2014-08-24, Schuler, Harald, Trost, Burkhart

This paper presents a mechanical model which is used to analyse the sliding resistance at the cold joint of nearly quadratic basement walls. The analysis is done on a building with a height of 40m and a basement wall size of 4m x 4m. In the parameter study the axial force and the reinforcement ratios, at the boundary and in the web, are varied. Analysed are the resistances of aggregate interlock, dowel action and the shear resistance of the reinforcement which is under compression. The study shows that for a quadratic wall in most cases, failure due to sliding occurs before the maximum flexural deformation is reached. Thus the flexural ductility, e.g. in pushover analysis, is overestimated when the anchorage lengths of the structural wall is short. Therefore it is recommended for squat walls to take a previous sliding failure into account in a performance-based earthquake analysis.

2014-08, Trost, Burkhart, Schuler, Harald, Stojadinovic, Bozidar

This experimental investigation addresses the sliding behaviour found to occur in reinforced concrete shear walls under earthquake loads. This investigation compromises a series of 13 compact specimens. The tests were conducted in a biaxial test setup. The test sequences were designed to mimic the load and displacement history of a portion of the squat wall under horizontal cyclic loading. The specimens were pre-cracked up to a defined crack width. Next, diagonal compression was applied. Through the variation of the reinforcement ratio, the initial crack width, the number of cycles and the amplitudes, the effects of aggregate interlock, dowel action and shear friction in the crack were quantified. In this paper we will present the observations and the results of the cyclic tests on the core specimen group and on the monotonically tested specimens.