冲击荷载作用后吹填土长期性能研究

Experimental study on the growth mechanism of soil strength under impact loading reclamation

以天津滨海旅游区吹填土为试验材料,分别将冲击荷载、排水条件、冲击击数与冲击次数组合作为变量模拟现场冲击荷载作用进行地基处理,并对处理后的土体进行蠕变试验。试验结果表明:土体长期性能受冲击荷载影响明显,且与土体结构有关。当冲击荷载低于吹填土结构屈服应力时,随着冲击荷载的增大,土体蠕变变形逐渐减小,长期强度不断增强;当冲击荷载大于吹填土结构屈服应力时,土体结构大量破坏,长期性能反而减弱。在冲击荷载低于且趋近土体结构屈服应力的条件下,冲击方式和排水条件均对土体长期性能有影响,当冲击能量相同时,随着冲击次数增多,土颗粒间连结作用增强,结构更加密实,长期性能不断提高,且随着排水能力的增强土体长期性能也不断增强。

Taking the dredger fill in Tianjin Binhai Tourist Area as the test material,the combination of impact load,drainage condition,impact number and impact number were used as the variables to simulate the on-site impact load for ground treatment,and the treated soil was subjected to static triaxial test..The test results show that the long-term performance of the soil is obviously affected by the impact load and is related to the soil structure.When the impact load is lower than the yield stress of the dredger fill structure,the creep deformation of the soil gradually decreases with the increase of the impact load,and the long-term strength increases continuously.When the impact load is greater than the yield stress of the dredger fill structure,the soil structure A lot of damage,long-term performance is weakened.Under the condition that the impact load is lower than and close to the yield stress of the soil structure,both the impact mode and the drainage condition have an effect on the long-term performance of the soil.When the impact energy is the same,the impact between the soil particles increases as the number of impacts increases.The structure is more encrypted,the long-term performance is continuously improved,and the long-term performance of the soil is also enhanced with the improvement of drainage capacity.