高含水率疏浚淤泥新型复合固化材料试验研究

基于传统水泥固化处理方法,提出了水泥-生石灰-高分子添加剂新型复合固化材料处理高含水率疏浚淤泥的新方法,以期快速降低淤泥含水率并提高固化淤泥的无侧限抗压强度,拓展水泥固化淤泥的含水率范围,达到高效廉价固化处理高含水率疏浚淤泥的目的。通过系列室内试验,探讨了该方法处理后高含水率淤泥的无侧限抗压强度变化规律以及各材料掺入比对强度的影响规律。研究结果表明,水泥掺入比低于7%的新型固化材料处理初始含水率2倍液限的高液限淤泥,早期强度大于0.5 MPa,28 d强度大于1 MPa;固化淤泥强度随龄期、水泥和生石灰掺入比的增大而增大;给出了考虑多因素多水平的无侧限抗压强度预测公式,预测值与实测值基本一致。

Solidification of dredged sludge with high water content by new composite additive

The treatment of dredged sludge with high initial water content is very important in geotechnical engineering. Based on the traditional cement-treatment method, a new solidification additive by mixing cement, lime and polymer is proposed, in order to reduce the dredged sludge’s water content and increase unconfined compressive strength rapidly and broaden the water content of cement-treatment method so as to achieve efficient treatment of high water content dredged sludge. A series of laboratory tests have been performed to investigate the variation of unconfined compressive strength and the relationship between material mixing ratio and unconfined compressive strength. The experimental results show that the unconfined compressive strength of solidified sludge increased remarkably by adding cement and lime. The new composite additive could solidify the high liquid limit sludge with initial water content more than 2 times of the liquid limit just with low cement dosage, while its early strength is more than 0.5 MPa, 28 d strength is more than 1 MPa. Finally, a prediction expression of unconfined compressive strength is proposed and verified.