玻璃纤维增强水泥基尾砂胶结充填体力学性能试验研究  

Experimental Study on Mechanical Properties of Glass Fiber Reinforced Cement-Based Tailings Cemented Backfill

作　　者：石静[1] 王强[2] SHI Jing;WANG Qiang(Academy of Civil Engineering&Architectural,Nanyang Normal University,Nanyang,Henan 473061,China;College of Hydraulic and Civil Engineering,Zhengzhou University,Zhengzhou,Henan 450001,China)

机构地区：[1]南阳师范学院土木建筑工程学院,河南南阳市473061 [2]郑州大学水利与土木工程学院,河南郑州450001

出　　处：《矿业研究与开发》2022年第10期51-57,共7页Mining Research and Development

基　　金：国家自然科学基金项目(52078468).

摘　　要：针对山东烟台某金矿充填体强度低、稳定性差等问题,选用高炉矿渣、钢渣、脱硫石膏等工业固体废弃物制备胶凝材料,掺入玻璃纤维作为加筋材料以改善充填体力学性能。首先,分析充填材料的物理化学性质,然后,开展正交试验,探究纤维掺量、纤维长度和钢渣掺量对水泥基尾砂胶结充填体抗压强度、抗折强度和劈裂抗拉强度的影响。研究结果表明:随着纤维掺量的增加,充填体力学性能表现为先增加后降低的趋势,当纤维掺量为0.5%时,充填体抗压强度和抗拉强度达到最大值,当纤维掺量为0.3%时,充填体抗折强度改善效果最好;随着纤维长度的增加,充填体抗折强度和抗拉强度逐渐增大,充填体抗压强度先增加后降低,在纤维长度为6mm时,抗压强度达到最大值;适量的纤维掺入弥补了充填体内部结构的缺陷,抑制了裂缝扩展,增加了致密度,使充填体力学性能不断上升,但过量掺入会导致纤维相互缠结形成应力集中区,削减了充填体力学性能。钢渣掺量为10%时,充填体力学性能最优,继续增加钢渣掺量,胶凝体系中用于支撑充填体宏观强度的水化产物钙矾石、C—S(A)—H凝胶、Ca(OH)_(2)的生成量减少,充填体试件难以抵抗较大的荷载,充填体力学性能降低。To address the problems of low strength and poor stability of the backfill in a gold mine in Yantai,Shandong Province,industrial solid wastes such as blast furnace slag,steel slag and desulfurization gypsum were selected to prepare cementitious materials,and glass fiber was added as reinforcing material to improve the mechanical properties of the backfill.First,the physical and chemical properties of the filling materials were analyzed,and then orthogonal tests were conducted to investigate the effects of fiber dosage,fiber length and steel slag dosage on the compressive strength,flexural strength and splitting tensile strength of cement-based tailings cemented backfill.The results show that with the increase of fiber dosage,the mechanical properties of backfill show a trend of increasing first and then decreasing,the compressive strength and tensile strength of the backfill reach to the maximum value when the fiber dosage is 0.5%,and the flexural strength of the backfill has the best improvement effect when the fiber dosage is 0.3%.With the increase of fiber length,the flexural strength and tensile strength of the backfill gradually increase,the compressive strength reaches to the maximum value when the fiber length is 6 mm.The appropriate amount of fibers mixed into the backfill makes up for the internal structural defects,inhibits the crack expansion,increases the dense density,and makes the mechanical properties of the backfill rise.However,excessive addition of fiber will lead to mutual entanglement of fibers to form a stress concentration zone,reducing the mechanical properties of the backfill.The mechanical properties of the backfill are optimal when the steel slag dosage is 10%.If the steel slag dosage continues to increase,the generation of the hydration products calcium alumina,C—S(A)—H gel and Ca(OH)used to support the macroscopic strength of the backfill in the cementation system decreases,the backfill specimens hardly resist large loads,and the mechanical properties of the backfill decrease.

关 键 词：尾砂胶结充填体 钢渣 玻璃纤维 正交试验 力学性能 

分 类 号：TD853.34[矿业工程—金属矿开采]