摘要
由于反拉双曲空间网格钢结构通过向下张拉主桁架产生预应力,并在卸除张拉力后由主桁架带领劲性索回弹而完成主体结构预应力的施加,施工工艺复杂且尚无类似工程实例,为了确保主桁架顺利卸载,保障施工过程安全,通过数值模拟分析了主桁架临时支撑拆除全过程中应力、挠度变化情况,并同现场监测结果进行比对,分析了临时支撑拆除前、后对主桁架的影响。结果表明:在施工阶段,有限元分析结果与监测结果基本吻合;施工过程中,拆除临时支撑后关键杆件产生了应力突变,且在拆除临时支撑1 d~2 d后杆件应力、挠度趋于平衡;温度对主桁架应力、挠度影响较大,在施工过程中不可忽略温度应力对结构的影响。该研究可为后期设定健康监测预警值提供工程经验。
Due to the fact that prestressed force of the main structure is generated by the downward tension of the main truss in the reverse tension hyperbolic space grid steel structure,and the main truss leads the rigid cable to rebound after the tension is removed,the construction process is complex and there is no similar engineering example.In order to ensure the smooth unloading of the main truss and the safety of the construction process,the stress and deflection changes in the whole process of the removal of the temporary support of the main truss are analyzed through numerical simulation,compared with the field monitoring results,the influence of the removal of temporary support on the main truss is analyzed.The results show that in the construction stage,the finite element analysis results are basically consistent with the monitoring results.During the construction process,the stress mutation of the key members occurred after the removal of the temporary support,and the stress and deflection of the members tended to balance after the removal of the temporary support for 1~2 days.Temperature has a great influence on the stress and deflection of the main truss.The influence of temperature stress on the structure cannot be ignored during the construction process,and it also could provide engineering experience for setting the early warning value of health monitoring in the later stage.
作者
叶李斌
YE Libin(Fujian Yongzheng Engineering Quality Testing Co.,Ltd.,Fuzhou,Fujian 350012,China)
出处
《水利与建筑工程学报》
2022年第5期210-216,共7页
Journal of Water Resources and Architectural Engineering
基金
福建省建设科技研究开发项目(2022-K-66)。
关键词
大跨钢结构桁架
数值模拟
施工过程
健康监测
预警值
long span steel truss structure
numerical simulation
construction process
health monitoring
early warning value
