Spatial analysis of damage evolution in cyclic-loaded reinforced concrete shear walls

Abstract

This paper introduces a probabilistic framework to quantify the spatial distribution of cracking and crushing in rectangular reinforced concrete shear walls at different drift ratios. In this research, a comprehensive probabilistic spatial analysis is conducted on an extensive collected database of reinforced concrete shear walls tested under the quasi-static cyclic loading. The database includes 235 images of 72 damaged walls with various geometry and material properties at different drift ratios between 0.0 and 4.0%. Various image processing filters are implemented to the images to highlight the wall areas that are more prone to cracking and crushing. Then, advanced statistical analysis is carried out at the post-processing phase in order to quantify the spatial distribution of the damage. The results of the probabilistic analysis are presented for three major classes based on the variation of the wall aspect ratio. The damage heat maps are produced for each class, which show the concentration and severity of the occurred damages. In the following, statistical mixture models have been used to formulate the spatial variation of the damage over the 2D space of the concrete shear walls. A set of nonlinear predictive equations are also proposed to predict the probability of cracking at any specific zones of the walls based on the wall drift ratio. A major contribution of this study is to propose a visual benchmark for the inspectors to predict the peak-experienced drift ratio of a damaged wall (especially after a terminated cyclic-load) based only on the ultimate spatial distribution of damages. Therefore, the presented framework plays a crucial role in determining the post-hazard status of reinforced concrete shear walls based on the prediction of the peak drift ratio.