Strut-and-tie model for waffle slabs

摘要

Strut-and-tie model is being used increasingly for analysis and design of concrete structures withrnpronounced D-regions in the recent years. In strut-and-tie model the load carrying mechanism of a structuralrnmember is approximated by means of struts representing the flow of compressive stresses and ties representingrnthe flow of tensile stresses which enables a direct visualization of the stress flow in the structural member to therndesigners.Waffle slab is an attractive and economical alternative as compared to solid and voided slab system.rnWith a grid of intersecting ribs it essentially forms a D-region and currently numerical and empirical approachrnis used in the analysis and design of waffle slabs. A new three dimensional strut-and-tie model is proposed forrna rational analysis and design of waffle slabs and to predict the strength and mode of failure of these slabs.rnThe proposed strut-and-tie model shows good correlation with experimental results from literature. Also newrnsoftware “STWAF” is developed for design of waffle slabs using strut-and-tie model.