盾构施工参数对地铁穿越公路桥梁桩基的影响

为了提升地铁穿越公路桥梁桩基的稳定性,考察了盾构施工过程中开挖步数、掌子面推力和注浆压力对桩基变形的影响。结果表明,随着开挖步数的增加,桩基横向水平位移与桩身埋深关系曲线逐渐转变为“鼓凸”状,且随着开挖步数增加,桩基横向水平位移呈现逐渐增大的趋势。掌子面推力不会对桩基横向位移造成明显影响,但随着掌子面推力逐渐增大,桩基纵向位移呈现逐渐增大的趋势;随着注浆压力增加,桩体横向位移逐渐增大而纵向位移逐渐减小。在对地铁穿越公路桥梁桩基进行盾构施工过程中,可以通过调整注浆压力来对桩体变形进行控制,从而最大限度的保证桩体的稳定。

Influence of Shield Construction Parameters on Pile Foundation of Subway Crossing Highway Bridge

In order to improve the stability of pile foundation of subway crossing highway bridge,the influence of excavation steps,face thrust and grouting pressure on pile foundation deformation during shield construction was investigated.The results show that with the increase of excavation steps,the curve of the relationship between the horizontal displacement of pile foundation and the buried depth of pile body gradually changes into a"bulge"shape,and with the increase of excavation steps,the lateral horizontal displacement of pile foundation gradually increases.The results show that the lateral displacement of pile foundation will not be affected by the thrust of tunnel face,but the longitudinal displacement of pile will increase gradually with the increase of thrust;the lateral displacement of pile will increase gradually and the longitudinal displacement will decrease with the increase of grouting pressure.In the process of shield construction of subway crossing highway bridge pile foundation,the pile deformation can be controlled by adjusting the grouting pressure,so as to ensure the stability of the pile to the maximum extent.