摘要：To improve the strength of granite residual soil and minish the influence of coastal sludge on the environment.In this paper,the effectiveness of coastal sludge in the improvement of granite residual soil was investigated,and the contrast tests of unconfined compression (UC) were performed on two groups of granite residual soil mixed with flyash and calcium lime.And the microstructures of the treated specimens were analyzed via scanning electron microscopy (SEM).The results obtained show that the unconfined compressive strength (UCS) of the GRCS specimens firstly increase and then decrease with the ameliorant content increasing regardless of water content and curing time.The efficiency of coastal sludge to improve the strength of granite residual soil is optimistic,at least relative to fly ash.The maximum increment of the long-term UCS is found in GRCS specimen (20% ameliorant content and 20% water content).Once the water content changing from 10%to 20%,AUCs of GRCS specimens in- crease obviously.The inclusion of ameliorant powder conductively improves the particle gradation of granite residual soil,which results in the structures more compact and thus a relatively higher strength of the improved samples especially for GRCS samples.The way of coastal sludge heightening the strength of granite residual soil is not the result of hydration reaction,but relies on the viscosity of clay minerals.
关键词：Strength development;Granite residual soil;Coastal sludge;Microstructure;Scanning electron microscope
