CAJ | 학술논문

通过数值模拟与现场实测对比,探寻冻结法隧洞施工中衬砌混凝土水化热温升与冻结壁温度场相互影响的规律。研究结果表明,在初期支护的钢拱架外部木背板及喷混凝土形成的保温层作用下,二次衬砌混凝土浇筑后水化热对冻结壁的影响深度仅有30~100 mm,只有表层冻土温度短时间内升至零度以上,而后迅速降到零度以下；虽然二次衬砌混凝土受到外部冻结壁低温影响,但混凝土内部温度仍能升至28℃以上,混凝土外表面温度在浇筑20 d后降至零度以下,表明混凝土强度增长基本不受影响。数值模拟与现场实测结果基本吻合,相关成果对类似工程研究及设计和施工有一定参考价值。
통과수치모의여현장실측대비,탐심동결법수동시공중츤체혼응토수화열온승여동결벽온도장상호영향적규률。연구결과표명,재초기지호적강공가외부목배판급분혼응토형성적보온층작용하,이차츤체혼응토요축후수화열대동결벽적영향심도부유30~100 mm,지유표층동토온도단시간내승지령도이상,이후신속강도령도이하；수연이차츤체혼응토수도외부동결벽저온영향,단혼응토내부온도잉능승지28℃이상,혼응토외표면온도재요축20 d후강지령도이하,표명혼응토강도증장기본불수영향。수치모의여현장실측결과기본문합,상관성과대유사공정연구급설계화시공유일정삼고개치。
For the tunnel construction using frozen construction method, we study the mutual influence of tunnel lining con-crete hydration heat and frozen wall temperature field by comparison of numerical simulation and field test. It is shown that in the initial supporting period, under the action of the heat-insulation layer formed by the wooden board outside the steel arch and the shotcrete, the influential depth of the hydration heat on frozen wall can only reach a superficial range of 30 to 100mm after the secondary concrete lining, only the temperature of surface frozen earth rise to above 0℃ in short time and drop to below zero soon after. Although the secondary lining concrete is influenced by the low temperature of the outside frozen wall, the internal tempera-ture of the concrete can rise to above 28℃, while the temperature of outer surface of the concrete drops to below zero in 20 days, which demonstrates that the increase of concrete strength is hardly affected. The results of numerical simulation are consistent with those of the field test.