改良高液限黏土水稳定性试验研究

针对高液限黏土路基填料在多雨气候下可能出现的耐久性问题，本研究以在建龙浦高速公路分布的高液限红黏土为试验对象，开展室内试验研究了浙江高液限黏土以及石灰和水泥改良土的水稳定性。通过普通浸水试验和干湿循环试验，以无侧限抗压强度与CBR为主要研究指标进行研究。湿化试验发现在压实条件下，高液限黏土初始饱和度越高，湿化速度越慢，破坏性越小，水稳定性越强。浸水高液限黏土与改良土的无侧限抗压强度和CBR值大多都随泡水时间的增加而衰减，而在一定时间内4%的石灰改良土浸水CBR随时间的增加而提高。干湿循环作用下，素高液限黏土CBR值小范围的先增大后减小。较高掺量的石灰或水泥改良高液限土在干湿循环作用下，无侧限抗压强度几乎不变或衰减较小，并且在多次循环后保持较高强度。

Experimental Study on Water Stability of Improved High Liquid Limit Clay

According to the possible durability problem of high liguid limit clay as roadbed filling in rainy climate, a series of tests on water stability characteristics of pure high liquid limit soil and lime or cement improved soil were carried out.The pure soils was red clay which picked from under-construction Longquan-Pucheng Highway section. The tests focused on the unconfined compression strength and CBR under ordinary water immersion and drying-wetting cycle condition. Exprimetal results indicated that compacted high liquid limit clay with higher initial saturation had lower humidification speed , destructed slowlier, and had higher water stability. The unconfined compression strength and CBR of most pure high liquid limit clay and improved soils decreased with the increase of soaking duration. But CBR value of 4% lime-improved soils with water immersion increased within a porid. During drying-wetting cycles, the CBR value of the high liquid limit clay increased first and then decreased. The unconfined compression strength of improved high liquid limit soils improved with high dosage of lime or cement kept unchanged or decreased slightly and the soil still kept a high strength after multiple cycles.