不同分散剂对膨胀土颗粒分析试验的影响

Effect of Different Dispersants on Particle Analysis Test of Expansive Soil

膨胀土是一种特殊性土,具有特殊的团粒结构,准确确定其粒组含量对于工程实践有重要意义。以南水北调工程中线南阳段膨胀土为研究对象,在分析其基本物理性质的基础上,通过密度计法对不同分散剂下的膨胀土进行颗粒分析试验,对比研究了分散剂类型对试验结果的影响。结果表明:采用六偏磷酸钠作为分散剂的分散效果较好,氨水的次之,氢氧化钠的分散效果最差。此结论明确了不同分散剂对同一试样的颗粒分析试验结果的影响,对于进一步认识和了解膨胀土的工程性质具有一定的意义。

Expansive soil is a kind of special soil with special aggregate structure, and it is of great significance for engineering practice to accurately determine the content of each grain group. In order to accurately determine the content of each grain group, the Nanyang expansive soil in the middle route of the South-to-North Water Transfer Project was taken as the research object. Based on the analysis of its basic physical properties, the particle analysis tests of expansive soils under different dispersants were carried out by hydrometer method, and the influence of every dispersant on the test results were compared. The test results show that the dispersing effect of sodium hexametaphosphate as dispersant is better, followed by ammonia, and the sodium hydroxide dispersing effect is the worst. This conclusion clarifies the influence of different dispersants on the particle analysis test results of the same sample, which has certain significance for further knowing and understanding the engineering properties of expansive soil.