摘要
引江济淮工程江淮沟通段非膨胀土资源紧缺,依托试验工程开展河道开挖弃渣弱膨胀土、崩解性砂岩资源化研究,开发非膨胀土生产技术。依据弱膨胀土降低含水率实验确定最优降低含水率工艺,利用崩解性粉砂岩天然含水率低、膨胀性弱且容易粉末化的属性,开发'原料弱膨胀土+崩解岩粉+改性剂(水泥)'复合改良非膨胀土。研究表明,使用农用旋耕机翻晒弱膨胀土具有更高的风干效率,水泥和工业盐作为外掺剂加速弱膨胀土风干的效果不明显;弱膨胀土掺入总量不超过30%的崩解岩粉作为改性土原料,可满足非膨胀土成品渗透性和压实性要求且能提高相关技术指标;原料弱膨胀土含水率与改性土压实度负相关,可通过增大压实功抵消不良级配对压实度的负面影响;改性土内水泥分布均匀性检测结果受取样间距影响,取样间隔不宜超过40 m,对应均匀度指标为0.7~0.8。
Due to the shortage of non-expansive soil resources in the Jiang-Huai section of the project of Yangtze River to Huaihe River water diversion, the study on the reclamation of weak expansive soil and slaking sandstone from the excavated and abandoned slag in the river course is carried out based on the experimental project, and the production technology of non-expansive soil is developed. According to the experiment of reducing water content of weak expansive soil, the optimal method of reducing water content of weak expansive soils is determined. Based on the properties of natural low moisture content, weak expansion and easy powder formation of slaking sandstone, a composite modified soil comprising 'primarily of weak expansive soil, slaking rock powder and modifier(cement)' is developed. The study shows that compared with road mixer and plough, rotary tiller have a higher efficiency in reducing soil moisture content. The desired effect is not achieved by using cement and industrial salt as admixture to accelerate the reduction of water content. Slaking rock powder with less than 30% of the incorporation amount of weak expansive soil as the raw material of modified soil can meet the permeability and compaction requirements of non-expansive soil finished products and can improve relevant technical indexes. The moisture content of the expansive soil is negatively correlated with the degree of compaction of modified soil. The degree of compaction can however be increased by additional compaction of soil. The test results of cement distribution uniformity of the modified soil are related to the sampling interval. The sampling interval should not exceed 40 m, and the corresponding uniformity index should be 0.7-0.8.
作者
李国维
施赛杰
侯宇宙
吴建涛
李峰
吴少甫
LI Guo-wei;SHI Sai-jie;HOU Yu-zhou;WU Jian-tao;LI Feng;WU Shao-pu(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing, Jiangsu 210098, China;Highway and Railway Research Institute, Hohai University, Nanjing, Jiangsu 210098, China;Geotechnical Research Institute, Hohai University, Nanjing,Jiangsu 210098, China;Anhui Investment Group Holding Co., Ltd., Hefei, Anhui 230000, China;China Railway 20th Bureau Group Co., Ltd., Xi’an, Shaanxi 710016, China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2018年第S2期302-314,共13页
Rock and Soil Mechanics
基金
国家自然科学基金项目(No.41472240)
中央高校基本科研业务费专项基金(No.2015B25514,No.2015B17214)~~
关键词
引江济淮工程
非膨胀土
膨胀土改良
崩解岩粉
检测指标
water diversion project from Yangtze River to Huaihe River
non-expansive soil
modification of weak expansive soil
slaking rock powder
detection index
