ABSTRACT

The paper focuses on the analysis of actual bending moments in RC walls of high-rise structures. A comprehensive analysis was carried out on three concrete buildings in order to evaluate the accuracy of the procedure for obtaining bending moments proposed by Eurocode 8 (EC8). The buildings are designed according to EC8 for medium ductility class (DCM) and high ductility (DCH). Nonlinear 3D models of the selected structures were subjected to 60 strong earthquake ground motions recorded on rock and stiff soil. One hundred and eighty nonlinear time-history analyses (NTHA) are carried out to compare the actual bending moments against design EC8 bending moments. Based on the findings of the conducted study, the possible improvement of EC8 bending moments design envelope for RC walls of high-rise buildings is indicated. A simple proposal for the correction of the existing EC8 bending moment envelope is introduced by its modification over the height of the wall to account bending moment increase due to the higher mode effects and by substituting EC8 design moment with wall resistance moment at the base. This improved envelope better matches the actual bending moments in RC walls of high-rise buildings. Further calibration is clearly required.

摘要

本文重点分析高层结构钢筋混凝土墙的实际弯矩。为了评估获得欧洲规范 8 (EC8) 提出的弯矩的程序的准确性，对三座混凝土建筑物进行了综合分析。建筑物的设计符合 EC8 中等延展性等级 (DCM) 和高延展性 (DCH) 标准。所选结构的非线性 3D 模型经受了在岩石和坚硬土壤上记录的 60 次强烈地震地面运动。进行了 180 次非线性时程分析 (NTHA)，以将实际弯矩与设计 EC8 弯矩进行比较。根据所进行的研究结果，指出了可能改进高层建筑 RC 墙的 EC8 弯矩设计包络线。一个简单的修正现有 EC8 弯矩包络的建议是通过修改墙的高度来考虑由于更高的模式效应而导致的弯矩增加，并通过在底部用墙阻力力矩代替 EC8 设计力矩来引入。这种改进的围护结构更好地匹配高层建筑钢筋混凝土墙的实际弯矩。显然需要进一步校准。