水泥固化滨海风积砂三轴试验研究

为了研究水泥对滨海风积砂的固化作用,设计了一系列三轴试验,分析了在高含水量状态下有效围压、水泥剂量和龄期对风积砂应力—应变曲线和孔压曲线发展规律的影响。结果表明:纯砂样的偏应力峰值和初始有效围压的拟合关系近似呈线性关系;在CD试验中,随着水泥剂量的增大,试样偏应力峰值明显增强,但低水泥剂量(2%)下偏应力峰值反而比纯砂样低;在CU试验中,由于水泥阻碍了孔压的消散,使得试样强度反而比砂样的略为降低;胶结样峰值强度与水泥剂量的拟合关系近似呈二次项关系;和7天相比,龄期28天对强度的贡献不大。试验结论对研究滨海地区风积砂路用性能具有实用价值。

Experimental Study on Coastal Aeolian Sand Stabilized by Cement by Triaxial Test

A series of tri-axial tests were carried out to study the solidification effect of cement for coastal aeolian sand. The results were analyzed to research the influences of different initial effective confining pressures, cement dosage and curing age on the stress-strain relationship and the development of pore pressure under high water content. The study shows that the peak deviatoric stress increases nearly linearly with the initial effective confining pressure for pure sand. In the drained tests, the peak deviatoric stress increased obviously if more cement was used. However, when small amount of cement was applied (2%), the strength was lower than that of pure sand. In undrained tests, the total strength of cemented sand dropped slightly because the pore pressure dissipation was blocked by the cement. The relationship of the peak strength and the dosage of cement present approximately quadratic for cemented sand. By comparing results from different curing ages, the strength of samples cured for 28 days was similar with that of samples cured for 7 days. The study is of important practical value for the performance of coastal aeolian sand.