某特长铁路隧道斜井转正洞施工通风方式研究

Research on Ventilation Methods for the Construction of a Special Long Railway Tunnel with an Oblique Shaft Turning into a Main Tunnel

为研究铁路隧道施工通风的最佳方式,以某铁路隧道工程为依托,通过比较不同通风方式所需的风机功率及预计耗损电费选取最佳通风方式,同时利用Fluent软件对最佳通风方式进行数值计算,从而得出风流随距掌子面距离的运移规律。经过对通风方案的比选及数值计算,得出最佳通风方式为大功率串联压入式,其中3号斜井工区正洞段需要132×2kW的风机,4号斜井工区正洞段需要110×2kW的风机。3,4号斜井的斜井段和正洞段纵向风速变化规律均为先增大后减小最后趋于稳定,选取的风机型号可以满足通风需求。风带直径过大时会增加通风阻力,同时还会影响衬砌台车经过。考虑隧道实际施工情况,3号斜井工区斜井段风带直径选取1.8m,正洞段风带直径选取2m;4号斜井工区斜井段和正洞段风带直径均选取1.8m。

In order to study the optimal ventilation method for railway tunnel construction,this article takes one tunnel as a supporting project,selects the optimal ventilation method by comparing the required fan power and expected power consumption of different ventilation methods,and uses Fluent software to calculate the numerical value of the optimal ventilation scheme,thereby obtaining the migration law of air flow with the distance from the palm face.After comparing and calculating the ventilation schemes,it was found that the optimal ventilation method is the high-power series pressure type.Among them,No.3 oblique shaft work area requires 132×2kW power fan,No.4 oblique shaft work area requires 110×2kW power fan.The longitudinal wind speed changes in the oblique shaft section and the main tunnel section of No.3 and No.4 oblique shafts first increase,then decrease and finally stabilize.The selected fan model can meet the ventilation requirements.When the diameter of the wind belt is too large,it will increase ventilation resistance and also affect the passage of the lining trolley.Considering the actual construction situation of the tunnel,it is advisable to choose a wind belt diameter of 1.8m for the oblique shaft section of the No.3 oblique shaft work area,and a wind belt diameter of 2m for the main tunnel section.It is advisable to select a diameter of 1.8m for both the oblique shaft section and the main tunnel section of the No.4 oblique shaft work area.