为分析局部超载作用下不同结构参数对管廊受力变形的影响，采用有限元计算软件建立新型管廊结构的三维力学模型，对锚索预应力、地基基床系数以及接缝摩擦因数等参数进行研究。研究结果表明： 1）局部超载作用使受压区管节与周边管节之间产生沉降差，相邻管节之间变形缝主要以错台变形为主。2）下层管节接缝有略微的张开现象，张开量相对较小，为1.00~2.00 mm，能够满足管廊的接缝防水要求。3）地基基床系数是提高结构整体纵向刚度、控制结构局部沉降最重要的因素。当基床系数由20 000 kN/m3降低至2 500 kN/m3，上层管廊顶板最大沉降量由3.53 mm增加至17.03 mm，最大错台量由1.11 mm增加至6.89 mm； 下层管廊底板最大沉降量由3.05 mm增加至16.55 mm，最大错台量由0.81 mm增加至6.88 mm。4）通过增大管节之间的锚索预应力，能在一定程度上提高管廊的整体纵向刚度。当预应力由0 MPa增加至230.0 MPa，上层管廊端最大沉降量由5.74 mm减小至4.42 mm，接缝错台由2.05 mm降低至0.71 mm。5）提高管节之间的摩擦因数对结构沉降和接缝错台的影响相对较小，当摩擦因数由0.5增加至0.8，最大沉降量从6.06 mm下降至5.22 mm，最大接缝张开量由1.45 mm降低至1.36 mm，对提升管廊纵向刚度的贡献十分有限。
To investigate the effects of various structural parameters on the stress and deformation of utility tunnels under local overload conditions, a three-dimensional mechanical model of a novel utility tunnel structure is established using finite element analysis (FEA) software. The main parameters studied include anchor cable prestress, foundation subgrade reaction modulus, and joint friction coefficient. The findings are as follows: (1) Local overload induces settlement differences between the loaded segments and the adjacent segments, and the deformation at joints between neighboring segments is primarily characterized by differential settlement. (2) The joints of the lower-layer segments exhibit slight opening, with the opening width relatively small (ranging from 1.00 to 2. 00 mm), which satisfies the waterproof requirements of utility tunnel joints. (3) The foundation subgrade reaction modulus is the most critical factor for enhancing the overall longitudinal stiffness of the structure and controlling local settlement. When the subgrade reaction modulus decreases from 20 000 to 2 500 kN/m3, the maximum settlement of the top slab of the upper-layer utility tunnel increases from 3.53 to 17.03 mm, the maximum differential settlement increases from 1.11 to 6.89 mm, the maximum settlement of the bottom slab of the lower-layer utility tunnel increases from 3.05 to 16.55 mm, and the maximum differential settlement increases from 0.81 to 6.88 mm. (4) Increasing the anchor cable prestress between segments can enhance the overall longitudinal stiffness of the utility tunnel to a certain extent. When the prestress increases from 0 to 230.0 MPa, the maximum settlement at the end of the upper-layer utility tunnel decreases from 5.74 to 4.42 mm, and the differential settlement decreases from 2.05 to 0.71 mm. (5) Increasing the friction coefficient between segments has a relatively minor effect on structural settlement and joint differential settlement. When the friction coefficient increases from 0.5 to 0.8, the maximum settlement decreases from 6.06 to 5.22 mm, and the maximum joint opening decreases from 1.45 to 1.36 mm, indicating a limited contribution to improving the longitudinal stiffness of the utility tunnel.
