赤泥-水泥复合土的工程特性试验研究

Experimental study on engineering properties of red mud-cement composite soil

为探究赤泥对水泥复合土的无侧限抗压强度、抗冻性能和疲劳特性的影响,借助扫描电镜观察了试件微观结构,利用能谱仪对试件内部元素成分的变化规律进行了机理分析.结果表明:在相同冻融循环次数条件下,当水泥掺量为12%时,赤泥-水泥复合土无侧限抗压强度随赤泥掺量的增加呈先上升后下降的趋势,赤泥掺量为16%时达到峰值,而当水泥掺量为20%时,赤泥-水泥复合土无侧限抗压强度随赤泥掺量大体呈线性增长关系;赤泥-水泥复合土无侧限抗压强度随疲劳次数、加载频率的增加整体呈下降趋势,但加载频率影响程度相对较小.试件微观结构与元素成分变化表明,赤泥掺量的增加能够有效增强颗粒物之间黏结强度,提高骨架致密程度.

In order to explore the effect of red mud on the unconfined compressive strength,frost resistance and fatigue properties of cement composite soil,the microstructure of the specimen was observed by means of scanning electron microscope,and the change rule of element composition inside the specimen was investigated by energy dispersive spectrometer.The results show that under the same number of freeze-thaw cycles,when the cement content is 12%,the unconfined compressive strength of the red mud-cement composite soil increases first and then decreases with the increase of the red mud content.When the content of red mud is 16%,the peak value is reached,and when the content of cement is 20%,the unconfined compressive strength of red mud-cement composite soil increases linearly with the content of red mud.The uncondined compressive strength of red mud cement composite soil decreases with the increase of fatigue times and loading frequency,but the effect of loading frequency is relatively small.The changes of the microstructure and element composition of the specimens show that the increase of the red mud content can effectively enhance the bonding strength between particles and improve the density of the skeleton.