青藏铁路冻区盐渍土热特性及力学性能分析

Analysis of thermal characteristics and mechanical properties of salty soil in frozen area of Qinghai-Tibet Railway

路基冻胀、融沉是在青藏铁路经常遇到的现象,在盐渍土分布的冻区更为明显。运用TG-DSC技术对冻区盐渍土热特性进行分析并研究环境变化对冻土强度的影响,结果表明:易溶盐对盐渍土热特性有着重要影响,随含水率增大影响愈剧烈;冻结强度随着含水率的增大而增大,随冻结温度的降低而升高。所得结论对掌握青藏铁路盐渍土地区冻土工程冻胀、融沉特性有着指导意义。

The frost-heaving and thawing-settlement of roadbed are often met in Qinghai-Tibet Railway, especially in salty soil area. Thermal characteristics of salty soil are researched by TG-DSC technique. The results show that soluble salts have great influence on thermal characteristics of salty soil; water content gets higher, phenomena gets acuter. Freezing force depends on water content and freezing temperature; the more water content or the less temperature is, the more intensive of freezing force is. The conclusion has guiding significance for mastering the characteristics of frost heaving and thawing-settlement in salty soil area of Qinghai-Tibet Railway.