南京粉质粘土与粉砂互层土及粉细砂的抗液化性能试验研究

南京粉质粘土与粉砂互层土为粉质粘土与粉细砂交互沉积,呈现“千层饼”状外貌;南京粉细砂是一种以片状颗粒成分为主的粉细砂,与通常的圆形颗粒石英砂有一定区别,片状颗粒成分使得南京粉细砂具有各向异性的性质。通过南京粉质粘土与粉砂互层土及粉细砂对比液化试验,对其试验成果进行分析,从中发现:无论是偏压固结还是均压团结,当固结压力α_2=100 kPa时,南京粉质粘土与粉砂互层土的液化剪应力比比南京粉细砂的大得多;而当固结压力α_2=200kPa时,两种土的液化剪应力比相当接近。因而,对于重大工程应该慎重考虑它们的液化可能性。

Experimental Study of Liquefaction Resistant Characteristics of Silty Clay with Fine Sand Interbed and Fine Sand in Nanjing

Nanjing silty clay with fine sand interbed is a sediment deposited alternately by silty clay and fine sand, appearing to be a "thousand layers cake"; Nanjing fine sand mainly consists of schistous grain and is different from the common sand with round quartz grains. Nanjing fine sand is anisotropic because of the schistous grain. Through analyzing liquefaction test results of Nanjing silty clay with fine sand interbed and fine sand, the following conclusions are drawn: wheither anisotropic consolidation or isotropic consolidation, the ratio of liquefaction shear stress of Nanjing silty clay with fine sand interbed is larger than that of fine sand when consolidation pressure σ'3 is 100 kPa; however, the both are proximity when consolidation pressure σ'3 is 200 kPa. So, liquefaction potential of these soils should be considered carefully in important or critical engineerings.