模袋性能的试验研究与模袋法尾矿坝稳定性分析

Experimental Research about Geofabriform and Stability Analysis of Tailings Dam Using Soil Geofabriform

采用与施工现场一样的土工布和尾砂,对固结不同天数的模袋体进行了摩擦性能和受压性能的试验研究。在摩擦性能试验中,先是通过一种简单的室内斜坡滑移试验研究了不同固结天数的模袋体之间的摩擦性能。之后,为研究模袋体在受载作用下的摩擦性能,又对模袋体进行了直剪试验。摩擦性能试验结果表明:固结天数越长,含水率越少,模袋体之间的摩擦系数越大;对于相同固结天数的模袋体,两种试验方法测得的摩擦系数相差不大。在模袋的受压性能试验中,对单个模袋体进行单轴压缩试验,主要研究了不同含水率的单个模袋体的极限承载力。试验结果表明:在缓慢加载的条件下,虽然模袋固结度不同,但最后其极限承载力相差不大。最后,依据极限平衡理论讨论,提出了一种适合分析模袋法尾矿坝整体稳定性的计算方法;并对模袋法尾矿坝整体稳定性的相关问题进行了讨论。分析结果表明,对于容易发生浅层滑动的坝体而言,模袋法尾矿坝较常规尾矿坝有更好的稳定性。

The friction performance and compression property about geo-fabriform of different degree of consolidation were researched by means ofslope sliding test,direct shear test and pressure test. The geofabriform is made up with geotextile and tailings sands,which both come from a construction site in Yunnan province. Slope sliding test is an easier method to study the friction performance about geofabriformof different degree of consolidation.Though the test,the friction coefficient was obtained between geofabriform and the following result： the greater the degree of consolidation,the less moisture content,the friction coefficient between geofabriformis larger. Given the geofabriform to withstand vertical loadin the practical engineering,the direct shear test was proposed and conducted. Theultimate bearing capacity of geofabriformof different consolidation degree was studied in the uniaxial compression test. The testshowed theultimate bearing capacity of geofabriform,which had different moisture contentbefore the test,is almost the same under the condition of slow loading. Finally,a stability analysis methodbased on limit equilibrium theory was developed to simulate the stability of tailings dam using soil geofabriform. The results show,for the shallow sliding of the dam,slide tailings dam using soil geofabriform has a better stabilitycompared with general tailingsdam.