制样方法对软土力学特性影响的试验研究

Experimental Study of the Effect of Sample Preparation Methods on the Mechanical Properties of Soft Soils

本文提出了一种新的人工制备结构性软土制样方法,并将其命名为风吹沉积固结法,详细介绍了其制样装置与制样步骤。采用高岭土作为试验材料来进行制样,通过试验对比分析了风吹沉积固结法和搅拌沉积固结法的制样过程以及两种制样方法所制备的土样在三轴固结不排水剪切试验中所表现出的力学特性。试验结果表明,采用风吹沉积固结法制样时,土样的自重固结时间更短,沉积稳定后土样的孔隙比更小,该制样方法消除了搅拌沉积固结法制样时会卷入空气的弊端。两种制样方法均可以制备出具有结构性的软土样,但两土样所呈现出的力学特性存在一定差异,风吹沉积固结法所制土样的结构性要比搅拌沉积固结法所制土样的结构性强。

A new method for the preparation of artificially prepared structural soft soil samples was proposed and it was named as wind-blown deposition consolidation method.Kaolin clay was used as the experimental material for sample preparation.The sample preparation processes of wind-blown deposition consolidation method and stirred deposition consolidation method and the mechanical properties of the specimens prepared by the two sample preparation methods in triaxial consolidation undrained shear tests were compared and analyzed.The test results show that the self-weight consolidation time of the soil samples is shorter and the void ratio of the samples is smaller after deposition and stabilization when the samples are prepared by the wind-blown deposition consolidation method,which eliminates the disadvantage of air entrapment when the samples are prepared by the stirred deposition consolidation method.Both sample preparation methods can produce soft soil samples with structural properties,but the mechanical properties presented by the two soil samples are somewhat different.The structural properties of soil samples made by wind-blown deposition consolidation method are stronger than those made by stirred deposition consolidation method.