Strength, deformation capacity and failure modes of RC walls under cyclic loading

Past models for the cyclic strength and deformation capacity of reinforced concrete walls are evaluated and new ones are developed using results from 866 wall tests. On the basis of the observed damage, the failure mode is classified into the following categories: in flexure, in diagonal tension, in diagonal compression, or in sliding shear. Among the past models evaluated are those proposed by two of the authors: (a) for the cyclic strength in diagonal tension after flexural yielding or in diagonal compression and (b) for the ultimate chord rotation capacity under cyclic flexure, which were adopted in Eurocode 8-Part 3 and in fib Model Code 2010. Walls with height-to-length ratio <1.2 (“squat”) are considered separately: past models are evaluated and two new ones are proposed on the basis of 321 cyclic tests. Past models for sliding shear strength are modified, using the results from 55 cyclic tests. The predictions for the failure mode and the cyclic strength and/or deformation capacity agree well with the tests.

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