大断面公路隧道施工风流分布规律研究

为了采取有效的通风措施降低钻爆法施工的粉尘浓度，以辛庄隧道为例，通过对其掌子面附近风流的现场实测，系统的开展了风流流场分布规律的研究，并采用Fluent软件进行了数值模拟，模拟结果与实测数据基本吻合。结果表明:隧道内风流速度以风筒出口为界，分为射流扩张区、射流收缩区、涡流区、回流区4个部分；靠近掌子面的同一断面上:风速呈“中间小，两边大”的形式，且回流区面积稍大于射流区面积，其中射流区最大断面积约占整个断面积的40%。研究结果对隧道施工通风除尘具有一定的指导意义和使用价值。

Study on airflow distribution regularities in construction of large section highway tunnel

In order to take effective ventilation measures to reduce the dust concentration in construction by drilling and blasting method, taking the Xinzhuang tunnel as example, through the field measurement on the airflow around the tunnel face, the study on the distribution regularities of airflow field was conducted systematically. The numerical simulation was carried out by using Fluent software, and the simulating results were essentially coincident with the measured data. The results showed that: the airflow velocity in the tunnel was divided into four parts, including jet expansion zone, jet contraction zone, eddy zone and recirculation zone, which took the air duct outlet as boundary. On the same section near the tunnel face, the air velocity presented the form of "middle small, both sides big", and the area of recirculation zone is slightly greater than that of jet zone, among which the biggest sectional area in the jet zone accounted for about 40% of the whole sectional area. The results have a certain guiding significance and application value to the ventilation and dust removal in tunnel construction.