摘要
充填体早期力学性能对于缩短二步骤回采周期具有重要作用。借助爆破扰动试验装置对充填体进行爆破扰动模拟试验,测试充填体的应变、抗压强度,借助SEM扫描分析充填体的微观结构,研究了频繁爆破扰动对充填体早期力学性能的影响。研究结果表明:随着龄期增加,抗扰动能力增强,未施加轴向载荷下,横、竖向应变曲线不对称;充填体受冲击扰动后,抗压强度下降,随着养护时间增长,受扰充填体的抗压强度较未扰动充填体的增长大;冲击扰动可增大凝胶体表面积,提高均质度,使未水化胶凝材料颗粒与释放出的部分孔隙水、凝胶水发生水化学反应,生成水化产物填充孔隙,降低孔隙率,弥补损伤,提高受扰充填体的强度。
The early mechanical properties of backfill play an important role in shortening the two-step mining period.With the help of blasting disturbance test device,the simulation test of blasting disturbance was carried out to test the strain and compressive strength of the backfill.The microstructure of the filling body was analyzed by SEM scanning,and the influence of frequent blasting disturbance on the early mechanical properties of the backfill was studied.The results show that,with the increase of curing age,the ability of anti disturbance is enhanced.Under the condition of no axial load,the transverse and vertical strain curves are asymmetric.Under impact disturbance,the compressive strength of the backfill decreases,and the compressive strength of the impacted backfill is larger than that of the undisturbed backfill with the increase of curing time.The impact disturbance can increase the surface area of the gel,improve the homogeneity,and cause the hydration reaction of the unhydrated cementitious material particles with the partially released pore water and gel water,so as to form the hydration product for filling pores.Therefore,the porosity is reduced,the damage is recovered,and the strength of the disturbed backfill is enhanced.
作者
甘肃
郑怀昌
杨雷
李公成
王劼
GAN Su;ZHENG Huaichang;YANG Lei;LI Gongcheng;WANG Jie(School of Resources and Environment,Shandong University of Technology,Zibo,Shandong 255049,China)
出处
《矿业研究与开发》
CAS
北大核心
2021年第2期130-137,共8页
Mining Research and Development
基金
国家重点研发计划政府间国际科技创新合作专项项目(2018YFE0123000).
关键词
胶结充填体
爆破扰动
凝胶
强度
水化反应
Cemented backfill
Blasting disturbance
Gel
Strength
Hydration reaction
