强风化岩流态固化土抗压强度试验研究  

Experimental Study on Compressive Strength of Fluid-solidified Soil of Strongly Weathered Rock

作　　者：张鑫 吉海峰 金生莲 朱彦鹏[2,3] 王浩[2] 黄安平 ZHANG Xin;JI Haifeng;JIN Shenglian;ZHU Yanpeng;WANG Hao;HUANG Anping(Gansu West Geotechnical Engineering Co.,Ltd.,Lanzhou,Gansu 730050,China;School of Civil Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;Western Engineering Research Center of Disaster Mitigation in Civil Engineering of Ministry of Education,Lanzhou,Gansu 730050,China)

机构地区：[1]甘肃西部岩土工程有限责任公司,甘肃兰州730050 [2]兰州理工大学土木工程学院,甘肃兰州730050 [3]西部土木工程防灾减灾教育部工程研究中心,甘肃兰州730050

出　　处：《水利与建筑工程学报》2024年第4期85-91,共7页Journal of Water Resources and Architectural Engineering

基　　金：国家自然科学基金面上项目(51978321);教育部长江学者和创新团队支持计划项目(IRT17R51);湿陷性黄土、砂质泥岩、红砂岩及再生骨料场地基槽流态填充材料配合比试验研究(032664)。

摘　　要：为解决生态环境与工程投资效益之间的关系,以兰州某回填工程为依托,将开挖出的强风化岩与湿陷性黄土混合后添加适量的水泥、膨润土和泵送剂进行改良后作为流态填充材料,应用正交试验设计,对不同配比的强风化岩流态固化土进行无侧限抗压强度试验,得到各因素最佳配比,分析抗压强度的影响因素及其显著性大小,并研究强风化岩流态固化土的水稳定性和冻融循环作用下的微观结构。结果表明:对抗压强度影响最显著的因素是水泥,黄土次之;各因素对抗压强度影响的大小排序依次为:水泥掺量→黄土掺量→膨润土掺量→强风化岩粗骨料掺量→强风化岩细骨料掺量→泵送剂掺量。改良试样浸水后抗压强度随养护龄期增长下降幅度逐渐趋于平缓,说明其水稳定性得到了提高;在冻融循环作用下易发生硅含量损失,且改良试样的强度性能与硅元素有关。In order to analyze the relationship between ecological environment and engineering investment benefits,the excavated strongly weathered rock mixed with collapsible loess is improved by adding appropriate amount of cement,bentonite and pumping agent as fluid filling material.Based on a backfill project in Lanzhou,an orthogonal design was applied to test and investigate the unconfined compressive strength of fluid-solidified soil with different ratios of strongly weathered rock to obtain the best ratio of each factor.The influencing factors of compressive strength,its significance magnitude,and the water stability and freeze-thaw cycles under the microstructure of fluid-solidified soil of strongly weathered rock were analyzed.The results are as follows.The most significant factor affecting the compressive strength is cement,followed by loess.The influence of each factor on the compressive strength is in the following order:cement content,loess content,bentonite content,strong weathering rock coarse aggregate content,strong weathering rock fine aggregate content and pumping agent content.The compressive strength of the improved sample after water immersion gradually tends to level off with the growth of the maintenance age,indicating that its water stability performance has been improved.They are prone to Si content loss under freeze-thaw cycles,and the strength properties of the improved sample is related to Si element.

关 键 词：强风化岩 正交试验 流态固化土 抗压强度 水稳定性 微观分析 冻融循环 

分 类 号：TU502[建筑科学—建筑技术科学]