越江钢筋混凝土顶管施工三维数值分析

顶管法作为一种非开挖技术,在城市隧道管线的建设和改造中具有广泛应用。然而,顶管施工不可避免地会对周围既有结构物造成一定的影响。为了研究如何规避顶管施工的风险,基于白龙港南线输送干线的过江管工程的W2-W1标段,通过数值模拟的方法研究了顶管施工过程中机头支护压力、注浆模量、摩阻力的变异对地层、桩基变形影响的变化规律,并分析了软土地区复杂条件下顶管施工各施工参数对周围环境影响的敏感性。结果表明:在实际施工过程中,当机头支护压力略小于顶管中心土层自重应力时能有效减小环境影响;同时也需要尽可能减小注浆与顶管之间的摩擦系数,并根据实际目标需求选择注浆模量。

3D Numerical Analysis of Cross-River Reinforced Concrete Pipe-Jacking Construction

As a trenchless technology, pipe-jacking method is widely used in the construction and renovation of urban tunnel pipelines. However, the construction of pipe-jacking will inevitably have a certain impact on the surrounding existing structures. In order to study how to avoid the risk of pipe jacking construction, based on the W2-W1 tenders crossing the river of the South Transport Main Stem of the Bailonggang, the influence of variation of head support pressure, grouting modulus and friction resistance on deformation of strata and pile foundation during pipe jacking construction was studied by numerical simulation and the sensitivity of the construction parameters of the pipe-jacking construction to the surrounding environment under complex conditions in the soft soil area was analyzed. The results show that: in the actual construction process, the head support pressure is slightly less than the self-weight of the soil layer at the pipe jacking center, which can effectively reduce the environmental impact. On the other hand, it"s necessary to reduce the friction coefficient between the grouting and pipe jacking as far as possible and select grouting modulus according to actual target requirements.