胶结材料对云南红土胶结特性的影响研究

以云南典型红土作为基本土料,分别以石灰、粉煤灰两种固态土壤强固剂和路邦土壤强固剂一种液态土壤强固剂及其组合作为胶结材料,通过击实试验和直剪试验对比研究不同胶结材料对红土最佳击实特性及胶结强度的影响。试验结果表明,胶结材料的加入降低了红土的最大干密度,固态土壤强固剂的加入使红土的最优含水率降低,液态土壤强固剂的加入使红土的最优含水率提高;红土中加入不同种类的胶结材料都可以使红土产生胶结强度,其胶结强度随垂直压力的增大而增大,但增大程度随垂直压力的增大而降低;其胶结效果取决于胶结材料的种类、加入比例以及静置时间等因素,一般地,组合胶结材料的胶结效果优于单一胶结材料的胶结效果,液态土壤强固剂的胶结效果优于固态土壤强固剂的胶结效果;其胶结效果的实质在于增强了红土颗粒之间的连接力和摩擦力,尤其是大幅度地提高了颗粒之间的连接力,使红土的整体稳定性增强,承载能力提高,工程性能改善。

Effects of cementatory materials on Yunnan laterite

The functions of the cementatory materials on laterite were studied by means of the comparison tests of compaction and direct shear in which the typical laterite in Yunnan province.The soil was mixed with two kinds of materials reinforcing agent,lime,powder ash from stove or liquid roadbond soil reinforcing agent or their combinations.The results indicate that the maximum dry density of laterite will be reduced if cementatory materials and the optimum water content are used,that it will decrease if solid agent is used,and that it will increase if liquid agent is used.The cementatory effect will take place in laterite if the materials that it depends on the static placing time gap,the type and amount of materials are used,and it will be improved when the vertical pressure increases,in which the improvement will be reduced along with the increasing of the vertical pressure.Generally,the cementatory effects of combined materials are better than single one,the liquid agent is better than solid one.The essential fact of the cementatory functions is that the cementatory materials increase the conjunction and friction among particles of laterite,in which especially the conjunctions among the particles are significantly increased.Therefore the engineering properties of the laterite is improved,and the laterite is more stable and stronger.