高阶段胶结充填体强度的变化规律

根据企业降本增效要求，矿山使用的充填胶结材料由原来的P.C32.5标号水泥改为新型胶结材料--胶固粉。按照设计要求的充填配比，发现地表实验室料浆试块和井下充填体取芯的强度存在很大差异。在-400 m中段的14-1#和10-3#充填采场中，提取不同深度的地表实验室和井下充填体的岩芯，分析2种胶结材料在不同养护条件下所对应的强度变化规律。对于水泥充填的采场，充填体取芯的强度要比实验室试块的强度高1.8 MPa以上；对于胶固粉充填的采场，灰砂比分别为1∶4、1∶5、1∶6时充填体取芯的强度要比实验室试块强度高2.0、1.35和0.7 MPa以上，且随着充填灰砂比的降低而降低。研究结果为进一步优化充填灰砂比提供了可靠的依据，进而可减少充填材料的消耗，降低充填成本。

Change Laws of the Strength of High Level Cemented Backfill Body

The cemented material，P.C32.5 cement，that was previously used in the mine is replaced by a new cementing material，named cementation powder，according to the requirement of lowering costs and improving efficiency.Based on the filling ratio required in design，there was a great difference between the blocks strength in the surface laboratory test and the core strength at filling body.At the stopes of 14-1# and 10-3# at the -400 m stage，the strength of blocks at surface laboratory and underground core at different depth was extracted，and the change law of strength for two kinds of cementing materials in different curing conditions was analyzed.For cement filling stope，the underground core strength was above 1.8 MPa higher than that of blocks in the laboratory test;For glue powder filling stope，the underground core strength at the three ratio（1∶4,1∶5,1∶6）was respectively above 2.0 MPa and 1.35 MPa and 0.7 MPa higher than that of blocks in the laboratory test，and with the decrease of the ratio，the filling strength was reduced.It provides a reliable basis for further optimizing the cement-sand ratio and thereby reducing the material consumption and filling cost.