有机硅材料改良膨胀土的工程特性试验研究

Experimental Study on Engineering Characteristics of Expansive Soil Improved by Silicone Material

通过对不同掺量的有机硅材料改良膨胀土进行膨胀特性和强度特性试验,探讨有机硅材料对膨胀土工程特性的改良效果以及作用机理,并与传统石灰改良膨胀土的改良效果进行对比分析。研究结果表明:随着有机硅材料掺量的增加,改良膨胀土的膨胀量指标均呈现逐步降低的趋势;有机硅材料能够提高膨胀土浸水前后无侧限抗压强度、软化系数和粘聚力,提高膨胀土的水稳定性;有机硅材料改良膨胀土与素膨胀土浸水饱和条件下应力应变关系主要表现为应变硬化型;有机硅材料的合理掺比为1.5%,此时,有机硅材料限制膨胀土膨胀变形的能力与4%掺量的石灰相当,其强度及水稳定性均优于4%掺量的石灰。

The improvement effect and mechanism of silicone material on the engineering characteristics of expansive soil were discussed through experiments on the expansion and strength characteristics of modified expansive soil with different contents of silicone material,and the effect was compared with that of traditional lime.The results show that with the increase of the content of silicone material,the expansion indexes of modified expansive soil show a trend of gradual decrease.Silicone material can improve the unconfined compressive strength,softening coefficient and cohesion of expansive soil before and after water immersion,and improve the water stability of expansive soil.The stress-strain relationship between silicone material modified expansive soil and plain expansive soil is mainly strain hardening type under saturated conditions.The reasonable mixing ratio of silicone material is 1.5%,at this time,the ability of 1.5%silicone material to limit the expansion deformation of expansive soil is similar to that of 4%lime,and its strength and water stability are better than of 4%lime.