咸水区水泥土桩劣化及改性对道路复合地基的影响  

The influence of soil-cement pile deterioration and modification in salt-water area on road composite foundation

作　　者：王忠啸 崔新壮[1,2] 崔社强 张磊 车华桥[1] 苏俊伟[1] WANG Zhongxiao;CUI Xinzhuang;CUI Sheqiang;ZHANG Lei;CHE Huaqiao;SU Junwei(School of Civil Engineering,Shandong University,Jinan 250061,Shandong,China;Shenzhen Research Institute,Shandong University,Shenzhen 518057,Guangdong,China)

机构地区：[1]山东大学土建与水利学院,山东济南250061 [2]山东大学深圳研究院,广东深圳518057

出　　处：《山东大学学报（工学版）》2018年第4期69-77,共9页Journal of Shandong University（Engineering Science）

基　　金：国家自然科学基金资助项目(51778346;51479105);深圳市科技研发基金资助项目(JCYJ20160429183630760)

摘　　要：为了揭示咸水区水泥土桩劣化及改性对道路复合地基的影响,通过室内试验分析黄河三角洲土水的理化性质,研究含盐水泥土的力学特性。基于莫尔-库伦本构模型和强度折减法,利用FLAC3D模拟水泥土桩劣化及改性对复合地基沉降和承载特性的影响。研究发现:地下水基本上为矿化度大于5 g/L的盐水,盐分以氯化物为主;盐的腐蚀作用会使水泥土发生劣化而强度降低;水泥土桩劣化会增大复合地基沉降,降低桩体承载能力;用矿渣微粉对水泥土桩改性可有效提高桩体承载能力、减小复合地基沉降。为此,在咸水区复合地基设计中,充分考虑水泥土桩的劣化效应是确保路基在全寿命周期内具有足够强度和稳定性的关键。In order to reveal the influence of soil-cement pile deterioration and modification in salt-water area on road composite foundation,the physical and chemical properties of soil and water in the YellowRiver Delta were analyzed through laboratory experiments,and the mechanical properties of salty soil-cement were studied. Based on Mohr-Coulomb constitutive model and strength reduction method,the influence of soil-cement pile deterioration and modification on the settlement and load-bearing properties of composite foundation were stimulated by FLAC3 D. Research showed that,groundwater was basically saltwater with a salinity greater than 5 g/L and the salt was mainly chloride. The corrosion of salt caused deterioration of soil-cement with reduced strength. The deterioration of soil-cement pile increased the settlement of composite foundation and reduced the bearing capacity of pile. It could be effectively improved the bearing capacity of pile and reduced the settlement of composite foundation by using slag powder to modify soil-cement pile. Therefore,in the design of composite foundation,fully considering the deterioration effect of soil-cement pile is the key to ensure that the subgrade has sufficient strength and stability throughout its life cycle.

关 键 词：道路工程 咸水区 水泥土桩劣化 材料改性 复合地基 数值模拟 

分 类 号：TU472.3[建筑科学—结构工程]