多孔大断面矩形顶管施工的地层变形特征及演化规律
Stratum deformation characteristics and evolution laws induced by porous large section rectangular pipe jacking construction

基于随机介质理论，计算多孔矩形顶管隧道施工引起的地层变形，通过实际工程验证计算结果的可靠性，分别讨论单个及多孔大断面矩形隧道施工条件下地层的水平位移、倾斜、曲率以及水平变形的演化规律。研究结果表明：沉降范围和沉降累计最大值均呈线性增大，沉降累计最大值的增幅较大，且4孔时均为单孔的2倍；各地层变形累计最大值均在3号顶管中心附近变化最大，水平位移和倾斜累计值均先增加后减小，变形和曲率累计值均呈线性减小；各相邻顶管中间的扰动区域重叠所产生的扰动效应随管节间距和尺寸的变化而变化。
Based on stochastic medium theory, the deformation of the strata caused by the construction of porous rectangular tunnel is calculated, and then through the actual project to verify the reliability of the method, the settlement characteristics of strata under the construction condition of single large section rectangular tunnel and the evolution of horizontal displacement, inclination, bending and horizontal deformation of the strata under the construction of porous tunnel are discussed respectively. The results show that the settlement range and settlement cumulative maximum all show a linear increase, the cumulative maximum value of settlement increases greatly ,and the maximum value at four is two times of single; The accumulative maximum values of deformation in each layer changes the most near the No.3 pipe jacking center, horizontal displacement and tilt cumulative values are increased first and then decreased, deformation and curvature cumulative values are linearly reduced; The disturbance produced by the overlapped disturbance region in each adjacent pipe jacking varies with the pitch and size of the pipe section