絮凝固化联合真空预压处理高含水率淤泥(浆)试验研究  

Experimental study on flocculation-solidification combined with vacuum preloading treatment of dredged mud with high moisture content

作　　者：徐志豪 章荣军[1] 郑俊杰[1] 屠林伟 XU Zhihao;ZHANG Rongjun;ZHENG Junjie;TU Linwei(Institute of Geotechnical and Underground Engineering, Huazhong University of Science and Technology, Wuhan 430074, P.R. China)

机构地区：[1]华中科技大学岩土与地下工程研究所,武汉430074

出　　处：《土木与环境工程学报（中英文）》2021年第5期10-18,共9页Journal of Civil and Environmental Engineering

基　　金：国家重点研发计划(2016YFC0800200);国家自然科学基金(51678266、51978303)。

摘　　要：絮凝固化联合法(FSCM)是超高含水率疏浚泥浆(EHW-MS)处理和循环利用的合理选择。然而,面向对填料力学性能要求较高的资源化利用情形时,FSCM在固化效率上仍存在一定的局限性。在FSCM的基础上,引入低位真空预压技术(VP),对EHW-MS用作路堤填料提出一套新的技术方法——真空预压絮凝固化联合法(VP-FSCM),以达到淤泥浆深度脱水、提高固化效率的目的。通过室内模型试验确定VP-FSCM的优越性,并探究其处理优势随等效初始含水率的变化规律;结合微观测试手段,分析和论证VP-FSCM的内在机理和可行性。结果表明:采用VP-FSCM能使试样的不排水抗剪强度最高提高至FSCM的1.65倍,并且强度优势稳定在1.2倍以上。其处理优势在微观层面上表现为C(A)SH凝胶、钙矾石等水化产物数量及发育程度得到明显提升,能进一步填充与密实土体结构。Flocculation-solidification combined method(FSCM)is a reasonable choice for the treatment and recycling of extra-high water content dredged mud slurry(EHW-MS).However,FSCM still has certain limitations in curing efficiency when the treated EHW-MS is recycled as filling material with high requirement on mechanical properties.In order to achieve the purpose of deep dehydration of dredged mud slurry and improve the efficiency of solidification,low-position vacuum preloading technology(VP)is introduced on the basis of FSCM,and a new technical method for EHW-MS used as embankment filler has been proposed-vacuum preloading-flocculation-solidification combined method(VP-FSCM).A series of indoor model tests had been carried out to verify the advantages of the VP-FSCM,and to explore the law of its processing advantages with the equivalent initial moisture content;In addition,combined with microscopic testing methods(e.g.XRD and SEM),the internal mechanism and feasibility of VP-FSCM have been analyzed and demonstrated.The results show that the undrained shear strength of the VP-FSCM treated EHW-MS can be increased to 1.65 times than that of FSCM,and the strength advantage is maintained at least 1.2 times.On the micro level,the processing advantage of VP-FSCM is that the quantity and development of hydration products such as C(A)SH gel and ettringite are significantly improved,and the soil structure are further filled and compacted.

关 键 词：疏浚淤泥浆 固化 絮凝 真空预压 抗剪强度 含水率 

分 类 号：TU432[建筑科学—岩土工程]