岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2013年
10期
2991-2996,3010
,共7页
软土%非线性%大变形%一维固结%指数形式渗流定律
軟土%非線性%大變形%一維固結%指數形式滲流定律
연토%비선성%대변형%일유고결%지수형식삼류정률
soft clay%nonlinearity%large strain%1D consolidation%exponential flow law
考虑土中指数形式渗流定律以及土体的非线性固结特性,以超静孔隙水压力为变量在拉格朗日坐标系内建立了软土一维大变形固结问题的控制方程及其求解条件,并运用有限差分法获取其数值解答。在指数形式渗流定律退化为达西定律下,通过将差分解与已有的半解析解进行对比,验证了数值计算的可靠性。最后对指数形式渗流定律下软土一维非线性大变形固结性状进行计算分析,结果表明:m<1时,软土的非线性大变形固结速率会随外载增大而减慢;m>1时,软土的非线性大变形固结速率会随着外荷载的增加而加快;软土非线性大变形固结速率要比非线性小变形固结速率快,且差别会随荷载增大而加剧;此外,大变形固结理论的最终沉降值要小于小变形固结理论,且差别会随着荷载的增大而加剧。
攷慮土中指數形式滲流定律以及土體的非線性固結特性,以超靜孔隙水壓力為變量在拉格朗日坐標繫內建立瞭軟土一維大變形固結問題的控製方程及其求解條件,併運用有限差分法穫取其數值解答。在指數形式滲流定律退化為達西定律下,通過將差分解與已有的半解析解進行對比,驗證瞭數值計算的可靠性。最後對指數形式滲流定律下軟土一維非線性大變形固結性狀進行計算分析,結果錶明:m<1時,軟土的非線性大變形固結速率會隨外載增大而減慢;m>1時,軟土的非線性大變形固結速率會隨著外荷載的增加而加快;軟土非線性大變形固結速率要比非線性小變形固結速率快,且差彆會隨荷載增大而加劇;此外,大變形固結理論的最終沉降值要小于小變形固結理論,且差彆會隨著荷載的增大而加劇。
고필토중지수형식삼류정률이급토체적비선성고결특성,이초정공극수압력위변량재랍격랑일좌표계내건립료연토일유대변형고결문제적공제방정급기구해조건,병운용유한차분법획취기수치해답。재지수형식삼류정률퇴화위체서정률하,통과장차분해여이유적반해석해진행대비,험증료수치계산적가고성。최후대지수형식삼류정률하연토일유비선성대변형고결성상진행계산분석,결과표명:m<1시,연토적비선성대변형고결속솔회수외재증대이감만;m>1시,연토적비선성대변형고결속솔회수착외하재적증가이가쾌;연토비선성대변형고결속솔요비비선성소변형고결속솔쾌,차차별회수하재증대이가극;차외,대변형고결이론적최종침강치요소우소변형고결이론,차차별회수착하재적증대이가극。
Considering the exponential seepage flow law in soil and the nonlinear consolidation behavior of soil, the equations and solution conditions governing 1D nonlinear large-strain consolidation, in which the excess pore water pressure served as variable, were founded in Lagrangian coordinates;and its numerical solutions were obtained by finite difference method. On condition that the exponential seepage flow law was degenerated into Darcy’s law;the reliability of numerical solutions was testified by comparing the finite difference solutions to semi-analytical solutions. Finally, the consolidation behavior of 1-D non-linear large strain consolidation with exponential flow law were analyzed;and the results show that the rate of nonlinear large strain consolidation of soft clay slows down with increasing the external load in case of m<1, and accelerates with increasing the external load in case of m>1. The rate of nonlinear large strain consolidation is faster than that of nonlinear small strain consolidation;and the difference between them may intensify with increasing the external load. Furthermore, the final settlement by the theory of large strain consolidation is smaller than that of small strain consolidation, and the difference between them also may intensify with increasing the external load.