Experimental Study on Improved Detail Design and Analytical Study on Simulation of Retrofit by Adding Reinforced Concrete Walls with Openings

Because of 921 Chi-Chi earthquake, many elementary and secondary school buildings were seriously damaged. And it also aroused the whole nation’s concern of low affordability of the school buildings’ seismic capacity. Because dismantling old school buildings will cause serious economic losses, scholars proposed methods for increasing school buildings’ seismic performance. Adding shear wall is a popular retrofit method for school buildings. But for the lack of lighting and ventilation requirements, it is the biggest shortcoming for shear wall retrofit methods. Therefore, National Center for Research on Earthquake Engineering (NCREE) planned the retrofitted method of RC walls with opening. The seismic capacity of RC walls with opening by experiments will be shown. Following the specimens of RC walls with opening in 2015, this experiment plans three new specimens that the clear span is 420 cm. The specimen was designed in symmetric configuration. To understand the performance of specimens’ seismic capacity, the cyclic pushover test will be conducted at National Center for Research on Earthquake Engineering. The main propose of the test is to know the influence of the section design on the specimens’ performance in order to set a detail design on the retrofit of RC walls with opening. Experimental results show that with the carefulness of section design, the stiffness and toughness both increase no matter the opening is large or small. And the failure mode also turns to be better. Drift ratio of all specimens can be up to 3% with the carefulness of section design. It means that section design is important. Prediction of force-displacement curves is based on the third-edition Evaluation and Retrofit Handbook. With the analysis of the experiment results, prediction of force-displacement curves are modified. And based on the method of force-displacement curves’ prediction, two methods of RC walls with opening’s models are modeled for ETABS pushover analysis.