西安建筑科技大学学报(自然科学版)

考虑桩土模量比随固结而不断变化、地基既存在径向渗流也存在竖向渗流,得到了碎石桩复合地基的非线性固结解析解.通过对解的分析表明:与传统理论不同,在桩土模量比变化的条件下,当渗透指数等于压缩指数时(即Cc/Ck=1),复合地基非线性固结解与线性固结解不一致; 与已有的考虑桩土模量比不变条件下的解相比,本文理论求得的地基固结度要小,也就是说,忽略复合地基固结过程中桩土模量比的变化,会使计算固结度偏大,是偏于危险的.

Considering that the modulus ratio of pile to soil varies with consolidation and the foundation has both radial seepage and vertical seepage, the nonlinear consolidation analytical solution of gravel pile composite foundation is obtained. The analysis of the solution shows that, under the condition of changing pile-soil modulus ratio, the nonlinear consolidation solution of composite foundation is inconsistent with the linear consolidation solution when the permeability index is equal to the compression index(i.e Cc/Ck=1), which is different from the traditional theory; compared with the existing solution under the condition of constant pile-soil modulus ratio, the consolidation degree obtained by the theory in this paper is smaller, that is to say, ignoring the change of pile-soil modulus ratio in the process of consolidation of composite foundation will cause the calculated consolidation degree to be larger, which is dangerous.

引言
1 固结方程及求解条件
2 固结方程求解
3 解的讨论
4 结论

图1 复合地基固结示意图<br/>Fig.1 Schematic diagram of consolidation of composite foundation

图1 复合地基固结示意图
Fig.1 Schematic diagram of consolidation of composite foundation

图2 土体孔隙比随有效应力变化曲线<br/>Fig.2 Curve of soil porosity ratio varying with effective stress

图2 土体孔隙比随有效应力变化曲线
Fig.2 Curve of soil porosity ratio varying with effective stress

图3 土体渗透性与孔隙比关系曲线<br/>Fig.3 The relation curve of soil permeability and pore ratio

图3 土体渗透性与孔隙比关系曲线
Fig.3 The relation curve of soil permeability and pore ratio

图4 涂抹区水平渗透系数<br/>Fig.4 Horizontal permeability coefficient of smear area

图4 涂抹区水平渗透系数
Fig.4 Horizontal permeability coefficient of smear area

图5 不同桩土模量比时本文解与线性固结解的比较<br/>Fig.5 Comparisons between the present solution and the linear consolidation solution for different modulus ratios of pile to soil

图5 不同桩土模量比时本文解与线性固结解的比较
Fig.5 Comparisons between the present solution and the linear consolidation solution for different modulus ratios of pile to soil

图6 不同荷载初始应力比时本文解与线性固结解的比较<br/>Fig.6 Comparisons between the present solution and the linear consolidation solution for different ratios of load to initial stress

图6 不同荷载初始应力比时本文解与线性固结解的比较
Fig.6 Comparisons between the present solution and the linear consolidation solution for different ratios of load to initial stress

图7 本文解与考虑桩土模量比不变情况下解的对比<br/>Fig.7 Comparison between the solution in this paper and that considering the invariable modulus ratio of pile to soil

图7 本文解与考虑桩土模量比不变情况下解的对比
Fig.7 Comparison between the solution in this paper and that considering the invariable modulus ratio of pile to soil

图8 竖向渗流对固结度的影响<br/>Fig.8 The effect of vertical seepage on the degree of consolidation

图8 竖向渗流对固结度的影响
Fig.8 The effect of vertical seepage on the degree of consolidation

图9 扰动区水平渗透系数模式对固结度的影响<br/>Fig.9 Influence of horizontal permeability coefficient model in disturbed zone on consolidation degree

图9 扰动区水平渗透系数模式对固结度的影响
Fig.9 Influence of horizontal permeability coefficient model in disturbed zone on consolidation degree

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备注

引言

1 固结方程及求解条件

2 固结方程求解

3 解的讨论

4 结论

期刊信息