基于微观结构变化的水泥改良花岗岩残积土的击实特性OA

To investigate the effects of cement content on the compaction characteristics and microstruc-tural evolution of granite residual soil,this study used granite residual soil from Yiyang,Hunan Prov-ince,and conducted compaction tests,scanning electron microscopy(SEM)image analysis,and energy dispersive spectrometer(EDS)spectroscopy with cement contents of 0%,3%,5%,7%,and 9%.The ex-periments revealed that the modifying effect of cement does not continue to increase as the cement con-tent rises.Microscopic tests further revealed the underlying mechanisms within the soil.SEM observa-tions showed that as the hydration reaction progressed,the microscopic porosity decreased significantly from 14.16%in its natural state to 6.00%;EDS spectroscopy results showed that the mass fraction of Ca in the soil increased significantly from 0%to 10.02%,indicating enhanced cement hydration.The for-mation of hydration products promoted pore filling and led to a redistribution of the elemental composi-tion in the specimens.In engineering practice,it is recommended that the admixture dosage for conven-tional subgrade projects be controlled at around 5%;if higher compaction requirements are needed for specific sections,a dosage of 7%may be selected,but this must be accompanied by strict crack-prevention and curing measures.