固废材料复合固化盐渍土的力学性能  

Mechanical properties and mechanisms of solid waste composite solidified saline soil

作　　者：周志尧 程银银 张喆 王紫 兰永军 李宏波[1,2,3] ZHOU Zhiyao;CHENG Yinyin;ZHANG Zhe;WANG Zi;LAN Yongjun;LI Hongbo(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China;Ningxia Engineering Technology Research Center of Water-saving Irrigation and Water Resources Regulation,Ningxia University,Yinchuan 750021,China;Engineering Research Center of Ministry of Education for Efficient Utilization of Modern Agricultural Water Resources in Arid Regions,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021 [2]宁夏大学宁夏节水灌溉与水资源调控工程技术研究中心,宁夏银川750021 [3]宁夏大学旱区现代农业水资源高效利用教育部工程研究中心,宁夏银川750021

出　　处：《中国粉体技术》2025年第1期130-142,共13页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:52069025;宁夏自然科学基金重点项目,编号:2023AAC02025。

摘　　要：【目的】解决宁夏回族自治区盐渍土地基在盐-冻胀和盐腐蚀作用下存在的强度劣化问题。【方法】采用水泥、粉煤灰、硅灰和砖粉作为固化剂,基于正交试验方案开展无侧限抗压强度试验和三轴剪切试验;通过X射线衍射和扫描电子显微镜等微观表征手段,研究不同固化剂用量对盐渍土无侧限抗压强度和抗剪强度的影响规律,确定较优的盐渍土固化组合。【结果】水泥和硅灰会大幅提高固化盐渍土的无侧限抗压强度,粉煤灰用量的增加会使固化盐渍土的强度呈现先增后减的变化趋势,砖粉的潜在火山灰活性较难激发,需要水泥的水化反应为其提供碱性环境;4种固化剂影响固化盐渍土强度的主次顺序为水泥、粉煤灰、硅灰、砖粉;水泥、粉煤灰、硅灰和砖粉质量分数分别为3%、5%、5%和6%时固化效果最佳;固化盐渍土强度主要受水化硅酸钙、水化铝酸钙、钙矾石等晶体的相互作用,导致土颗粒中晶体和胶凝物的分布从单个和细小的团簇转变为更复杂的三维网络结构,增强土颗粒、盐分和胶凝物之间的结合力。【结论】利用固废材料替代部分水泥固化盐渍土,提高固废资源利用率的同时大幅改善盐渍土地基的抗压和抗剪性能。Objective The saline soil foundation in the Ningxia region experiences significant strength deterioration due to salt-frost heave and salt corrosion.This poses a substantial threat to buildings and infrastructure.To address this,researchers have proposed a novel approach that utilizes solid waste to partially replace cement in stabilizing saline soil.This method not only promotes the use of solid waste resources but also significantly improves the compressive and shear resistance of the saline soil foundation.By addressing both environmental and structural concerns,this approach presents a sustainable solution to the challenges posed by saline soil in Ningxia.Methods This study investigated the use of various curing agents,including cement,fly ash,silica fume,and brick powder,for stabilizing saline soil.To assess the effectiveness of these materials,unconfined compressive strength and triaxial shear tests were conducted based on an orthogonal test scheme.This comprehensive testing approach ensured that the effects of different curing agent contents on the unconfined compressive strength and shear strength of saline soil were thoroughly analyzed.Advanced techniques such as X-ray diffraction(XRD)and scanning electron microscopy(SEM)were employed to examine the microstructural changes in the soil samples.These analyses provided detailed insights into the optimal curing combination for enhancing the properties of saline soil.Results and Discussion The research investigated the impact of various admixtures on the unconfined compressive strength of solidified saline soil.The findings revealed that cement and silica fume significantly enhanced the unconfined compressive strength of the treated saline soil.Cement,known for its strong binding properties,contributed to the formation of a robust matrix that effectively resisted compressive forces.The addition of silica fume,characterized by its fine particle size and high pozzolanic activity,acted as a supplementary cementitious material,further strengthening the matrix and

关 键 词：固化盐渍土 无侧限抗压强度 力学性能 微观分析 

分 类 号：TB4[一般工业技术] TQ324.8[化学工程—合成树脂塑料工业]