刺槐豆胶改良黏土强度抗压抗拉力学特性试验研究

Experimental Study on Compressive and Tensile Properties of Locust Bean Gum Modified Clay Soil Strength

为了研究刺槐豆胶改良黏土强度的效果,对不同养护龄期、刺槐豆胶掺量的改良黏土分别进行无侧限抗压强度试验以及抗拉试验研究。结果表明:刺槐豆胶的掺入可以显著改善黏土的抗压和抗拉性能。当养护龄期一定时,随着刺槐豆胶掺量的增加,改良黏土的抗压和抗拉强度均呈增长趋势,通过对比可知,刺槐豆胶的最优掺量为2%,试样的抗压和抗拉强度的最大值分别提升至425.74及234.61 kPa,与素土相比均提高约1.8倍;当刺槐豆胶掺量一定时,养护龄期对改良黏土的抗压、抗拉强度也有一定的影响。在刺槐豆胶掺量相同的条件下,养护龄期为7 d时,试样抗压、抗拉强度提升量最大,最大提升量分别为68.12和34.39 kPa。刺槐豆胶在土体表层形成一层胶质薄膜,并利用自身延展性填充土颗粒间孔隙,改善了土体的粒间结构,增强土体的稳定性,从而提升黏土的强度特性。随着养护龄期的增加,胶质薄膜逐渐收缩,使土体颗粒排列更加紧密,进而提高改良黏土体的无侧限抗压强度及抗拉强度。

In order to study the effect of locust bean gum to improve the strength of clay,unconfined compressive strength tests and tensile tests were conducted on improved clay with different curing ages and locust bean gum contents.The results indicate that the addition of locust bean gum can signifi-cantly improve the compressive and tensile properties of clay.When the curing age is fixed,with the increase of the locust bean gum content,the compressive and tensile strengths of the improved clay show an increasing trend.Through comparison,it can be seen that the optimal content of locust bean gum is 2%,and the maximum compressive and tensile strengths of the sample are increased to 425.74 and 234.61 kPa,respectively,which are about 1.8 times higher than those of the plain soil;When the dosage of locust bean gum is constant,the curing age also has a certain impact on the compressive and tensile strengths of the improved clay.Under the same dosage of locust bean gum,when the cu-ring age is 7 days,the specimen compressive and tensile strength enhancement is the largest,the maximum enhancement is 68.12 and 34.39 kPa,respectively.Robinia pseudoacacia bean gum forms a layer of gum film on the surface of soil,and uses its own ductility to fill the pores between soil particles,improving the particle structure of the soil and its stability,and thus the strength character-istics of clay.As the curing age increases,the gum film gradually shrinks,making the arrangement of soil particles more compact,thereby improving the unconfined compressive strength and tensile strength of the improved cohesive soil.