矸石基含水层注浆改造新型材料实验与应用

高承压灰岩含水层上煤炭开采,经常需要对强含水层进行注浆改造,因含水层发育规模巨大,注浆材料用量动辄数万吨。在充分利用地下工程址区厂矿企业固体废弃物煤矸石基础上,研发了一种适用于含水层改造的新型无机注浆材料。通过组分筛选试验、力学性质测定试验、获取了材料的抗折强度、抗压强度、渗透系数等宏观力学性能;采用SEM微观分析手段,分析了注浆结石体的微观结构性能。综合力学性能、经济因素、环境效益,对比了新型材料与常规注浆材料的适用性。结合现场试验,验证了新型注浆材料的效果。研究结果表明:在水泥含量为35%时,新型注浆材料的早期强度与后期强度均高于水泥含量为40%时水泥-黏土浆液的同期强度。材料的最佳配合比为水泥30%,黏土10%,煤矸石60%。该材料体系结石体28 d抗压强度3.4 MPa,28 d抗折强度1.7 MPa,渗透系数1.794×10-7m/s,能够满足含水层改造需求,对类似工程具有借鉴作用。

Experiment and application of new material for grouting of gangue based aquifer

Coal mining in the aquifer with high bearing pressure often needs to carry out the transformation to the strong aquifer.Tens of thousands of tons of grouting material are used because of the large scale of aquifer.Based on the modification mechanism of inorganic composite,a new type of inorganic grouting material is developed by using solid waste in mine and thermal power plant.The optimum mixture ratio of new material system is obtained by the laboratory test.The flexural strength,compressive strength,permeability coefficient of different composi-tions are tested,combining with the grouting engineering to select ratio.The microscopic structural performance of grouting stone body is tested by the micro analysis means of XRD and SEM.The mechanical properties,economic factors and environmental benefits are compared,and the applicability of the new materials and conventional grouting materials is compared.The results show that the cement content is 35%,the early strength and later strength of the new grouting material are higher than that of the cement clay slurry at the same time when the cement content is 40%.The cement content is 30%,the clay content is 10%,the coal gangue content is 60%,with appropriate content water reducing agent and accelerator.As for composite material stone body (28 d),the com-pression strength is 3.4 MPa,the flexural strength is 1.7 MPa,and the permeability coefficient is 1.794×10-7 m/s.The results meet the requirements of aquifer grouting reconstruction,which is expected to offer some reference to similar projects.