木钙对兰州黄土水理性质的影响

为揭示木钙对兰州黄土水理性质的影响,基于不同的木钙掺量和养护龄期,通过水滴入渗试验、渗透试验和崩解试验分析木钙土斥水性、渗透性和水稳性,并利用X射线衍射试验、扫描电镜试验探讨木钙土的改良机理。研究结果表明:木钙的掺入可以提升黄土的斥水性、水稳性,低掺量木钙土提升幅度有限,高掺量木钙土整体表现良好,而减弱渗透性的作用有限;木钙土的水理性质发挥具有龄期效应;28 d养护龄期下,木钙土的水理性质参数随木钙掺量的变化存在广义上的峰值,但峰值与木钙掺量的关系存在一定差异;木钙土的水理性质同力学性质保持了一定的正向关联性。木钙土并未产生新的矿物成分,但土颗粒双电层厚度变薄,而且胶结生成物包裹联结颗粒、填充孔隙,从而改善木钙土的水理性质。

Influence of calcium lignosulfonate on the hydrological properties of Lanzhou loess

Based on the different contents of calcium lignosulfonate and curing ages, the water repellency, permeability, and water stability of calcium lignosulfonate were analyzed using the water drop infiltration, penetration, and disintegration tests, respectively, to reveal the influence of calcium lignosulfonate on the hydrological properties of Lanzhou loess. The improvement mechanism of enhanced loess by calcium lignosulfonate is also discussed using X-ray diffraction and scanning electron microscope tests. Results show that the water repellency and stability of loess improved with the addition of calcium lignosulfonate. Moreover, the improvement of calcium lignosulfonate with low content is limited, while the overall performance of loess improved by high-content calcium lignosulfonate is good. However, the effect of reducing permeability is limited. The hydraulic properties of loess improved by calcium lignosulfonate demonstrate age effects: under the curing age of 28 d, a generalized peak value is observed in the hydraulic property parameters of loess improved by calcium lignosulfonate with its content. However, the relationship between peak value and content is different. A certain positive correlation is also observed between the hydraulic and mechanical properties of loess improved by calcium lignosulfonate. No new mineral composition is found in the loess improved by calcium lignosulfonate. However, the thickness of the electric double layer of soil particles becomes thin, and the cementing products wrap the connecting particles and fill the pores, thus improving the hydraulic properties of the loess.