针对某铁矿的充填胶凝材料选择和配比参数设计，开展了全尾砂胶固粉胶结充填体与水泥胶结充填体的强度对比试验。先考察全尾砂的基本物理力学特性，并在此基础上采用全面试验法设计试验，测试了不同灰砂比、不同质量浓度全尾砂充填体试块单轴抗压强度。结果显示：该铁矿山全尾砂的加权平均粒径为dav＝0.21 mm，大于0.074 mm的尾砂占53.82％，全尾砂较粗；灰砂比1∶10、浓度70％、28 d养护龄期的水泥胶结试块抗压强度为1.13 MPa，相同条件下胶固粉胶结试块抗压强度是水泥胶结试块的2.33倍即2.63 MPa；胶固粉胶结试块强度平均是水泥胶结试块的2.93倍即2.79 MPa。水泥胶结试块不仅强度相对较低，而且增大灰砂比，其强度增长率小于胶固粉胶结试块；降低灰砂比，水泥胶结试块强度不稳定。以上结果表明胶固粉的胶结强度高，成本也低于水泥，是较优的胶凝材料。%For the selection of binders and the design of mix proportion of an iron mine,the comparison test of backfilling strength between cement and full-tailing glue-powder is conducted.The basic physical and mechanical properties of full tailings are firstly examined.Based on this,with the use of comprehensive tests,the uniaxial compressive strength experiment of the full-tailing filling samples in different gray-sand ratio and pulp density are analyzed.The results shows that weighted average grain size of full tailings dav is 0.21 mm,where the amount of grain size of larger than 0.074 mm accounts for 53.82%,so the full tailings are coarser.The uniaxial compressive strength of cement backfilling for 28d is 1.13 MPa,when the gray-sand ratio is 1 ∶10,pulp density is 70%;while that cemented by glue-powder is 2.63 MPa,2.33 times as much as that of the cement. The average strength ratio of glue-powder is 2.79 MPa,2.93 times as much as that of the cement.The cement backfilling has a relatively low strength,and also increase the gray-sand ratio.Its strength growth rate is less than that of glue-powder,mean-while its strength is not stable in a lower gray-sand ratio.The glue-powder has a higher strength and a lower cost,so it is the optimal binder.
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