【摘要】 针对浅埋超大断面矩形顶管顶进引起的环境影响效应，以深圳市某拟建顶管法地铁车站为背景，建立了顶管施工全过程三维有限元数值模型，研究了浅埋超大断面矩形顶管施工的背土效应及其对上方既有箱涵的影响。结果表明：顶管下穿箱涵前，箱涵的不均匀沉降增长缓慢，箱涵迎土面所受土压力不断增大；顶管下穿箱涵时，箱涵的不均匀沉降量急剧增大，箱涵迎土面所受土压力逐渐降低；顶管穿出箱涵后，箱涵的不均匀沉降量和迎土面所受土压力均先下降而后趋于稳定。浅埋超大断面矩形顶管施工的背土效应使得箱涵的最大水平位移大于最大竖向位移，实际工程中应采取措施减少背土效应的影响。更多还原

【Abstract】 A three-dimensional finite element model capable of simulating the whole construction process of a shallow-buried large-section rectangular pipe jacking is established to research the environmental effect.Based on the engineering background of a pipe-jacking underground subway station to be built in Shenzhen, the carrying-soil effect of the shallow-buried large-section rectangular pipe jacking construction and its influence on the existing box culvert are studied.The results show that the uneven settlement of the culvert grows slowly and the soil pressure on the front surface of the culvert constantly increase before the pipe jacking passes through the culvert.When the pipe jacking passes through the culvert, the uneven settlement of the culvert increases sharply and the earth pressure on the front surface of the culvert gradually decreases.After the pipe jacking passes through the culvert, both the uneven settlement of the culvert and the earth pressure on the front surface of the culvert first decreases and then stabilizes.The carrying-soil effect of shallow buried large-section rectangular pipe jacking makes the maximum horizontal displacement of the culvert greater than the maximum vertical displacement.In practical engineering, measures should be taken to reduce the influence of carrying-soil effect.更多还原