橡胶颗粒改良膨胀土路基的三轴应力试验研究

Experimental Study on Triaxial Stress of Rubber Granule Modified Expansive Soil Roadbed

摘要:

为探究橡胶颗粒改良膨胀土路基的抗剪切性能，以南京市江宁区某地的弱-中等膨胀土为试验对象，在不同橡胶掺量和各级围压下进行三轴固结不排水（CU）试验。试验结果表明：随着橡胶掺入量的上升，土体黏聚力呈持续下降趋势，内摩擦角先增大，在10%橡胶掺量时几乎维持不变，而后减小；土体抗剪强度在橡胶掺入量为5%时取得最大值。在掺胶率大于10%时，改良土黏聚力和抗剪强度大幅下降，在应用到膨胀土改良工程时，需要有所考虑。

Abstract:

To explore the shear resistance of rubber granule modifed expansive soil roadbed, the triaxial consolidation no-drainage (CU) test is conducted with different rubber admixtures and confining pressure at all levels by taking the weak-medium expansive soil in Jiangning District of Nanjing as a test object. The test results show that the cohesive force of the soil tends to decrease continuously with the increase of rubber admixture. The angle of internal friction increases first, and then remains unchanged at 10% rubber admixture, and then decreases. The shear strength of the soil achieves the maximum value at 5% rubber admixture. The cohesive force and shear strength of the modified soil will greatly decrease when the rubber admixture rate is more than 10%, which needs to be considered when applied to the modification project of expansive soil.