鲁西黄河冲积土次固结特性试验研究

Experimental Study on Secondary Consolidation Characteristics of the Yellow River Alluvial Soil in Western Shandong

以黄河冲积土为研究对象,通过三组一维次固结变形试验研究其次固结特性,即相同加载比正常固结、超载预压固结和不同加载比正常固结三组试验。分析发现:黄河冲积土的次固结系数与固结压力大小相关,离散性大,均值较其他地区小;受超载预压的土,其次固结特性受影响较大,次固结系数减小;相同加载比的压实黄河冲积土,次固结系数与压缩指数之间存在较好的线性关系。三组试验的lnP/lnC_a与lnP之间都有很好的直线关系,拟合出了相关公式;并给出了常数A、B的取值推荐方法。给出了次固结系数C_a的取值建议。利用经验公式和实际沉降值进行比较,验证了理论的正确性。

Taken the Yellow River alluvial soil as the research object,and through three groups of one-dimensional consolidation deformation tests,normal consolidation,surcharge preloading consolidation with the same proportional loading and normal consolidation with different proportional loading were carried out.The analysis found that the secondary consolidation coefficient of the Yellow River alluvial soil was related to the size of consolidation pressure,the data was very discrete,and the mean value was smaller than that in other areas;The secondary consolidation characteristics were greatly influenced by the overloading preloading soil,and the secondary consolidation coefficient decreased;There was a good linear relationship between the secondary consolidation coefficient and the compression index of the compacted Yellow River alluvial soil with the same proportional loading;There was a good linear relationship between ln P/ln C a and ln P.The correlation formula was fitted,and the method of recommending the value of constant A and B was also given;The suggestions for the value of the secondary consolidation coefficient C a were given,and to verify the correctness of the theory,the empirical formula was compared with the actual settlement value.