经典Terzaghi固结理论模型通常仅考虑外荷载变化引起的土体固结,而没有考虑工程中真空井点降水、回灌等问题引出的局部源汇对土体固结过程的影响。为此在Terzaghi模型基础上,采用一阶导数的不连续性引入局部源汇条件,然后按分离变量法导出了存在局部源汇的Terzaghi固结解析解。结合算例简要分析了定常源汇情况下双面排水地基中超静孔压的分布规律,以及局部源汇引起的固结度与传统的荷载引起的固结度的差异规律。结果表明:源汇点埋深、源汇强度和土层固结系数对负超静孔压的发展规律具有重要影响;超静孔压的空间分布形态以源汇点为界分为上下两段曲线。此可用于分析工程中源汇问题引起的地层沉降或抬升等工况。
The traditional Terzaghi's consolidation theory model usually considers the consolidation process caused only by surcharge, ignoring the effect of source/sink term which occurs during vacuum well dewatering and artificial ground water recharge, etc. Based on the Terzaghi's model and introducing discontinuous first derivative to take account of local source/sink term, the analytical solution to Terzaghi's source/sink-caused consolidation is put forward using the method of variable separation. Through a case study, the excess pore pressure distribution in soil foundation is studied under the condition of double-drainage and constant source/sink. A comparison is made to analyze the difference between the degrees of consolidation produced respectively by source/sink and surcharge. The results show that the location and the intensity of local source/sink, and coefficient of consolidation play a major role in the development of the excess pore pressure; the distribution curve of the excess pore pressure is characterized by the upper and lower segments divided by source/sink location. The proposed solution can be applied to such source/sink-induced engineering practice as ground settlement and upheaval, etc.