【摘要】 以浙江衢州至丽水铁路箱式路基工程为研究对象，采用三维数值模拟方法建立了列车荷载-有砟轨道-箱式路基-复合地基耦合模型，对体系在不同荷载作用下的地基沉降、箱体位移、箱体应力及土压力等进行分析。结果表明，基底垫层沉降量大于CFG桩，双线荷载下累计沉降分别为0.86 mm和0.55 mm;顶板和底板横向测线的挠曲变形分别呈“M”和“W”型变形，顶板纵向中心和两边缘测线的挠曲变形在列车荷载作用下分别呈下凹和上凸状，腹板水平位移对称分布；双线列车荷载作用下，箱体最大竖向压应力和拉应力、最大水平压应力和拉应力及最大剪应力分别为0.560 MPa和0.086 MPa、0.470 MPa和0.450 MPa及-0.210 MPa;桩帽区域土压力应力集中显著，基底与桩顶土压力分布呈反向特征。更多还原

【Abstract】 Taking the Quzhou-Lishui Railway in Zhejiang Province as the case study, a coupled model of train load, ballasted track, box-type subgrade, and composite foundation was established using numerical simulation. The ground settlement, box displacement, box stress and earth pressure of the system under different loads were analyzed. The results indicate that the settlement of the base cushion is greater than that of the CFG piles, with cumulative settlements under double-track loads of 0.86 mm and 0.55 mm, respectively. The deflection deformations along the transverse measuring lines on the top slab and bottom slab exhibit an “M” and “W” patterns, respectively. Under train loads, the deflection deformations along the longitudinal centerline and the two edge lines of the top slab are concave and convex, respectively, while the horizontal displacements of the webs are symmetrically distributed. Under double-track train loads, the maximum vertical compressive stress, vertical tensile stress, maximum horizontal compressive stress, horizontal tensile stress, and maximum shear stress in the box are 0.560 MPa and 0.086 MPa, 0.470 MPa and 0.450 MPa, and-0.210 MPa, respectively. Significant stress concentration of earth pressure is observed in the pile cap area, and the distribution of earth pressure on the base cushion and at the pile tops exhibits an inverse characteristic.更多还原