锚杆对双排桩结构变形和受力影响分析

Analysis of effect of anchor on deformation and force of double-row piles

采用适用于敏感环境下基坑数值分析的硬化类弹塑性本构模型,针对锚杆对双排桩变形和受力的影响进行数值模拟。分析表明:锚固角度的增加能有效减小双排桩的最大水平位移和后排桩的桩身控制弯矩,但减小幅度随锚固角度增大而减小;在实际设计中,在周边环境允许的条件下,应尽可能增加锚杆与后排桩的夹角。锚固力的增加对双排桩结构的变形控制作用明显,能显著降低桩身最大水平位移,减小幅度也随锚固力的增加而减小;锚固力较大时会增大桩的控制弯矩,使桩的截面或配筋增加;在实际设计中,锚固力不应过大,可随信息化施工对基坑变形进行主动控制。

Using the strain hardening elastoplastic constitutive model which is suitable for numerical analysis of deep excavations in close proximity to sensitive properties, the effect of the anchor on deformation and force of double-row piles is discussed. Increasing the anchorage angles can effectively reduce not only the maximum horizontal displacement of double-row piles but also the bending moments of the back row piles. Increasing the anchorage forces can only effectively reduce the maximum horizontal displacement of double-row piles. The bending moments increase when the anchorage force is larger. In the actual design, we should choose the possible larger angle between anchor and the back row piles and actively control the anchorage forces along with the monitoring.