含盐量对松嫩平原碳酸盐渍土抗剪强度的影响

松嫩平原分布着大量的碳酸盐渍土,其不良的工程性质给穿越其中的道路质量造成不同程度的影响。由于盐渍土所含易溶盐成分主要为碳酸氢钠,该研究通过向碳酸盐渍土内加入碳酸氢钠制备不同含盐量的盐渍土,进行室内直剪试验。试验表明：随着含盐量的增加土的粘聚力减小,内摩擦角有先减小后变大的趋势;随着含水量的增加,土的含盐量越高,土的粘聚力减小越明显。易溶盐在土中的状态形式是影响其抗剪强度参数变化的一个重要原因。

Influence of salt content on shearing strength of the carbonate saline soil in Songnen (Songhuajiang River-Nenjiang River) Plain

Carbonate saline soil is widely distributed in the Songnen Plain, China. In the plain, the road quality is affected considerably by the saline soil because of its bad engineering properties. Chemical analysis showes that the major soluble salt in the saline soil is NaHCO3. Thus, this study makes soil samples of varied salt contents by adding NaHCO3 into the soil from the field, and carries out direct shear tests with the samples. The test indicates that the cohesion of the soil decreases with the increase of slat content; the friction angle of the soil firstly decreases and then increases with the increase of the salt content; the variance of the cohesion is more evident when the water content of the soil is high.