摘要
目前,絮凝-固化联合法(flocculation-solidification combined method,简称FSCM)是高含水率疏浚流泥(high-water-content dredged mud slurry,简称HW-MS)处理及资源化利用的重要选项。大量既有试验结果已经证实了絮凝剂对改性流泥脱水性能的显著提升作用及其促进脱水而产生的强度成倍增长效应。但由于多重物理、化学作用的涉入,絮凝剂是否会对固化反应进程及固化流泥的剪切行为和变形特性产生其他附加影响(除了促进脱水程度提升而引起强度增长之外的影响)尚不明确。鉴于此,通过开展一维固结试验、无侧限抗压强度试验以及三轴固结不排水剪切试验,对比分析不脱水条件下FSCM与传统固化法(pure cement solidification method,简称PCSM)改性流泥的压缩变形特性与三轴剪切特性的异同,同时探究不同固化剂掺量条件下絮凝剂对改性流泥的强度行为及变形特性的影响规律及机制;并结合场发射扫描电镜(field acoustic emission scanning electron microscope,简称FESEM)试验,从微观层面揭示了内在机制。结果表明:即使在不脱水条件下,絮凝剂的涉入不会对改性流泥的强度发展产生负面影响,但可以显著提升改性流泥的韧性,在峰值强度相近的条件下,FSCM固化流泥的破坏应变明显大于PCSM改性流泥,其应力-应变行为由脆性行为向延性行为转变。絮凝剂对改性流泥韧性的改善将有助于提升改性流泥填筑体安全性及其抗干湿冻融循环能力。
Currently,the flocculation-solidification combined method(FSCM)is a significant approach for the treatment and resource utilization of high-water-content dredged mud slurry(HW-MS).Extensive experimental evidence has demonstrated that flocculants significantly enhance the dewatering performance of slurry-like mud and amplify the strength multiplier effect through dehydration promotion.However,due to the complexity of the involved physicochemical processes,it remains unclear whether flocculants have additional effects on the curing reaction,shear behavior,and deformation characteristics of solidified mud beyond their role in enhancing dehydration and strength.Based on this,one-dimensional consolidation tests,unconfined compressive strength tests,and triaxial undrained shear tests were conducted to compare and analyze the compression,deformation,and triaxial shear characteristics of FSCM-and pure cement solidification method(PCSM)-treated slurry-like mud under no-dewatering conditions.Additionally,the study investigates the influence of flocculants on the strength and deformation characteristics of modified slurry-like mud under varying cementitious binder contents,focusing on the underlying mechanisms and patterns.Furthermore,field acoustic emission scanning electron microscope(FESEM)analyses revealed the intrinsic mechanism at the microscopic level.The results show that,even without dehydration,flocculant addition does not adversely affect the strength development of modified slurry-like mud but significantly enhances its toughness.Under similar peak strength conditions,FSCM solidified slurry-like mud exhibits significantly higher failure strain compared to PCSM solidified mud,with its stress-strain behavior transitioning from brittle to ductile.Flocculant-induced toughness enhancement improves the safety and freeze-thaw resistance of modified slurry-like mud fills.
作者
吴倩婵
章荣军
徐志豪
杨钊
郑俊杰
WU Qian-chan;ZHANG Rong-jun;XU Zhi-hao;YANG Zhao;ZHENG Jun-jie(School of Civil Engineering,Wuhan University,Wuhan,Hubei 430072,China;Rock Mechanics in Hydraulic Structural Engineering,Ministry of Education,Wuhan University,Wuhan,Hubei 430072,China;CCCC Second Harbor Engineering Company Ltd.,Wuhan,Hubei 430040,China)
出处
《岩土力学》
北大核心
2025年第S1期205-216,共12页
Rock and Soil Mechanics
基金
湖北省重点研发计划(No.2022BAA068)
国家自然科学基金(No.52122806,No.52338007)
中央高校基本科研业务费专项资金资助(No.2042023kfyq03)
关键词
流泥
絮凝
固化
强度
应力-应变行为
变形特性
slurry-like mud
flocculation
solidification
strength
stress-strain behavior
deformation characteristics
