碎石桩设计参数对复合地基抗液化性能的影响

对碎石桩复合地基进行完全耦合的三维有效应力动力分析，探讨了碎石桩桩径、桩长和桩间距等设计参数对碎石桩复合地基抗液化性能的影响。结果表明，浅层范围内桩长对孔压比的影响较小，随深度的增大，桩长的影响有增大的趋势；在其他条件不变的情况下，随桩径的增大，桩间土中的超孔隙水压力降低，桩径对超孔压发展的影响沿深度方向不同，主要表现在中下部；当仅改变桩间距时，随桩间距的增大，桩间土中的超孔压升高，在工程设计时，桩径与桩间距的比值宜大于0.27，即桩间距的设计值不宜超过3.75D（D为碎石桩桩径）；随碎石桩本身渗透系数的增加，复合地基中不同深度处的超孔压都有所降低，并且随深度的增大，这种影响有增大的趋势。

Influence of stone columns design parameters on anti-liquefaction nature of composite foundation

Stone columns composite foundation is analyzed by the developed fully coupled three-dimension effective-stress dynamic analysis procedure; the influence of stone columns design parameter on anti-liquefaction nature of composite foundation is discussed. The research shows that the influence of column length is minor in superficial layer and is major in deep level; under other condition fixed, with the diameter of stone columns increasing, the excess pore water pressure decreases; with the spacing of columns increasing, the excess pore water pressure increases. In engineering design, the ratio of the diameter and spacing of columns should be bigger than 0.27, or the spacing of columns is smaller than 3.75D; with the permeability of stone columns increasing, the excess pore water pressure in different depths decreases; and the influence is stronger with the depth increasing.