水泥粉煤灰-改性水玻璃注浆材料试验研究与应用

Experiment study and application of cement fly ash-modified sodium silicate grouting material test

为解决传统注浆材料在大体积充填注浆时成本高、固废材料利用低、凝胶时间控制不精确等问题,提出水泥粉煤灰-改性水玻璃注浆材料。通过室内试验分析改性水玻璃配比、改性水玻璃体积分数和粉料比例对浆液初凝时间、终凝时间、流动度及单轴抗压强度的影响规律;通过工程现场试验,研究该注浆材料的可泵性、操作性,利用物理探测方法,对注浆治理效果进行评价。结果表明,水泥粉煤灰-改性水玻璃注浆材料的初凝时间为8~70 s、终凝时间为2~9 min;初凝时间随改性水玻璃体积分数的增加而增长,终凝时间随改性水玻璃体积分数的增加而缩短;凝胶时间与粉料中粉煤灰的质量分数呈正比;浆液流动度与改性水玻璃体积分数及粉料中粉煤灰质量分数成正比;粉煤灰质量分数与浆液结石体抗压强度呈负相关,改性水玻璃体积分数(水泥粉煤灰浆液与改性水玻璃体积之比)为1∶0.6或1∶0.4时,水泥粉煤灰-改性水玻璃注浆材料固结体的7 d抗压强度达到峰值9.35 MPa和6.86 MPa;水泥粉煤灰-改性水玻璃注浆材料可提高固废利用率,且各性能满足注浆需要,在实际应用中可依据工程要求调整配比,为类似的注浆工程提供参考。

In order to solve the problems of high cost,low utilization of solid waste material and inaccurate control of gel time when traditional grouting material were filled and grouted in large volumes,cement fly ash-modified sodium silicate grouting material was proposed.Through laboratory tests,the effects of modified sodium silicate ratio,modified sodium silicate volume content and pow-der ratio on the initial setting time,final setting time,fluidity and uniaxial compressive strength of slurry were analyzed.The pump-ability and maneuverability of the grouting material were studied through the field test of the actual project,and the treatment effect of the grouting was evaluated by using the physical detection method.The results showed that the initial setting time of cement fly ash-modified sodium silicate grouting material was 8-70 s and the final setting time was 2-9 min.The initial setting time increased and the final setting time decreased with the increase of the volume content of modified sodium silicate.The gelation time was pro-portional to the content of fly ash in the powder.The fluidity of slurry was proportional to the content of modified sodium silicate and fly ash in powder.The content of fly ash was negatively correlated with the compressive strength of the grout stone body.When the volume content of modified sodium silicate was 1∶0.6 or 1∶0.4(the volume ratio of cement fly ash slurry to modified sodium sili-cate),the compressive strength of the cement fly ash-modified sodium silicate grouting material consolidation body in 7 d reached the peak value of 9.35 MPa and 6.86 MPa.Cement fly ash-modified sodium silicate grouting material could improve the utilization rate of solid waste,and each performance could meet the needs of grouting,in practical application could be adjusted according to the requirements of the project,to provide a reference for similar grouting projects.