基桩弹性模量对组合桩复合地基桩土荷载分担比的影响

Influence of elastic modulus of piles on share load ratio between pile and soil of combination-pile composite foundation

在分析桩土相互作用的基础上,将柔性桩和天然地基形成的复合地基当作刚性桩的等效天然地基,考虑垫层效应,推导了复合地基在弹性工作阶段桩土的荷载分担比及沉降的解析解,利用解析解编制程序分析长、短桩弹性模量对桩土荷载分担比的影响。分析表明,随长桩弹性模量的增大,长桩的荷载分担比增大,短桩及桩间土的荷载分担比减小,但长桩的弹性模量大于28 000MPa时,其对桩土的荷载分担比影响较小;随短桩弹性模量的增大,长桩的荷载分担比减小,短桩及桩间土的荷载分担比增大。

Regarding the combination-pile composite foundation made up of soft piles and nature soil as the substitute soil among rigid piles and considering cushion effect at the same time,share load ratio and settlement resolution of combination-pile composite foundation were deduced.Then the effect of modulus of piles on the share load ratio is analyzed.It is indicated that the share load of long-pile increases and the share load of cushion and short-pile decreases with the elastic modulus of long-pile increasing.But the influence on share load ratio diminished when the elastic modulus of long-pile is greater than（28 000MPa.） The pattern of the short-pile and the soil foundation are contrary to the long-pile in the same conditions.