The rainfall effect onto solidification and stabilization of heavy metal-polluted sediments

Rainfall makes impacts on process of solidification/stabilization and the long-term safety of solidified matrix. In this study, the effect of rainfall on solidification/stabilization process was investigated by rainfall test. The unconfined compressive strength (UCS) and toxicity characteristic leaching procedure (TCLP) were adopted to characterize the properties of S/S sediments before and after rainfall test. The samples cured for 28 days were subjected to semi-dynamic leaching tests with a simulated acidic leachant prepared at pH of 2.0, 4.0 and 7.0. Effectiveness of S/S treatment was evaluated by diffusion coefficient (D_e) and leachability index (LX). The results indicated that UCS decreased at maximum deterioration rate of 34.29% of the compressive strength after 7 days of curing, along with minimum rate of 7.89% after 28 days by rainfall, with >14 days referred. The rainfall had little effect on the leaching characteristics of heavy metals during the curing process. The simula...

降雨会对固化/稳定化（Solidification/Stabilization，以下简称S/S）过程以及固化基体的长期安全性产生影响。本研究通过降雨试验，探究了降雨对S/S过程的影响。研究采用无侧限抗压强度（Unconfined Compressive Strength，简称UCS）与毒性特性浸出程序（Toxicity Characteristic Leaching Procedure，简称TCLP），对降雨试验前后S/S沉积物的性能进行表征。将养护28天的试样置于pH分别为2.0、4.0和7.0的模拟酸性浸出液中开展半动态浸出试验。通过扩散系数（Diffusion Coefficient，简称D_e）与浸出指数（Leachability Index，简称LX）评估S/S处理的效果。结果显示，经降雨作用后，养护7天的试样抗压强度最大降幅达34.29%，养护28天的试样抗压强度最小降幅为7.89%，相关分析针对试验周期大于14天的工况。降雨对养护过程中重金属的浸出特性影响极小。本研究的模拟……