磷石膏物理力学性质的试验研究

Experimental Study on Physical and Mechanical Properties of Phosphogypsum

磷石膏是磷酸工业的废弃物,目前综合利用率不足40%,剩余部分堆积在磷石膏库内。为给磷石膏库的安全运营提供基础资料,对磷石膏开展了大量室内试验。结果表明:(1)磷石膏颗粒级配不良,按照粒径大小和稠度,它属于粉质黏土类;(2)磷石膏的渗透性随着干密度增大而降低,由中等渗透性逐渐转变为弱透水性;(3)磷石膏具有中等压缩性;(4)干密度提高后,三轴试验中磷石膏的剪切峰值应力有所提高,抗剪强度指标显著增大。

Phosphogypsum is a waste of the phosphoric acid industry.At present,the comprehensive utilization rate is less than 40%,and the rest is accumulated in the phosphogypsum stack.In order to provide basic information for the safety operation of the phosphogypsum stack,a large number of laboratory tests were developed.The results show that:(1)Phosphogypsum is bad gradation,and according to particle size and consistency,it belongs to silty clay;(2)The permeability of phosphogypsum decreases with the increase of dry density,and gradually changes from moderate permeability to weak permeability;(3)Phosphogypsum has moderate compressibility;(4)With the increase of dry density,the peak shear stress of phosphogypsum increases in the triaxial test,and the shear strength index increases significantly.