排水固结下卧层固结度简化计算

提出竖井未打穿软土地基下卧层固结度简化计算方法。将竖井地基划分为竖井打设区和下卧层两个部分,竖井打设区采用轴对称固结理论,而下卧层采用太沙基一维固结理论,两部分在渗透面上满足孔压连续条件。对一算例分别采用简化方法、精确解法及已有近似解法进行了固结分析,表明简化方法与精确解法结果较为接近,满足工程精度。由于该解答为显式解,工程应用较为方便。

Simplified Consolidation Calculation on Substratum of Ground Improved by Drainage Consolidation

A simplified method for consolidation analysis on soft clay foundation with partially penetrated vertical drains under instantaneous preloading is developed.The unit cell of vertical drain is divided into two parts: the vertical drain driving section and substratum section.The vertical drain driving section is analyzed by symmetrical consolidation theory and the substratum section is analyzed by Terzaghi's 1-D consolidation theory. Pore pressure continuity is used to relate the two sections.To evaluate the precision of the approximate analytical solution,one case under surcharge preloading is analyzed using the simplified solution and existing semi-analytical solution respectively.It is shown that the result by the simplified solution is approximate to that obtained from the semi-analytical solution,satisfying the engineering precision.The simplified method is convenient to be used in engineering because the solution expression is explicit.