CAJ | 학술논문

针对直接法瓦斯压力测定过程中受承压水影响的问题进行分析研究，通过查阅国内外文献发现，目前含水煤岩层瓦斯压力测定过程中，考虑煤层透气性系数、吸附特性的水锥效应尚未有人研究。针对此建立了动态水锥突破钻孔界限理论模型，分析认为瓦斯压力测定过程中放空时瓦斯流量最大，水锥突破速度最快，封孔后气体流量减少后影响变小。推导出了动态水锥上升过程中突破钻孔界限的时间与瓦斯流量、煤层厚度、钻孔深度及煤的孔隙率的关系式。并举例计算了不同流量、煤层厚度及钻孔长度下水锥突破界限的时间，发现，突破时间随流量的增大显著减小，流量一定时，随钻孔深度的增加，先经历一个变化较小过程，然后大幅度减小。工程上利用球向流场进行瓦斯压力时，可以通过缩短放空时间避免煤层水锥效应对测压的影响。
침대직접법와사압력측정과정중수승압수영향적문제진행분석연구，통과사열국내외문헌발현，목전함수매암층와사압력측정과정중，고필매층투기성계수、흡부특성적수추효응상미유인연구。침대차건립료동태수추돌파찬공계한이론모형，분석인위와사압력측정과정중방공시와사류량최대，수추돌파속도최쾌，봉공후기체류량감소후영향변소。추도출료동태수추상승과정중돌파찬공계한적시간여와사류량、매층후도、찬공심도급매적공극솔적관계식。병거례계산료불동류량、매층후도급찬공장도하수추돌파계한적시간，발현，돌파시간수류량적증대현저감소，류량일정시，수찬공심도적증가，선경력일개변화교소과정，연후대폭도감소。공정상이용구향류장진행와사압력시，가이통과축단방공시간피면매층수추효응대측압적영향。
The water coning of coal seam permeability coefficient and adsorption characteristic has seldom been studied at home and abroad. Aiming at that, the theory model of dynamical water coning breaking through boundary of drilling hole was established. The analysis presents that when evacuation during the process of gas pressure determination, gas flow amount is maximum, breaking through ve-locity of water coining is fastest, and the influence of gas flow decreasing after borehole sealing is smaller. Additionally, the relation between the time of breaking through boundary of drilling hole and the gas flow amount, thickness of coal seam, drilling depth and the porosity of coal mass in the rising process of dynamic water coning has been derived, and the times of water coning breaking through the boundaries with different flow rate, coal seam thickness and length of borehole were calculated. It is found that the breaking through time greatly reduces with the increase of flow rate. As the flow rate keep a constant, with the increase of the drilling depth, the breaking through time first undergoes a smaller variation process, and then decreases significantly. Moreover, using the ball direction flow field to determine the gas pressure in engineering , the influence of coal seam water coning to the gas pres-sure determination can be avoided by shorten the evacuation time.