强硫酸钠盐对饱和砂土动力特性影响的试验研究

Experimental Study on the Influence of Strong Sodium Sulfate on Dynamic Characteristics of Saturated Sand

为了研究强硫酸盐对饱和砂土动力特性的影响,配制五种不同工况饱和砂土试样。通过动三轴仪对试样土体进行动力特性试验,通过试验得到试样土体的应力曲线、应变曲线、动剪应力应变滞回曲线。结合ANSYS软件,模拟不同工况下饱和砂土的路基模型,分析其在地震荷载下Y轴的应力变化规律。结果表明:当土体达到液化时,含盐饱和砂土较不含盐饱和砂土所需振动次数更多;含盐饱和砂土中,10%含盐饱和砂土较其他三种土体达到液化时所需振动次数更多;当硫酸盐含量适当时,土体的动力特性高于普通砂土,而当硫酸盐含量继续增加时,土体的溶陷特性大于抗液化性能,土体刚度降低,抗液化性能降低。

In order to investigate the effect of strong sulfate on the dynamic characteristics of saturated sand,five saturated sand samples under different working conditions were prepared.The dynamic characteristics of the sample soil were tested by the dynamic triaxial apparatus,and the stress curve,strain curve and dynamic shear stress and strain hysteresis curve of the sample soil were obtained through the test.Comhined with ANSYS numerical simulation,the roadbed model of saturated sand under different working conditions was simulated,and the stress variation law of Y-axis under seismic load was analyzed.The results showed that when the soil reaches liquefaction,the vibration frequency of saturated sand with salt is higher than that of saturated sand without salt.In addition,10%saturated sand with salt requires more vibration times than the other three kinds of soil so as to achieve liquefaction.When the sulfate content is appropriate,the dynamic characteristics of the soil is higher than that of the ordinary sand,while when the sulfate content continues to increase,the dissolution characteristics of the soil is greater than the liquefaction resistance,and the soil stiffiiess decreases,so does the liquefaction resistance.