渠堤填筑中风积砂改性剂配方与特性研究

发布时间：2018-02-11 03:35

本文关键词： 渠堤填筑材料风积砂改性剂保水性能力学性能机理分析　出处：《南京理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：在沙漠地区进行渠堤建设需要大量的渠堤填筑材料风积砂,但风积砂工程性质差,针对这一问题,本文开展了风积砂改性剂的研究与开发,以提高风积砂的保水性能与力学性能。本文在系统地分析风积砂工程性质的基础上,研发了一种风积砂改性剂,通过改性剂入渗试验、水分迁移试验、重型击实试验、直接剪切试验对比分析,最终选择出一组最佳配方,并对改良机理进行了分析。研究结果表明:(1)羧甲基纤维素钠和聚丙烯酰胺对缓渗效果影响较小,单独掺入水玻璃可以有效减缓水分迁移,且缓渗保水效果随水玻璃浓度增大而增强,而单独掺入木质素磺酸钠无法有效发挥缓渗保水作用,但水玻璃和木质素磺酸钠共同施用可以起到较好的缓渗效果,且水玻璃和木质素磺酸钠的最佳配比为10:1。(2)单独加入水玻璃对细砂的最大干密度改良效果较差,而共同施用水玻璃和木质素磺酸钠对砂的最大干密度有一定的改良效果。(3)单掺入水玻璃时,随着水玻璃浓度的增大,细砂的粘聚力、内摩擦角先增大后减小,粘聚力随养护龄期的增长而呈增大趋势。(4)掺入水玻璃与木质素磺酸钠比例为10:1时,随着水玻璃、木质素磺酸钠掺入量的增大,细砂的粘聚力先增大后减小,内摩擦角先减小后增大;粘聚力随养护龄期的增长而呈增大趋势。(5)最佳配方改良风积砂的最大干密度虽没有变化,但最佳含水率区间有所增大。随着龄期的增大,改良风积砂的粘聚力先减小后增大,内摩擦角变化较小,从长期来看,改良风积砂的抗剪强度效果较好。
[Abstract]:The construction of canal dike in desert area requires a large amount of wind sand filling materials, but the engineering properties of aeolian sand are poor. In order to solve this problem, the research and development of wind sand modifier are carried out in this paper. In order to improve the water retention and mechanical properties of eolian sand, a modified agent for aeolian sand was developed on the basis of systematically analyzing the engineering properties of eolian sand. By comparing and analyzing the direct shear test, a group of optimum formula was selected, and the improved mechanism was analyzed. The results showed that sodium carboxymethyl cellulose and polyacrylamide had little effect on the retarded infiltration. Sodium lignosulfonate alone can effectively slow down the water migration, and the effect of water retention increases with the increase of water glass concentration, but sodium lignosulfonate alone can not effectively play the role of water retention. However, water glass and sodium lignosulfonate can improve the maximum dry density of fine sand by adding water glass and sodium lignosulfonate, and the optimum ratio of water glass and sodium lignosulfonate is 10: 1.2). When the water glass and sodium lignosulfonate were applied together, the maximum dry density of sand was improved to a certain extent, and the cohesion of fine sand and the angle of internal friction increased first and then decreased with the increase of water glass concentration. When the ratio of water glass to sodium lignosulfonate is 10: 1, the cohesion of fine sand increases first and then decreases with the increase of sodium lignosulfonate ratio. The internal friction angle decreases first and then increases, and the cohesion increases with the increase of curing age. 5) the maximum dry density of the modified aeolian sand with the best formula does not change, but the range of the optimum moisture content increases with the increase of age. The cohesion of improved aeolian sand decreases first and then increases, and the change of internal friction angle is small. In the long run, the shear strength of improved aeolian sand is better.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV223

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