洞柱法地下车站施工阶段的全量法与增量法对比分析

Comparative Analysis of Total Load Method and Incremental Method at the Station Construction Stage by PBA

以在建北京地铁12号线地下3层、双柱、3跨洞柱法车站为例,利用Midas Gen软件建立二维计算模型,并针对车站结构大拱、负一层中板、负二层中板、底板等施工完毕的4个工况分别采用全量法与增量法进行了构件内力分析计算,对比了2种计算方法在相同施工阶段中构件内力的计算结果。其中:拱部弯矩、侧墙弯矩、中板弯矩、中柱轴力的最大差异百分比分别为-52.36%、-105.52%、57.12%、-5.91%;使用Midas GTS软件建立了三维分析模型,比较了2种计算方法与三维分析模型的结构变形特征;通过对二维和三维模型计算结果对比分析与讨论,证明全量法与增量法在洞柱法地下车站施工阶段构件内力计算中的差异不可忽略。因此,为了保证工程设计的准确性与安全性,应采用增量法对洞柱法地下结构进行施工阶段内力分析。该研究成果可为类似结构工程设计提供参考。

Based on a station with 3 underground floors double columns and 3 spans of Beijing Metro Line 12,which is constructed by pile-beam-arch method(PBA),four construction completion of the structural arch,middle slabs of B1,middle slabs of B2 and base slab were analyzed by total load method and incremental method respectively.The calculation results of the members forces are compared at the same stage by 2 methods.And the maximum difference percentage of bending moment of arch,side wall and middle plate,and the axial force of middle column are-52.36%,-105.52%,57.12%and-5.91%respectively;Furthermore,a 3D analysis model is established by Midas GTS to compare the structural deformation by different calculation methods;By the analysis and discussion of 2D and 3D models,the results shows that the difference between the calculation results of total load method and incremental method cannot be ignored.For the accuracy and safety of the engineering design,the incremental method is more appropriate to analyze the construction force for PBA station.The research result can provide reference for the design and construction of similar structures.