泡沫回填土作用下无柱大跨地铁车站受力特征分析

The Mechanics Characteristic Analysis of the Large Span Subway Station Without Pillars Under the Bubble Back-Filling

为了研究在泡沫回填土地铁结构上使用的可行性,首先选取南宁某无柱大跨地铁车站为研究对象,用sup2000对不同种类的回填土下的地铁车站结构建立平面模型,研究泡沫回填土作用下无柱大跨地铁车站的受力特征,模拟地铁车站结构在泡沫回填土作用下顶板、中板、底板以及侧墙的受力特征和变形规律。然后利用MIDAS.GTX.NX软件,建立了土与结构共同工作的三维有限元模型,进一步分析其受力特征。研究发现:采用泡沫回填土可有效减小地铁车站顶板应力,而对车站中板应力的影响较小;采用泡沫回填土时,地铁车站结构的竖向位移显著减小。

In order to research the feasibility of using the bubble back-filling into the subway structure, the large span subway station without pillars in Nanning is chosen to be the research object at first.The planar modal of the subway station under the different bubble back-filling soil are set up by the software SAP2000. The mechanics characteristic analysis of the different structures are carried out. The mechanics characteristic and the deformation rules of the subway station under the different bubble back-filling are stimulated of the top plate, the middle plate, the bottom plate and the side wall. Then the three dimensional finite model is set up by software MIDAS.GTX.NX in which the cooperative function of the soil and the structure is considered. The mechanics characteristic is studied any further. It can be inferred from the analysis results that the stress of the top plate of the subway station is reduced effectively, but the influence on the middle plate is not too much. The vertical displacement of the subway station is reduced effectively when the bubble back-filling is adopted.