海相淤泥质固化土强度劣化规律试验研究  

Experimental study on strength deterioration law of marine silty solidified soil

作　　者：乔小雨 商恩梁 王彤 罗昊鹏 Qiao Xiaoyu;Shang Enliang;Wang Tong;Luo Haopeng(CCCC First Harbor Engineering Bureau Fourth Engineering Co.,Ltd.,Nanchang 330004,China;School of Architecture and Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]中交一航局第四工程有限公司,南昌330004 [2]天津大学建筑工程学院,天津300072

出　　处：《工程勘察》2024年第2期8-13,25,共7页Geotechnical Investigation & Surveying

基　　金：中交第一航务工程局有限公司科技研发项目(2021GFW-0281).

摘　　要：针对海相淤泥质软土中水泥搅拌桩成桩效果不佳的问题,选取天津地区某地铁工程施工现场海相淤泥质黏土,通过室内水泥土无侧限抗压强度试验,研究了可溶性盐和有机质含量对海相淤泥固化的无侧限抗压强度(UCS)的影响,并通过扫描电镜(SEM)和X射线衍射(XRD)对其微观结构和物相特征进行分析。结果表明:土壤水泥的强度随可溶性盐和有机质含量的增加而降低,其主要通过破坏和抑制水泥水化产物的形成,进而降低水化产物的胶凝性能,破坏了水泥土结构,导致强度降低。该研究结果对解释海相淤泥质软土固化效果不佳的现象具有重要的意义。Aiming at the poor pile-forming effect of cement mixing piles in marine muddy soft soil,the marine muddy clay at the construction site of a subway project in Tianjin is selected,and the indoor cement-soil unconfined compressive strength tests are conducted to study the influence of soluble salt and organic matter content on the unconfined compressive strength(UCS)of marine silt solidification,and its microstructure and phase characteristics are analyzed by using the scanning electron microscopy(SEM)and X-ray diffraction(XRD).The study results show that the strength of soil cement decreases with the increase of soluble salt and organic matter content,which mainly destroys and inhibits the formation of cement hydration products,thereby reducing the gelling performance of hydration products,destroying the cement-soil structure,resulting in a decrease in strength.The study results are helpful in explaining the poor solidification effect of marine silt soft soil.

关 键 词：海相淤泥质软土 可溶性盐 有机质 无侧限抗压强度试验 微观结构 

分 类 号：TU443[建筑科学—岩土工程]