硫酸盐渍土击实性能及影响因素试验研究

为了全面地揭示硫酸盐渍土击实性能的变化原因和规律，对不同条件下配制的硫酸盐渍土进行了一系列的轻型击实试验。试验研究表明，含盐量对硫酸盐渍土最大干密度和最优含水率的影响规律并不是单一不变的，它取决于土中硫酸钠的3种状态（硫酸钠溶液、无水硫酸钠和十水硫酸钠）及3种状态间的相对含量。硫酸盐渍土的最大干密度和最优含水率与土中不同状态硫酸钠相对含量间的关系曲线具有反相关性。闷料时间和初始含水率对硫酸盐渍土击实性能的影响与含盐量有关，当含盐量较低（如1.5%）时，其影响甚小；当含盐量较高（如5.0%）时，其影响显著。硫酸盐渍土在由湿到干的过程中会出现“假干现象”。该试验结果对工程中硫酸盐渍土的击实性能和压实度的合理评价都具有重要的参考价值。

An experimental study of the compaction characteristics of sulfate saline soil

To explore the mechanisms underlying the compaction performance of sulfate saline soil, a series of light compaction tests is conducted on sulfate saline soils under various mixing conditions. The testing results show that the effect of salt content on the maximum dry density and the optimum moisture content of sulfate saline soil is complex; and it depends on the three states of sodium sulfate (sodium sulfate solution, anhydrous sodium sulfate and sodium sulfate decahydrate) and the relative amount of these three states of sodium sulfate. Both the maximum dry density and the optimum moisture content are inversely correlated to the relative amount of different states of sodium sulfate in the soil. The effects of the original moisture content and the curing times on the compaction are related to the salt content. The effect is trivial when the salt content is low (e.g. 1.5%), and very significant when the salt content is high (e.g. 5.0%). During the drying process, sulfate saline soil shows a false drying phenomenon. These experimental results provide a reference for evaluating the compaction characteristics and the degree of compaction of sulfate saline soils.