Abstract In sulfate-rich soils with high sodium sulfate contents, sulfate heave can occur and then generate severe damages to engineering facilities such as pavement, airplane runway due to the hydration of thenardite or crystallization of mirabilite when the temperature is below 32.4 °C. Based on the significant effect of expanded polystyrene (EPS) geofoam in reducing the temperature variations, a comparative experimental investigation on the sulfate heave of subgrade generated by the artificial coarse-grained saline soil with and without EPS material is conducted. Parameters of swell displacement and temperature fluctuation obtained from this comparative experiment are further validated and analyzed. The X-Ray Diffraction (XRD) measurement result is used to demonstrate the performance of EPS in microstructure. Test results indicate that: (1) The presence of crystallized mirabilite is proved within subgrade with saline soil when the temperature drops below 32.4 °C; (2) sulfate heave of subgrade is dependent on temperature fluctuation, but more specifically, on the temperature drop that occurs below 32.4 °C; and (3) EPS thermal insulation can reduce sulfate heave in pavement subgrade by effectively reducing the temperature fluctuation within the subgrade. Ce database subject headings Heave; Hydration; Salinity; Subgrades; Sulfates; Temperature effects.

中文翻译：

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用发泡聚苯乙烯（EPS）减轻路基硫酸盐隆起的保温隔热性能试验研究

摘要 在硫酸钠含量高的富含硫酸盐的土壤中，当温度低于32.4 ℃时，由于芒硝水化或芒硝结晶，会发生硫酸盐隆起，对路面、飞机跑道等工程设施造成严重破坏。基于发泡聚苯乙烯（EPS）土工泡沫在降低温度变化方面的显着效果，对人工粗粒盐渍土含EPS材料和不含EPS材料产生的路基硫酸盐隆起进行了对比试验研究。进一步验证和分析了从该对比实验中获得的膨胀位移和温度波动参数。X射线衍射（XRD）测量结果用于证明EPS在微观结构中的性能。测试结果表明：(1)当温度低于32.4℃时，盐渍土路基中证明存在结晶芒硝；(2) 路基硫酸盐隆起取决于温度波动，更具体地说，取决于发生在 32.4 °C 以下的温降；(3)EPS保温可以有效降低路基内的温度波动，减少路基中的硫酸盐隆起。Ce数据库主题词Heave；水合作用；盐度; 地基；硫酸盐；温度影响。(3)EPS保温可以有效降低路基内的温度波动，减少路基中的硫酸盐隆起。Ce数据库主题词Heave；水合作用；盐度; 地基；硫酸盐；温度影响。(3)EPS保温可以有效降低路基内的温度波动，减少路基中的硫酸盐隆起。Ce数据库主题词Heave；水合作用；盐度; 地基；硫酸盐；温度影响。