真空预压法加固尾矿软泥现场试验研究

Field Tests of Reinforcing Fine Tailings With Vacuum Preloading Method

针对尾矿泥含水率高、强度低导致的铀尾矿库坝体稳定性差及覆盖层施工难度大等问题,开展了真空预压法联合塑料排水板加固尾矿泥现场试验,分析了在不同塑料排水板间距下尾矿泥地表沉降、分层沉降、侧向位移、固结度、孔隙水压力等参数的变化规律,并进行了现场十字板剪切试验及地基承载力试验。研究表明,真空预压法可加速尾矿泥脱水,有效降低尾矿泥含水率,提高尾矿泥强度及承载力,且排水板间距1.0 m时的加固效果较好。真空预压法成本低、效果好、安全环保,在尾矿泥原位脱水加固中具有广阔的应用前景。

In order to solve the problems of poor dam stability and difficult construction of cover system caused by high water content and low strength of fine tailings,a series of field tests of the vacuum preloading method combined with prefabricated vertical drains to reinforce fine tailings were carried out.The surface settlement,layered settlement,lateral displacement,degree of consolidation and pore water pressure of tailings under different spacing of prefabricated vertical drains were analyzed,and vane shear test and bearing capacity test of tailings were conducted.The research results show that vacuum preloading method can accelerate dewatering of tailings,effectively reduce the water content,then improve the strength and bearing capacity of tailings,and the reinforcement effect of prefabricated vertical drains spacing of 1.0 mis better than that of 1.2 m.As a technology with low cost,good effect,safety and environmental protection,vacuum preloading method has a broad application prospect in in-situ dewatering and reinforce of fine tailings.