Study the relative contribution of materials, reinforcement and concrete layers at different levels of cyclic deformation of masonry walls reinforced with shotcrete

Abstract

In masonry buildings, walls are the main structural members that deal with lateral forces. The important point in seismic retrofitting projects is identify the most effective method of improving in various levels of displacement. Therefore, in this study based on laboratory results, 12 reinforced and unreinforced walls are subjected to cyclic load, and based on the optimum values for the calibration parameters modeling results with available experimental results, in first step, with change in the specification of reinforced and unreinforced walls, An estimate of the contribution of each component in the improvement of three displacement levels, displacement in the yield point, displacement corresponding to the maximum resistance and the final displacement is made. In the second step, with change in the thickness of the layer masonry materials in unreinforced brick walls and, with change in the thickness of the masonry, concrete, diameter rebar and the distance between the bars, in reinforced brick wall, analytical values are determined. Finally, in the third step the amounts proposed in first step is compared with the amounts extracted in step two that have been derived analytically. In unreinforced walls computing values for the share of masonry materials resistance in three levels of displacement is estimated at around 97%. In reinforced and unreinforced walls the most share in resistance in displacement of the yield point and displacement corresponding to the maximum resistance was for concrete. In the final displacement limit in one way reinforced walls, the most share is for resistance has for masonry material and in two way reinforced walls, the most share is for resistance has for reinforcement. Average computing error of the analytical values obtained from step two in the walls was, about 7.5% is obtained.

Keywords

• unreinforced wall
• levels of deformation
• concrete layer
• network reinforcement
• shotcrete