摘要：
High-piled wharf is widely used in port construction in the southwest region of China. The pile foundation pile is liable to be deformed horizontally after pile back filling, especially in the case of deep backfill pile deformation, which is more serious, thus affecting the normal use of foundation piles and even security and stability. Based on the model test of the slope foundation pile, a pile-soil refinement numerical analysis model for the deep filling slope pile is established to study the effects of the filling thickness, internal friction angle, pile cross-section size and other design parameters on the internal force and deformation in the deep filling slope. Research shows: with the increase of the backfill depth, the displacement distribution of the pile gradually changes from straight to S, and the maximum displacement of the pile gradually moves down from the pile top to the backfill, and the pile body force is increaseing with the thicknes of backfill. When the shear strength of the backfill material is increased little by little, the pile body deformation can be effectively controlled. However, when the shear strength of the backfill is increased to a certain extent, the displacement of the pile remains basically unchanged. Increasing the shear strength of backfill material has a limited effect on controlling the deformation of pile. When the support pile diameter is small, the pile body has S-shaped deformation, thus increasing the pile diameter and decreasing the pile bending deformation, but excessive use of large-diameter pile may cause the pile to produce a large displacement. The paper puts forward a h-type double-pile optimal support scheme, which provides technical support for the design and construction of the pile foundation of the inland port.%高桩码头在我国西南地区港口建设中应用愈来愈广泛,码头基桩受桩后回填土作用容易发生水平变形,尤其是在深厚回填土情况下基桩变形更加严重,影响基桩的正常使用甚至安全稳定.结合斜坡基桩室内模型试验,通过建立深填斜坡中桩-土精细化数值分析模型,研究深填斜坡中回填土厚度及内摩擦角、桩截面尺寸等设计参数对基桩内力、变形的影响.研究表明:随着回填深度的增加,桩身位移分布由直线型逐渐变为S型,桩身最大位移由桩顶逐渐下移至回填区,回填土厚度越大,桩身受力越大.当回填土材料的抗剪强度逐步提高时,能有效控制桩身变形,但当回填土抗剪强度提高到一定值后,桩顶位移基本保持不变,提高回填土抗剪强度对控制桩身变形的作用有限.支护桩径较小时,桩身呈S型变形,增大桩径,桩身弯曲变形减小,但过分使用大直径基桩反而使桩顶产生较大位移.同时提出了深填斜坡h型双桩优化支护方案,为内河港口码头桩基设计建造提供技术支撑.
