作者：何国平¹, 蔡天德¹, 陈双², 莫忧², 胡建²

作者单位：1. 浙江钜元建设有限公司，浙江 杭州 311600;
2. 四川农业大学水利水电学院，四川 成都 611130

关键词：水泥土;土质固化剂;强度;微观机理

摘要：

为研究土质固化剂对水泥土力学性能的影响及机理，首先开展击实试验以确定最优水泥掺量，然后将不同含量的TG-1型土质固化剂掺入水泥土中制备试样，并开展无侧限压缩实验分析强度的变化规律，同时结合扫描电镜试验结果分析固化水泥土的改性机理。试验结果表明：击实试验结果显示，水泥含量为8%的水泥土试样最大干密度达到峰值，密实度最优；随土质固化剂含量的从0增加至0.05%过程中，改性水泥土的抗压强度、弹性模量逐渐提高，且养护28 d的试样强度指标明显高于养护7 d的试样；随着土质固化剂含量增加，土体内部孔隙的数量与尺度逐渐减小；一定含量的土质固化剂掺入水泥土试样后，形成致密、稳定的凝胶结构，从而提升水泥土的强度。

Research on the effect and mechanism of soil curing agent on mechanical properties of cement soil
HE Guoping¹, CAI Tiande¹, CHEN Shuang², MO You², HU Jian²
1. Zhejiang Juyuan Construction Co., Ltd., Hangzhou 311600, China;
2. College of Water Conservancy and Hydropower Engineering, Sichuan Agricultural University, Chengdu 611130, China
Abstract: In order to study the influence of soil curing agent on the mechanical property of cement-soil and its mechanism, the compaction tests were conducted to determine the optimal dosage of cement. Then, the different contents of TG-1 soil curing agent were mixed in the sample and the unconfined compression tests were carried out. Finally, the modification mechanisms of solidified soil were revealed by combining with Nuclear magnetic resonance (NMR) tests and scanning electron microscopy (SEM) results. The test results show that the maximum dry density of cement stabilized soil with 8% content reaches the peak and the density is the best. With the increase of soil curing agent content from 0 to 0.05%, the unconfined compressive strength q_u and elastic modulus E of modified soil gradually increase. The longer the curing time, the greater the increase in q_u and E. With the increase of soil curing agent content, the number and scale of pores in soil decreases gradually. The characteristics of microstructure changes indicate that TG-1 curing agent is added to cement soil samples to form a dense and stable gel structure, which solidifies the cracks between cement-soil aggregates.
Keywords: cement soil;soil curing agent;strength;micro mechanism
2021, 47(6):63-67  收稿日期: 2020-12-17;收到修改稿日期: 2021-01-23
基金项目: 四川省教育发展研究中心课题（CJF19096）
作者简介: 何国平(1977-),男,浙江杭州市人,高级工程师,主要从事建筑材料方面的研究
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