膨胀性凝灰岩稳定性控制实验研究

发布时间：2018-04-01 02:38

本文选题：膨胀性凝灰岩　切入点：CPAM　出处：《长沙理工大学》2014年硕士论文

【摘要】：云南澜沧铅矿矿区断层褶皱发育,地层中多含膨胀性凝灰岩。凝灰岩中含有大量的粘土矿物,遇水膨胀,易软化崩解,是一种带有特殊工程特性的软岩。对于此类岩体的防治,常采用改性剂对粘土矿物进行改性,防止其水化膨胀,同时采用锚喷网支护的方法提高围岩的稳定性能。但一般的粘土改性剂都是小分子量的,多用于石油助剂,对于矿山膨胀性围岩的防渗堵水研究较少,且小分子量的粘土改性剂对于大孔隙的膨胀岩体填充封堵效果较差；又膨胀岩体因遭受周围环境的持续破坏,与支护措施之间失去稳定联接,如此支护措施往往起不到应有的效果。基于此,本文创造性的提出采用高分子量的阳离子型聚丙烯酰胺(简称CPAM),针对澜沧铅矿膨胀性凝灰岩进行改性,同时采用CPAM+水泥复合浆对其进行注浆加固,提高岩体整体稳定性能。本文通过实验验证与理论分析,取得了如下主要研究成果：1通过自由膨胀率实验与凝灰岩崩解物级配实验发现,CPAM改性液相较其他粘土改性剂而言,具有更为稳定、持久、优良的抑膨性能。CPAM改性液中的凝灰岩基本不膨胀崩解,最佳抑膨浓度为0.08%。2对不同浓度、不同温度下的CPAM溶液粘度进行了测定分析,得出CPAM浆液粘度与浓度之间近似成对数关系,受浓度影响很大,受温度影响小的结论。并对CPAM浆液粘度与浓度和温度之间的关系进行了数值拟合。3通过复合浆试块的点荷载实验,得出CPAM溶液浓度为0.06%,水灰比为0.45的复合浆试块抗压强度最高,相对无改性剂的水泥净浆试块提强33.7%。4模拟工程实际,自制模拟注浆仪,并对凝灰岩样品进行了模拟化学注浆。采用微距拍摄、扫描电镜与能谱分析相结合的方法,对注浆后试块的扩散效果进行了实验分析,结果表明CPAM改性液可注性良好、浆液扩散较充分,且对于本实验材料而言,无围压模拟注浆的适宜压强为0.6MPa。同时,对注浆后试块进行了点荷载实验,结果表明CPAM水溶液不仅不会对凝灰岩的强度造成损伤,反而有小量的提升。5针对澜沧铅矿巷道失稳问题提出了有针对性的稳定性控制方案,集中表现为“控水”和“补强”两种手段,并对常规注浆管进行了改进。
[Abstract]:The fault folds are developed in Lancang lead ore area of Yunnan Province, and there are many expansive tuff in strata. Tuff contains a lot of clay minerals. It is a kind of soft rock with special engineering characteristics because of water swelling, easy to soften and disintegrate, so it is a kind of soft rock with special engineering characteristics. The modifier is often used to modify clay minerals to prevent hydration and expansion, and to improve the stability of surrounding rock by bolting and shotcreting mesh. However, the common clay modifiers are small molecular weight and are mostly used as petroleum auxiliaries. There are few researches on seepage and water plugging of expansive rock mass in mine, and the small molecular weight clay modifier has poor effect on filling and plugging of expansive rock mass with large pores, and expansive rock mass is continuously destroyed by surrounding environment. The loss of a stable connection with the supporting measures, which often do not have the desired effect. In this paper, cationic polyacrylamide of high molecular weight (CPAM) is used to modify the expansive tuff of Lancang lead mine, and CPAM cement composite slurry is used to reinforce it. In this paper, through experimental verification and theoretical analysis, we have obtained the following main research results: 1. Through free expansion test and tuff disintegration gradation experiment, we find that CPAM modified liquid phase is better than other clay modifiers. The tuff in the modified solution of CPAM is stable, durable and stable. The viscosity of the CPAM solution with different concentration and temperature is determined and analyzed by the optimum inhibition concentration of 0.082.The swelling of the tuff in the modified solution is not collapsible. It is concluded that the relationship between viscosity and concentration of CPAM slurry is approximately logarithmic, which is greatly affected by the concentration. The relationship between the viscosity of CPAM slurry and the concentration and temperature was numerically fitted. 3. Through the point load experiment of the composite slurry, it was concluded that the compressive strength of the composite slurry was the highest when the concentration of CPAM solution was 0.06 and the ratio of water to cement was 0.45, and the results showed that the strength of the composite slurry was the highest when the concentration of CPAM solution was 0.06 and the ratio of water to cement was 0.45. Compared with the cement paste test block without modifier, the cement paste test block is strengthened 33.7.4 simulation engineering practice, self-made simulated grouting instrument, and the tuff sample was simulated by chemical grouting. The method of micro-shooting, scanning electron microscope and energy dispersive analysis was used. The experimental results show that the CPAM modified liquid has good injectability and sufficient slurry diffusion, and the suitable pressure for simulating grouting without confining pressure is 0.6 MPA for the material in this experiment. The point load experiments on the test blocks after grouting are carried out. The results show that CPAM aqueous solution not only does not damage the strength of tuff, but also has a small amount of lifting. 5. Aiming at the problem of roadway instability in Lancang lead Mine, a targeted stability control scheme is put forward. The two methods of "water control" and "reinforcement" are concentrated, and the conventional grouting pipe is improved.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU45

【参考文献】