CAJ | 학술논문

宁正煤田煤层上覆巨厚白垩系富水岩层，井筒多采用冻结法施工。由于对该岩层冻结温度场扩展特性以及冻结壁受水化热影响范围等缺乏研究，导致冻结设计不合理、冻结壁交圈时间预判不准确等问题。针对上述问题，以宁正煤田新庄煤矿风井为背景，通过现场实测和数值模拟，对该矿井白垩系砂岩地层冻结温度场扩展特性、外井壁混凝土水化热对冻结壁的影响开展了研究。实测结果表明：砂岩地层冻结初期温度快速下降，平均降温速率达0.23℃/d，冻结锋面的发展速率达21.08 mm/d；混凝土水化热对冻结壁温度场的影响大，冻结壁的融化深度范围为440~480 mm，距离外井壁50 mm的3#测点温度升高了33.6℃，平均升温速率达到了2.6℃/d。通过对数值模拟与实测结果比较发现：砂岩地层冻结壁扩展速度、井帮温度等参数值基本一致，能很好地预测冻结壁温度场变化规律。
저정매전매층상복거후백성계부수암층，정통다채용동결법시공。유우대해암층동결온도장확전특성이급동결벽수수화열영향범위등결핍연구，도치동결설계불합리、동결벽교권시간예판불준학등문제。침대상술문제，이저정매전신장매광풍정위배경，통과현장실측화수치모의，대해광정백성계사암지층동결온도장확전특성、외정벽혼응토수화열대동결벽적영향개전료연구。실측결과표명：사암지층동결초기온도쾌속하강，평균강온속솔체0.23℃/d，동결봉면적발전속솔체21.08 mm/d；혼응토수화열대동결벽온도장적영향대，동결벽적융화심도범위위440~480 mm，거리외정벽50 mm적3#측점온도승고료33.6℃，평균승온속솔체도료2.6℃/d。통과대수치모의여실측결과비교발현：사암지층동결벽확전속도、정방온도등삼수치기본일치，능흔호지예측동결벽온도장변화규률。
Because of very thick water-rich cretaceous strata covered on the seam of Ningzheng coal field, the freezing method is often applied to construct rockshaft. Due to the insufficient research on ex-tension features of the freezing temperature field and the range influence of the frozen wall caused by hydration heat, some problems will exist such as the unreasonable freezing design and the inaccurate time prediction for the closure of freezing wall. Based on the wind well of Xinzhuang mine in Ningzheng coal field, field measurement and numerical simulation have been carried out to study the characteristics of freezing temperature field distribution and influence of outer shaft wall concrete hy-dration heat. The results show as fellows:temperature falling fast at early freezing, the average rate of freezing can reach to 0.23℃/d;the development rate of freeze front reaches to 21.08 mm/d;the affect of concrete hydration heat on the temperature field of the frozen wall by side wall is serious, and the melting depth range of the frozen wall can reach 440-480 mm;the temperature of 3# measuring point from outer wall 50 mm rises 33.6 ℃ with the average heating rate achieving to 2.6 ℃/d. Results by comparing the numerical simulation and field test show that parameter values are basically identical,such as expansion rate of Sandstone freezing wall and well temperature, which can well predict the temperature field variation of frozen wall.