固化疏浚淤泥作路基材料工程特性试验研究

Experimental analysis of engineering properties of solidified sludge as roadbed filling material

为了探讨粉煤灰和工业矿粉固化疏浚淤泥作路基材料的可行性,通过一系列室内实验研究了不同固化剂配比对固化淤泥击实特性、水稳定性、承载力和抗剪强度的影响。实验结果表明,不同固化剂配比下固化淤泥的最大干密度均超过1.50g/cm3,最优含水率约为20~21%;淤泥固化处理后浸水4d的膨胀率均不超过1.1%,水稳性大幅提升;矿粉含量越高,粉煤灰含量越低,CBR(California Bearing Ratio)值越高,土样的承载力越高,抗剪强度也越高。不同工况浸水4d的CBR值均达到了较高的水平,工况SD10FA20MP(淤泥∶粉煤灰∶矿粉=7∶1∶2)CBR值最高,达到了34.8%,是规范中高速、一级公路路基填料要求最低CBR值的4.35倍,作路基填料使用可行。

To discuss the feasibility of using the fly ash and industrial slag solidified dredged sluge as roadbed material, a series of laboratory tests were performed to investigate the effect of curing agent ratios on the compaction properties, water stability, bearing capacity and shear strength. The test results showed that the maximum dry density of the solidified sludge with different curing agent ratios are higher than 1.50 g/ cms, and the optimum moisture content are about 20~ ~ 21 ~. The soaking induced expansion rate with the soaking time of 4 days are less than 1. 1%, which indicates the water stability are ameliorated after solidification. With the decrease of fly ash and the increase of mineral powder, the CBR（California bearing ratio） and the shear strength are greatly increased. The solidified sludge with different curing agent ratioshave high CBR after soaking for 4 days. The sample of SD10FA20MP has the highest CBR （34.8）, which is 4.35 times of lowest requirement of roadbed filling of highway. It is concluded that it is feasible to use the fly ash and industrial slag solidified dredged sludge as roadbed filling material.