衰减源作用下固结压力及吸附参数对污染物运移规律的影响

固结变形会导致粘土防渗层的结构特性和渗透特性发生改变,影响渗流场和浓度场的分布,进而影响污染物在防渗层中的运移规律。在比奥固结理论的基础上,考虑线性吸附模式,研究了污染物在小变形土体中的运移规律,分析了衰减源作用下,固结压力与线性吸附系数对污染物运移过程的影响。结果表明,与不考虑固结作用相比,固结作用延迟了污染物的运移,使得污染物运移深度减小,并且随着固结压力的增大,固结作用对污染物运移的延迟作用逐渐增强;在线性吸附模式情况下,污染物运移深度减小率随着吸附系数的减小逐渐增大,说明固结作用对污染物运移的延迟作用随着吸附系数的减小而越来越凸显。

Effect of Consolidation Pressure and Adsorption Parameter on Contaminant Transport Considering the Biodegradation of Contaminant at Source

Consolidation deformation can lead to changes of structural and permeable characteristics of clay impermeable layer, which will affect the distribution of seepage field and concentration field, and then affect the transport law of contaminant in impermeable layer. Based on the Biot consolidation theory, the transport law of contaminant in deforming soil is studied taking account. Meanwhile, the effects of consolidation pressures and adsorption parameters have been analyzed separately. The results show that consolidation deformation retards the transport process of contaminant and shortens the transport depth of contaminant. In addition, the retardation of consolidation deformation on the transport process of contaminant becomes stronger as the consolidation pressure increases. Meanwhile, under the condition of a linear adsorption mode, the decreasing rate of migration depth increases gradually as the adsorption parameter decreases. It is shown that the retardation of consolidation deformation on the transport process of contaminant becomes more visible when the adsorption parameter decreases. The results have important theoretical significance for the design of effective thickness of the simple constructed garbage dump and bottom sediment dump, as well as the safety evaluation of impermeable layer.