一种新型带压注浆封孔测压技术的密封效果研究

Study on Sealing Effect of a New Pressurized Grouting and Hole-sealing Gas Pressure Determination Technology

为了提高煤层瓦斯压力测定的准确性,解决传统封孔测压方式易发生喷浆及密封性差的问题,基于对测压失效原因的分析,提出一种新型带压注浆封孔测压技术。通过建立力学平衡方程研究了新型封孔测压技术装置承压密封效果,利用COMSOL模拟分析了带压注浆后浆液扩散模型。分析结果表明:新型封孔测压技术比传统测压方式有更好的承压能力,可为带压注浆提供保障;以4 MPa浆压、带压注浆12 h可以使浆液达到最佳扩散效果,能较好地封堵钻孔裂隙圈。通过现场对比试验,结果表明新型封孔测压技术比传统常压注浆封孔测压技术测压结果更准确,测压时间更短。

In order to improve the accuracy of coal seam gas pressure measurement and solve the problems that the traditional hole-sealing pressure measurement method is liable to spray and has poor tightness,a new type of pressure measurement technology by pressurized grouting and hole sealing was proposed based on the cause analysis of failure pressure measurement. The bearing effect of the device of the pressure measurement technology by pressurized grouting and hole sealing was studied by building a mechanical equilibrium equation,and the slurry diffusion model after pressurized grouting was analyzed by COMSOL simulation. The analysis results showed that the new hole-sealing pressure measurement technology had better bearing capacity than the traditional one,which can provide guarantee for the implementation of the pressurized grouting;the slurry can reach the optimum diffusion effect when the pressurized grouting was continuously done for 12 h at the pressure of4 MPa and the fissures around the borehole can be better sealed. The field tests testified that the new hole-sealing pressure measurement technology was more accurate and its pressure measurement time was shorter as compared to the traditional constantpressure grouting hole-sealing technology.