有机高分子添加剂对水泥固化土的改良  

Improvement of cement-cured soil through organic polymer additive

作　　者：陈景贤 孟艳秋[1] 张超杰[2] CHEN Jingxian;MENG Yanqiu;ZHANG Chaojie(College of Harbour,Coastal and Offshore Engineering,Hohai University,Nanjing 210024,Jiangsu,China;Zhejiang Institute of Hydraulics&Estuary,Hangzhou 310017,Zhejiang,China)

机构地区：[1]河海大学港口海岸与近海工程学院,江苏南京210024 [2]浙江省水利河口研究院,浙江杭州310017

出　　处：《地基处理》2025年第2期156-162,共7页Journal of Ground Improvement

基　　金：浙江省水利科技计划项目(RB2027)。

摘　　要：本研究采用水泥和有机高分子添加剂对钱塘江冲海积粉土进行固化改良,对固化改良后的粉土进行无侧限抗压强度试验,研究有机高分子添加剂的种类、掺量以及复合高分子添加剂的配比对固化改良粉土强度的影响,并通过微观电镜扫描分析有机高分子添加剂对粉土改良的作用机理。试验结果表明:羧甲基纤维素钠(CMC)和聚阴离子纤维素−高粘(PAC-HV)都能促进水泥固化土强度的提升,并有明显的峰值强度,而聚丙烯酰胺(PAM)的掺入会对水泥固化土的强度造成负面影响,随着掺量的提升,水泥固化土的强度随之降低;有机高分子添加剂CMC和PAC-HV在保持固化土强度的基础上,通过降低变形模量显著改善其变形性能,使土体更容易产生形变,降低外部的冲击应力,更好地吸能。另外,微观分析表明,CMC与PAC-HV通过与水泥反应形成柔性网络结构,优化了孔隙分布并桥接微裂纹,从而在提升变形能力的同时避免结构失稳。本研究结果为采用有机高分子添加剂改良钱塘江冲海积粉土提供了一定的参考依据。This study focuses on the solidification and improvement of Qiantang River alluvial-marine silt using cement and organic polymer additives.Unconfined compressive strength tests were conducted to investigate the effects of the type and dosage of organic polymer additives,as well as the mixing ratio of composite polymer additives,on the strength of the improved silt.Additionally,the mechanism of organic polymer additives in silt improvement was analyzed using scanning electron microscopy(SEM).The test results show that both CMC and PAC-HV can enhance the strength of cement-cured silt,exhibiting distinct peak strengths.In contrast,the incorporation of PAM has a negative impact on the strength of cement-cured silt,leading to a decrease in strength with increasing dosage.Organic polymer additives CMC and PAC-HV significantly improve the deformation performance of solidified soil by reducing its modulus of deformation while maintaining soil strength.This modification enables the soil mass to deform more readily,thereby reducing external impact stresses and enhancing energy absorption capacity.Microstructural analysis reveals that CMC and PAC-HV interact with cement to form flexible network structures,which optimize pore distribution and bridge microcracks.This mechanism enhances deformability while preventing structural instability.The results provide a reference for the application of organic polymer additives in improving Qiantang River alluvial-marine silt.

关 键 词：水泥固化粉土 有机高分子添加剂 无侧限抗压强度 变形模量 微观 改良机理 

分 类 号：TU41[建筑科学—岩土工程]