大断面铁路隧道室内模型试验与分析研究
Analysis and research on laboratory model test for large section railway tunnel

为研究隧道在受压破坏时，衬砌的受力特性与变形规律，采用石膏来模拟隧道衬砌，通过在关键测点布置土压力盒、应变片与百分表，监测模型衬砌的压力、应变与位移，并对监测数据进行分析。研究结果表明：各测点的围岩压力和初衬与二衬间接触压力都以压应力为主，且应力最大值出现在左仰拱拱脚、左右拱腰与仰拱拱底的位置；模型主要受到压应变，且模型衬砌内表面更容易破坏；隧道模型拱顶的沉降最大，在施工时对拱顶沉降的监测是有必要的；当隧道受到较大压力时，很可能会造成仰拱开裂。
In order to study the stress characteristics and deformation of lining, when the tunnel is under pressure, the laboratory model experiments using gypsum to simulate the tunnel lining, Through the arrangement of pressure box, strain gauge and dial indicator on the sky point, to monitor the pressure, strain and displacement of the lining of the model, and analysis of monitoring data. The results showed that: surrounding rock pressure and stress between the first linings and the second linings of full measuring point are mainly based on compressive stress, and the maximum value of stress is in the position of the arch foot of the left arch, the hance and the bottom of the invert; The model is mainly subjected to compressive strain, and the inner surface of the model lining is more easily damaged; The settlement of vault is the biggest, so it is necessary to monitor the vault settlement during construction; When the tunnel is under great pressure, it is likely to cause the inverted arch cracking