桩侧泥皮和桩底沉渣对钻孔桩承载力影响的数值模拟

运用有限元软件模拟分析了桩侧泥皮和桩底沉渣对钻孔桩承载力的影响。通过对不同桩底沉渣厚度和强度下单桩承载力模拟计算，研究了沉渣对钻孔桩承载力的影响规律，指出沉渣厚度的影响存在临界值，当沉渣厚度超过临界值300mm时沉渣厚度对单桩承载力影响不是很明显，主要是沉渣强度的影响。引入桩侧泥皮摩阻力折减系数来考虑泥皮强度的影响，计算分析了泥皮高度和强度对钻孔桩承载力的影响，并指出泥皮高度是主要因素。

Numerical simulation of effects of mud cake and bottom sediment on bearing capacity of bored pile

The effects of shaft mud cake and bottom sediment on beating capacity of bored pile are simulated by using FEM software Based on the calculated results of single pile beating capacity under the conditions of different thicknesses and elastic moduli of bottom sediment, the effect rule of sediment on beating capacity of bored pile is studied. The calculated results show that the effect of thickness of bottom sediment on beating capacity is threshold and no more obvious than the elastic modulus when the thickness of sediment is over 300 mm.The effects of height and strength of mud cake on bearing capacity of bored pile are calculated by considering the effect of mud cake strength taken place of shaft friction deduction coefficient of shaft mud cake; and the results show that the main effect factor of mud cake on bearing capacity of bored pile is height of mud cake around pile shaft.