磷石膏基固化剂改良粉土的无侧限抗压强度及水稳定性研究  

The Study on Unconfined Compressive Strength and Water Stability of Silt Improved by Phosphogypsum-Based Solidifier

作　　者：孙栋 何光锋 常锦 周高翔 SUN Dong;HE Guangfeng;CHANG Jin;ZHOU Gaoxiang(Zhongda Intelligent Technology Co.,Ltd.,Changsha Hunan 410205,China;Guangxi Xinfazhan Communications Group Co.,Ltd.,Nanning Guangxi 530029,China;School of Civil Engineering,Changsha University,Changsha Hunan 410022,China)

机构地区：[1]中大智能科技股份有限公司,湖南长沙410205 [2]广西新发展交通集团有限公司,广西南宁530029 [3]长沙学院土木工程学院,湖南长沙410022

出　　处：《长沙大学学报》2025年第2期26-38,共13页Journal of Changsha University

基　　金：湖南省自然科学基金项目“CFB灰-钢渣微粉多源固废复合注浆材料特性与协同工作机制研究”(2024JJ7618);湖南省重点研发项目“桥梁健康监测专用芯片研制与应用”(2021GK2004)。

摘　　要：为有效利用粉土资源,扩展固体废弃物的资源化利用途径,以磷石膏、矿渣和水泥为主要原材料研制了磷石膏基土壤固化剂。研究采用正交试验方法确定了固化剂配合比,对固化土进行了无侧限抗压强度和水稳定性试验,探究其应用于道路工程建设的可行性。结果表明:水泥矿渣掺量对强度的影响最大,其次是磷石膏掺量,生石灰掺量对强度的影响较小;最优配比为磷石膏掺量为25%,水泥掺量∶矿渣掺量为4∶6 (水泥掺量为28%和矿渣掺量为42%),生石灰掺量为5%;在压实度不低于95%前提下,P25CS46固化土在固化剂掺量为7%~15%时,其7d无侧限抗压强度范围在1.03~2.16 MPa,满足水泥稳定材料应用于中等、轻交通的二级及二级以下公路底基层强度要求;粉土改良后水稳定性良好,固化土28d水稳系数大于80%。To effectively utilize silt resources and expand the resource recovery pathways for solid waste,a phosphogypsum-based soil solidifier was developed using phosphogypsum,slag,and cement as the primary raw materials.Orthogonal experimental methods were employed to determine the mix proportions of the solidifier.Unconfined compressive strength and water stability tests were conducted on the solidified soil to investigate the feasibility for application in road engineering construction.The results indicate that the cement-slag ratio has the greatest influence on strength,followed by the amount of phosphogypsum,while the amount of quicklime has a relatively minor impact on strength.The optimal mix proportions are 25%phosphogypsum,a cement-to-slag ratio of 4∶6(28%cement and 42%slag),and 5%quicklime.With a 95%assurance rate,the 7-day unconfined compressive strength of P25CS46 solidified soil with a solidifier content of 7%to 15%ranges from 1.03 MPa to 2.16 MPa,meeting the strength requirements for the base and subbase layers of secondary and lower-level highways with medium and light traffic for cement-stabilized materials.The water stability of the silt is improved,with the 28-day water stability coefficient of the solidified soil exceeding 80%.

关 键 词：道路工程 粉土 土壤固化剂 磷石膏 

分 类 号：U414[交通运输工程—道路与铁道工程]