Multivariate regression analysis to strength and stiffness evaluation of masonry infills

Abstract Reinforced concrete frames with masonry infill are widely utilized in construction worldwide. This present study aimed to investigate the behaviour of masonry infill. Firstly, the compressive strength of the masonry infill and the evaluation methods were examined, specifically prism tests and wallette tests. The study collected a substantial database, revealing that wallette tests indicate higher stiffness compared to prism tests. Based on the findings, it is recommended to employ prism tests for assessing the stiffness of masonry and wallette tests for evaluating the compressive strength of masonry. Furthermore, the study assessed the performance of 18 empirical models to identify the most suitable model for predicting the compressive strength of masonry using the two testing methods (wallette and prism). To evaluate the strength of masonry infills under horizontal loading, a database of reinforced concrete frames with masonry infills was collected. The infill responses were determined by calculating the differences between the infilled frame and the bare frame. By employing multivariate regression analysis, equations were proposed for the various parameters of the quadri-linear relationship governing the behaviour of masonry infill. A comparison of the equations proposed in this present study with those present in the literature demonstrated their reliability.