水泥改良自重湿陷性黄土耐久性研究

Study on durability of cement improved self weight collapsible loess

为探究水泥改良后的自重湿陷性黄土的耐久性,通过无侧限抗压试验分析压实度、水泥掺量、养护时长、干湿循环次数等因素对改良土水稳定性和耐干湿性的影响,试验结果表明:改良土水无侧限抗压强度随压实度和水泥掺量增大而增大,随养护时长增大而呈先增大后减小的趋势。水稳系数增长幅度随着压实度和养护时间的增加而变小,其压实度宜控制在97%~98%之间,水泥掺量宜控制在8%~10%之间,养护时间宜在28~35d之间。改良土的无侧限抗压强度随干湿循环次数增加而降低;在干湿循环次数相同的条件下,其耐干湿性随掺入水泥量增大而增大,而掺入水泥量小的改良土抗压强度衰减速度较快。

In order to explore the durability of cement improved self weight collapsible loess,the influence of compaction degree,cement content,curing time,dry wet cycle times and other factors on the stability and dry wet resistance of improved soil water is analyzed through unconfined compression test.The test results show that the unconfined compression strength of improved soil water increases with the increase of compaction degree and cement content,and first increases and then decreases with the increase of curing time.The increase range of water stability coefficient decreases with the increase of compactness and curing time.The compactness should be controlled between 97%~98%,the cement content should be controlled between 8%~10%,and the curing time should be between 28~35 days.The unconfined compressive strength of the improved soil decreases with the increase of dry wet cycles;Under the condition of the same number of dry and wet cycles,the dry and wet resistance of the improved soil increases with the increase of the amount of cement,while the compressive strength of the improved soil with small amount of cement decreases faster.