The purpose of member design is to assure that the strength and the ductility of a member are greater (equal) than (to) those required in structural design of a building under the considered load condition. Therefore, the reliable estimation of required strength and ductility in structural calculation is of importance as well as the accuracy of design equations for strength and ductility. In shear design of a primarily earthquake resistant member, maximum induced shear force and hinge rotation angle during severe earthquake excitation are essential to be estimated. For those required member performances, each constituent member is designed for shear. However, in current design procedure indicated in the Building Law of Japan and relating regulations the required performances of constituent members for shear is not clear as well as the structural performance of whole buildings. In this report, current design procedure for shear is briefly introduced and some problems involved in it is also pointed out on the basis of above mentioned viewpoints. They are mainly clue to the allowable stress design method where the design shear force and required ductility of plastic hinge region would not be properly estimated at the ultimate limit state of a building. In near future, the limit state design method would take place of the allowable stress design method, where the rational and consistent shear design method of constituent members is required on the basis of the reliable calculation method for design shear force and accurate shear design equations.
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