全尾砂胶结充填体的强度敏感性及破坏机制

以大冶铁矿全尾砂为原材料，采用水泥为胶结材料制作全尾砂胶结充填体，采用单因素五水平设计试验，研究了全尾砂胶结充填体强度与料浆中固相质量分数、灰砂配比及龄期之间的关系，并对敏感性进行了分析.胶结充填体强度随着料浆中固相质量分数的增加遵循指数函数增长，随灰砂配比的增加呈线性增长，随龄期增加遵循指数函数的增长，其中胶结充填体强度对龄期的敏感性最高，料浆中固相质量分数次之，灰砂配比最弱.胶结充填体抗压破坏试验结果显示，充填体的破坏经历了四个阶段，分别为微裂隙闭合阶段、线弹性阶段、微裂纹扩展阶段及裂纹贯通破坏阶段. 

Strength sensitivity and failure mechanism of full tailings cemented backfills

Full tailings cemented backfills were produced by taking Daye iron ore tailings as a raw material and cement as a cementing material. The relations of the backfills' strength with slurry concentration, sand-to-lime mass ratio and curing period, together with the sensitivity of the backfills' strength to these influencing factors, were studied by using single-factor five-level experiment design. The strength of the backfills follows an exponential function with slurry concentration and curing period, but a linear function with sand-to-lime mass ratio. Moreover, the sensitivity of the backfills' strength to curing period is the highest, but is the weakest to sand-to-lime mass ratio. Compressive failure test results show that destruction of the backfills goes through four stages, including micro-crack closure stage, linear elastic stage, micro-crack propagation stage, and crack coalescence stage.