某50.4m跨门形建筑及其临时支撑施工模拟分析

Construction simulation analysis on a 50.4m-span portal shaped building and its temporary braces

以某门形高层建筑及其临时支撑为研究对象,采用MIDAS/Gen软件,按照实际施工方案建立分析模型,真实模拟了钢骨混凝土桁架内的钢骨桁架整体提升、混凝土逐层施工、混凝土强度随龄期逐步增长、混凝土收缩徐变随龄期逐步发展、临时支撑的刚度及稳定。研究结果表明,临时支撑与主体结构的受力相互影响;转换结构自身具备结构强度后,其临时支撑即使超过失稳临界承载力也不会坍塌,而是能保持一定的承载力;按线弹性假定计算会夸大临时支撑的作用,造成主体结构构件计算内力偏小,需要根据屈曲稳定分析的结果考虑临时支撑屈曲后的贡献。

A portal shaped high-rise building and its temporary braces were investigated by using MIDAS/Gen to establish analysis model according to the actual construction plans. A series of factors were truly simulated,including the integral lift of the steel in the steel reinforced concrete（ SRC） truss,the construction of concrete layer by layer,the strength of concrete increase with age increase,the shrinkage and creep of concrete developing with the age increase,and the stiffness and stability of temporary braces. The results show that there are interaction between the temporary braces and main structure; after the transfer structure has its own structural strength,its temporary braces do not collapse even if it exceeds the critical load-bearing capacity,but can maintain a certain bearing capacity; according to the assumption of linear elasticity,the effect of temporary braces is exaggerated,resulting in the smaller calculation internal force of main structural members,so the contribution of temporary braces after buckling needs to consider the buckling stability analysis results.