考虑土体应力历史影响的沉降修正初探

Discussion of settlement modification considering stress history of soil mass

在分层总和法中,e-lgp法比av法、e-p法优越之处在于其考虑了土体应力历史的影响,但由于参数的难以确定,导致e-lgp法在实际工程中很少应用。介绍了一种在无高压固结试验时可使av法、e-p法中计入土体应力历史影响的思路,提出了相应的修正系数概念,分析了该修正系数对于不同状态土体的大致取值范围,并给出了其近似计算式。实例验证表明,av法、e-p法经修正后结果更趋于合理,且与e-lgp法很接近,故在工程实践中具有一定的参考价值。

In layerwise summation method, e-lgp is superior to av and e-p method; the reason is that it can be in consideration of the influence of soil stress history. But it is a pity that e-lgp method is rarely used in practical engineering because the related parameters are difficult to be determined. One thought to consider the influences of soil stress history in av and e-p method is given when lack of high pressure consolidation test data; and the corresponding concept of correction coefficient Ms is put forward. Besides, the approximate spans of Ms for different status soils are analyzed. Then, the calculated formula is developed. It is found that the results of av and e-p methods which are rectified with the correction coefficient are more accuracy and more closed to the e-lgp method. This method can be reference for engineers.