黄土力学特性及固化技术研究

发布时间：2018-04-23 21:54

本文选题：黄土 + 力学特性　；参考：《长安大学》2014年硕士论文

【摘要】：我国是黄土分布最广的国家，黄土面积约占我国总陆地面积的6.3%。在基础建设工程中，土是道路的支撑结构。鉴于我国黄土地质特点，需要对黄土力学及黄土固结技术进行研究。本文在介绍了黄土力学特性，并对黄土弹塑性理论回顾的基础上。通过室内试验研究，采用三轴压缩力学试验和重型击实试验、水稳定性试验、低温收缩试验和无侧限抗压强度试验，对黄土、单一石灰固结黄土、石灰+水泥二元固结黄土、石灰+固化剂二元固结黄土以及水泥+石灰+固化剂三元固结黄土的相关物理力学性能进行了研究。通过对黄土力学的研究结果表明，黄土固结过程中，应力-应变曲线呈典型的非线性关系。在加载速率较小条件下，黄土试样产生的偏应力峰值及应变峰值较小；当加载速率较大情况下，，试样偏应力和应变对应的峰值随之增大。在黄土的K0固结过程中，土基的固结过程分为加载阶段与稳压阶段，土体的轴向压缩主要来自于加载阶段。通过对黄土固结技术的研究表明，土壤固化剂改变了土体颗粒的物理化学性质，导致黄土压实过程中的最佳含水量的改变。单一石灰固结土的水稳定性弱于石灰+固化剂二元固结土，弱于石灰+水泥二元固结土，弱于水泥+石灰+固化剂三元固结土。单一石灰固结土的低温收缩性能弱于石灰+固化剂二元固结土；石灰+水泥二元固结土的低温收缩性能弱于水泥+石灰+固化剂三元固结土。本文认为，在土壤固化剂最佳剂量下，水泥+石灰+固化剂的三元固结土适合铺筑于重、中、轻交通的底基层。而石灰+固化剂的二元复合固结土则仅仅可用于各交通量道路的基层。并通过试验段的实际应用，对上述结论进行了验证。
[Abstract]:China is the most widely distributed country with loess area accounting for 6.3% of the total land area. In infrastructure engineering, soil is the supporting structure of the road. In view of the geological characteristics of loess in China, it is necessary to study the loess mechanics and loess consolidation technology. In this paper, the mechanical properties of loess are introduced, and the elastoplastic theory of loess is reviewed. Through laboratory test, triaxial compression test, heavy compaction test, water stability test, low temperature shrinkage test and unconfined compressive strength test were used to treat loess, single lime consolidated loess, lime cement binary consolidated loess. The physical and mechanical properties of lime curing agent binary consolidated loess and cement lime curing ternary consolidated loess were studied. The results of the study on loess mechanics show that the stress-strain curves show a typical nonlinear relationship during the process of loess consolidation. Under the condition of low loading rate, the peak value of deviant stress and strain of loess specimen is smaller, and the peak value of specimen deflection stress and strain increases when loading rate is larger. In the process of K _ 0 consolidation of loess, the consolidation process of soil foundation is divided into loading stage and steady pressure stage, and the axial compression of soil comes mainly from the loading stage. Through the study of loess consolidation technology, it is shown that the physical and chemical properties of soil particles are changed by soil curing agent, which leads to the change of optimum water content in loess compaction process. The water stability of the single lime consolidated soil is weaker than that of the lime curing agent binary consolidation soil, the lime cement dual consolidation soil and the ternary consolidation soil with the cement lime curing agent. The low temperature shrinkage of single lime consolidation soil is weaker than that of lime curing agent binary consolidation soil, and the low temperature shrinkage performance of lime cement dual consolidation soil is weaker than that of ternary consolidation soil with cement lime curing agent. In this paper, under the optimum dosage of soil curing agent, the ternary consolidation soil of cement lime curing agent is suitable for laying on the base of heavy, medium and light traffic. The lime curing agent can only be used in the basic course of each traffic volume road. The above conclusions are verified by the practical application of the test section.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U416.1;U414

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