Numerical models for masonry infilled RC frames retrofitted with engineered cementitious composites

Abstract

Reinforced concrete frames with unreinforced masonry (URM) infilled walls represent a widely adopted building system The analytical macro-model based on equivalent diagonal struts is often used to assess the infilled frames response The URM infills may increase lateral stiffness strength and energy dissipation capacity of the bare RC frame During the earthquake the infilled masonry walls are damaged prematurely due to diagonal tension and compression or out-of-plane failure A series of experiments have been performed in order to examine the impact of a thin layer of Engineered Cementitious Composites (ECC) for retrofitting infilled RC frames The purpose of this study is to develop a model to simulate the masonry-infilled RC frames retrofitted with ECC by OpenSees software The numerical model of RC frame has been considered the flexural behavior by using the nonlinear beam-column element consists of shear and rotational springs on the both sides to simulate the shear and bar sliping behavior The masonry infill wall is modelled by using a single strut element in both diagonal directions The backbone curve of masonry walls proposed by Liberatore and Decanini is adopted as the force-displacement curves in this study The ECC retrofitted layer connect to the infilled RC frame model by two node link element with infinite stiffness in three dimensions Considering the flexural and shear behavior of retrofitted layer the model use the beam-column element and shear spring The envelope curve of shear spring is based on the modified compression field theory (MCFT) Finally the comparison of simulated results and experimental results indicates that the proposed model can be used efficiently in simulating of the masonry-infilled RC frames retrofitted with ECC and to be capable of predicting the lateral force of retrofitted layer

Date of Award	2020
Original language	English
Supervisor	Chung-Chan Hung (Supervisor)