Strength, deformation capacity and failure mode of RC walls in cyclic loading

TitleStrength, deformation capacity and failure mode of RC walls in cyclic loading
Publication TypeConference Paper
Year of Publication2014
AuthorsGrammatikou S, Biskinis D, Fardis MN
Conference Name4th International fib Congress and Exhibition
Conference LocationMumbai, India
Accession Numberpaper no. 408
Abstract

A database of 621 cyclic tests of RC walls is utilized to evaluate past models for the cyclic strength and deformation capacity of the wall and to develop/calibrate new ones. From the observed damage the failure mode is classified as in flexure, diagona
l tension or compression before or after flexural yielding, or in sliding shear. Past models being evaluated on the basis of the tests include models proposed by two of the authors and adopted in Eurocode 8-Part 3 and/or MC2010 for (a) flexural strength, (b) the cyclic shear strength after flexural yielding (as affected by the imposed ductility demand) and (c) the cyclic chord rotation capacity in flexure. Walls with height-to-length ratio less than 1.2 are considered separately, as their shear failure requires different models: past models are commented and a new one proposed and calibrated on the basis of 130 cyclic tests of squat walls. Past models for sliding shear strength are evaluated and modified on the basis of 29 cyclic tests with that failure mode: a new model is proposed for the possibility of uncontrolled sliding during a load reversal at a point in time when the flexural crack at the base is open throughout the section and only dowel action of the still elastic vertical bars is available to resist the shear force. There is good agreement of the predicted cyclic strength and/or deformation capacity per failure mode; the prediction of the most likely mode in the tests of the database is also satisfactory.