基于监测数据修正多尺度有限元模型的超高层转换桁架和节点内力变化规律研究

Study on internal force variation law of transfer truss and joint of a super high-rise building based on multi-scale finite element model modification by monitoring data

为克服超高层结构关键构件和节点在传统局部分析模型中存在边界误差和不能全面反映结构受力的不足,根据应变监测获取超高层结构的静力响应,分析采用非均匀温度场作用下超高层结构多尺度有限元模型的估算结果与实际结构动静力响应之间的差异,提出了基于结构自振频率、悬挑桁架和节点的温度应力系数为目标的响应面模型修正方法,在修正后的多尺度有限元模型中施加规范给定五十年一遇的风荷载,分析转换桁架和节点的局部应力变化。分析结果表明:超高层结构幕墙施工状态下温度与应力之间的相关性系数超过0.8,温度变化对构件应力影响较大,验证了以温度应力系数为目标的超高层结构响应面模型修正方法有效性,以及采用非均匀温度场作用下多尺度有限元模型分析结构局部构件内力变化的可行性。

To overcome the shortcomings of boundary errors and incomplete reflection of structural forces in traditional local analysis models for key components and joints of super high-rise structures,the static response of the super high-rise structure was obtained based on strain monitoring.The difference between the multi-scale finite element model of the super high-rise structure and the actual dynamic and static responses of the structure under the action of non-uniform temperature field was analyzed.Based on the natural frequency of the structure,the response surface model correction method with the temperature stress coefficient of the cantilever truss and joints as the target was applied to the modified multi-scale finite element model with a wind load given by the specification once in fifty years,and the local stress changes of the transformed truss and joints were analyzed.The analysis results indicate that the correlation coefficient between temperature and stress during the construction of super high-rise structural curtain walls exceeds 0.8,and temperature changes have a significant impact on component stress.This validates the effectiveness of the response surface model correction method for super high-rise structures with temperature stress coefficient as the target,as well as the feasibility of using a multi-scale finite element model to analyze local component internal force changes under non-uniform temperature fields.