羧甲基纤维素钠改良土强度影响因素研究

Strength Influencing Factors of Sodium Carboxymethyl Cellulose Modified Soil

边坡防护工程中常使用无机胶凝材料(水泥、石灰等)作为黏合剂、固化剂以改善土体的力学性能,但无机材料的过度使用对自然生态环境带来巨大负担。羧甲基纤维素钠(CMC)是一种环境友好型生物高分子聚合物,同样具有改善土体结构、提高力学强度的性能。通过向粉质黏土中掺入CMC,研究了CMC对黏性土的改良效果及规律。结果表明:在粉质黏土中加入CMC能有效提高其抗剪强度。对比了湿法和干粉两种处理方式,干法拌和直接掺入CMC后的改良土强度能获得更高的提升。研究了CMC掺入量、含水量、养护时间等对CMC改良土的影响;当CMC掺入量为2%、控制含水率为15%时,对土体强度的提高幅度最大。

Inorganic cementing materials(cement, lime, etc.) are often used as binder and curing agent in slope protection projects to improve the mechanical properties of soil, but the excessive use of inorganic materials brings great burden to the natural ecological environment. Sodium Carboxymethyl Cellulose(CMC) is an environment-friendly biopolymer with the same properties of improving soil structure and mechanical strength. In this study, the improvement effect and law of CMC on Silty clay were tested by adding CMC into the soil. The results show that adding CMC to the soil can effectively improve its shear strength. Compared with the two treatment methods of aqueous solution and dry powder mixing method, the strength of the modified soil after directly adding CMC dry powder can be improved. The effects of mixing amount of CMC, water content and curing time on the CMC modified soil were analyzed. When the content of CMC was 2% and the moisture content was controlled at 15%, the improvement of soil strength was the largest.