大跨度高净空盖梁支撑体系比选与力学性能研究

Comparison and Selection of Support Systems and Mechanical Properties of Long Span and High Clearance Bent Cap

针对暮坪湘江特大桥涉水引桥盖梁大跨度、高净空的特点,考虑施工便利性、安全性及可操作性,对抱箍法、支架法、抱箍+支架组合支撑体系施工法进行综合比选。采用Midas/Civil软件对不同支撑体系受力、变形进行分析,并与监测数据进行对比,结果表明组合支撑体系受力、变形均满足要求,最终选用该体系进行施工。采用组合支撑体系时,立柱直接支撑于系梁上,抱箍支点解决了主梁端部挠度过大的问题,且无须单独设置独立基础,解决了受限空间下水中盖梁施工难题。

According to the characteristics of large span and high clearance bent cap of the wading approach bridge for Muping Xiangjiang Specially Long Span Bridge,and considering the convenience,safety and operability of construction,the construction methods of hold hoop method,support method,hold hoop and support combination system are comprehensively compared and selected.This paper uses Midas/Civil software to analyze the stress and deformation of different support systems,and compares the calculation results and monitoring data.The research results show that the stress and deformation of the combined support system meet the requirements,and the combined support system is selected for construction.When the combined support system is adopted,the column is directly supported on the tie beam,and the hold hoop fulcrum solves the problem of excessive deflection at the end of main beams,and it is unnecessary to set an independent foundation alone,which solves the construction problem of underwater bent cap in confined space.