Nonlinear seismic response of reinforced concrete structures

This paper analyses Reinforced Concrete buildings subjected to seismic vibrations using nonlinear structural dynamic analysis. The structures under study are model Reinforced Concrete structures (2 to 10-storied) satisfying the Bangladesh National Building Code (BNBC). The buildings are subjected to recorded ground motions from the Northridge earthquake in USA (1994) and Kobe earthquake in Japan (1995). The nonlinear moment-curvature relationship of arbitrary Reinforced Concrete cross-sections is developed numerically using nonlinear stress–strain relationships for concrete and steel. Parametric studies show the effect of typical axial loads on the flexural behavior of column to be significant. Results show the importance of threedimensional analyses. Using the nonlinear sectional properties thus obtained, the nonlinear structural dynamic analyses of the buildings are performed. Results from the analyses show that many of the buildings will suffer significant damage when subjected to such severe seismic vibrations.