Calculation of the required shear wall amount for strengthening of reinforced concrete buildings

A trial and error procedure are generally followed to determine the shear wall amount required to strengthen reinforced concrete buildings. For this reason, the aim of this study is to calculate the shear wall amount required for strengtheningbefore a structural analysis is made using simple equations. Accordingly, different amount of shear walls with several thicknesseswere designed and placed at several locations of artificialplans and their effect on thoseartificial buildings were examined. After the structural analysis, it is found that if the amount of shear wall is increased keeping the shear wall ratio the same, shear and moment effectiveness of those shear walls reduce. Having reduction in shear wall effectiveness, the amount of lateral forces transferred to the other load carrying members increase which results in damage in those members. Considering the results of the structural analysis, the amount of shear walls required for strengthening of reinforced concrete buildings is formulized and using these equations 15 buildings damaged during 2011 Van Earthquakes having different number of stories, plan areas and material properties were strengthened. Seismic performance of all the strengthened buildings were sought considering the 2007 Turkish Earthquake Resistant Code criteria, and it was found that the targeted performance level can be attained with the proposed equations. It can be said that, it is possible to determine the required shear wall amount for strengthening when the number of stories, soil properties, plan area and material properties of a building is known.