随着装配式车站在滨海城市的建设，软弱土体对车站结构力学性能的影响成为最关心的问题之一。为此本文以深圳某装配式车站为工程背景，采用Midas-GTS有限元分析软件，建立地层-结构模型，分析了单拱大跨装配式车站的力学特征，探索了不同弹性模量、不同泊松比、不同地层条件、不同覆土厚度对地下车站结构变形、受力及接头内力的影响和规律，给装配式车站结构对地层适应性提出了理论依据和结构设计指导。结果表明：1）在泊松比不变的情况下，弹性模量对车站结构力学性能影响较大，弹性模量从15MPa增大到60MPa时，弯矩减小了44.58%；并且影响是非线性的，弹性模量在15MPa-30MPa区段结构变形较为敏感，当弹模达到45MPa以上时，敏感度下降。2）地层条件对结构顶板跨中和拱脚支座内力影响较大，强风化地层相对填土地层弯矩减少了约40%，而对侧墙内力影响较小，对BC接头影响较大。3）当地铁车站所在土层为填土时，BC接头弯矩冗余量非常小，需要对接头进行加强设计，或者对地层进行适当改良。4)在硬塑地层中，当覆土厚度从3m增加到5m时，BC接头弯矩冗余量减少了35.37%，但接头冗余量均达到29%以上，接头的安全性储备较大，接头可靠。

With the construction of prefabricated stations in coastal cities, the influence of weak soil on the mechanical properties of station structures has become one of the most concerned issues. Therefore, this paper takes an prefabricated station in Shenzhen as the engineering background, uses Midas-GTS finite element analysis software, establishes the strata-structure model, analyzes the mechanical characteristics of the Single-arch large span prefabricated station, explores the effects of different elastic modulus, different Poisson's ratio, different geological conditions and different buried depths of the station on force and joint internal force of the underground station, and gives a theoretical basis and structural design guidance for the structural adaptation of the prefabricated station to the stratum. The results show that: 1)When the Poisson 's ratio is constant, the elastic modulus has a great influence on the mechanical properties of the station structure. When the elastic modulus increases from 15 MPa to 60 MPa, the bending moment decreases by 44.58 %, and the influence is nonlinear. When the elastic modulus is 15MPa-30MPa, the structural deformation is more sensitive. When the elastic modulus reaches more than 45MPa, the sensitivity of structural deformation decreases. 2) strata have a greater influence on the internal force of the top plate span middle and bearing, and the strongly weathered geological reduces the bending moment by about 40% compared with the fill layer, while it has a smaller influence on the internal force of the sidewall and a greater influence on the BC joint. 3) when the underground station is located in the fill layer, the internal force of the BC joint is smaller. When the soil layer is fill layer, the redundancy of BC joint moments is very small, and it is necessary to strengthen the design of joints or to improve the geological appropriately. 4) Under the hard plastic geological condition , when the station burial depth increased from 3 m to 5 m. the BC joint moment redundancy decreased by 35.37%. however,the joint redundancy all reached more than 29%, and the safety reserve of the joints was larger and the joints were reliable.

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