An Equivalent Step-By-Step Post-Elastic Analysis for Multi-Storey R/C Buildings with Masonry Infills

摘要

In this paper different modelling techniques for thesimulation of masonry infill panels inside R/C framestructures are investigated in an effort to develop a modelthat can capture the non-linear behavior of masonry infilledR/C frames when infill panels of different technicalcharacteristics, configurations and details are adopted. Twotypes of numerical simulation techniques for the masonryinfills are adopted, namely a macro-modelling technique andsimulation where the masonry infill and the joint interfacebetween the surrounding frame and the infill is representedby a diagonal strut model. And, inelastic finite elementsimulations are employed, including stiffness and strengthdegradation. This is done by simulating the inelasticbehavior of the masonry infill, the formation of plastic hingesfor the R/C frame at pre-defined locations and the sliding orseparation of the masonry infill from the surrounding R/Cframe. The paper then deals with the applicability of thishopefully “successful” non-linear masonry-infill concreteframenumerical simulation to predict realistically the inplaneseismic behavior of prototype multi-storey R/Cstructural frame formations with masonry infills. In order toovercome the computational time and memoryrequirements, use was made of an equivalent post-elastic“pushover” type of analysis that draws information from thestiffness and strength variation from multi-bay, one-stoeryR/C masonry infilled unit frames that compose a given multistoreystructural formation. In doing so, the fully non-linearnumerical simulation of the single-storey, multi-bay units,that compose this structural formation, presented, is utilized.In what follows, it is shown that the proposed “equivalentpushover analysis” is successful in predicting reasonablywell the “top storey versus base shear” response of a 6-storey structure and the formation of failures along themasonry infill walls of the same structure.