to-concrete interface, RC Formwork, Shaker Test, natural characteristics, Pushover analysis