索穹顶结构张拉找形与承载全过程仿真分析

索穹顶结构的预应力张拉过程是几何体系由机构变成结构的过程。首先，从预应力施工张拉方式实现既定结构成形态、确定结构成形态满足正常使用和安全要求、优化预应力度选定合理结构成形态三个方面，应用重启动计算分析方法，对索穹顶结构进行预应力张拉找形及承载全过程仿真分析。分析表明，采用不同的预应力张拉方式可以达到相同的既定成形态，这为制定预应力张拉施工方案创造了灵活的技术空间。其次，通过对索穹顶结构在不同预应力度下承载全过程仿真分析，得出工程采用的预应力度是安全合理的，并提出结构设计各阶段体系弹塑性性能指标。最后，针对不同跨度索穹顶结构，通过确定结构初始几何形态的初始预应力度P0，以P0为基本模数分析不同预应力度下结构的弹塑性性能，得出索穹顶结构初始预应力为（7.5～10）P0的设计方法。以上研究方法和结论在我国大陆地区首座大跨度索穹顶结构工程--内蒙古伊旗全民健身体育中心工程中实现应用。

Analysis of tension form-finding and whole loading process simulation of cable dome structure

For cable dome structure,prestressing construction process is the change of the geometrical system from mechanism to structure which can bear design load.The following aspects are considered including the prestressed cable system setting and achieving of the formed shape of structure by prestress tension,the formed shape of structure satisfying normal use and safety requirements,determining the reasonable form by optimization of prestressing degree.Prestress tension form-finding and simulation of whole loading process were analyzed through restart analysis for cable dome structure.Firstly,as prestress tension methods has no influence on the final formed shape of structure by analyzing prestress tension simulation for cable dome structure,a flexible technical space will be created for construction unit formulating plans of prestress tension.Secondly,the whole process simulation under different prestressing degrees was performed to obtain performance control indexes at each stage.The prestress rationality and safety of structure were determined based on the conclusions for the project.At last,the initial prestressing degree P0 that can keep the initial geometric form was determined.The research shows that the initial prestress P0 of 7.5~10.0 times as the design prestress is the safe and reasonable choice by analyzing the elasto-plastic ductile performance of different span cable dome structures under different prestressing degrees.The research methods and conclusions was used in design of large-span cable dome structure,which is roof structure of the National Fitness Center in Ejin Horo Banner,Inner Mongolia,first built in mainland of our country.