The disintegration of granite residual soil is especially affected by variations in physical and chemical properties. Serious geologic hazards or engineering problems are closely related to the disintegration of granite residual soil in certain areas. Research on the mechanical properties and controlling mechanisms of disintegration has become a hot issue in practical engineering. In this paper, the disintegration characteristics of improved granite residual soil are studied by using a wet and dry cycle disintegration instrument, and the improvement mechanism is analyzed. The results show that the disintegration amounts and disintegration ratios of soil samples treated with different curing agents are obviously different. The disintegration process of improved granite residual soil can be roughly divided into 5 stages: the forcible water intrusion stage, microcrack and fissure development stage, curing and strengthening stage, stable stage, and sudden disintegration stage. The disintegration of granite residual soil is caused by the weakening of the cementation between soil particles under the action of water. When the disintegration force is greater than the anti-disintegration force of soil, the soil will disintegrate. Cement and lime mainly rely on ion exchange agglomeration, the inclusion effect of curing agents on soil particles, the hard coagulation reaction and carbonation to strengthen granite residual soil. Kaolinite mainly depends on the reversibility of its own cementation to improve and strengthen granite residual soil. The reversibility of kaolinite cementation is verified by investigating pure kaolinite with a tensile, soaking, drying and tensile test cycle. Research on the disintegration characteristics and disintegration mechanism of improved granite residual soil is of certain reference value for soil modification.

花岗岩残土的崩解尤其受物理和化学性质变化的影响。严重的地质灾害或工程问题与某些地区花岗岩残土的崩解密切相关。解体力学性能及其控制机制的研究已成为实际工程中的热点问题。本文利用干湿循环崩解仪研究了改良花岗岩残土的崩解特性，分析了改良机理。结果表明，不同固化剂处理的土样的崩解量和崩解率存在明显差异。改良花岗岩残土的崩解过程大致可分为5个阶段：强制进水阶段、微裂纹和裂隙发展阶段、固化强化阶段、稳定阶段和突然崩解阶段。花岗岩残土的崩解是由于土壤颗粒之间的胶结作用在水的作用下减弱而引起的。当解体力大于土壤的抗解体力时，土壤就会解体。水泥和石灰主要依靠离子交换团聚、固化剂对土壤颗粒的包合作用、硬混反应和碳化作用来强化花岗岩残土。高岭石主要依靠自身胶结的可逆性来改善和强化花岗岩残土。高岭石胶结的可逆性通过对纯高岭石进行拉伸、浸泡、干燥和拉伸试验循环。研究改良花岗岩残土的崩解特性及崩解机理，对土壤改良具有一定的参考价值。