China Safety Science Journal ›› 2024, Vol. 34 ›› Issue (S1): 72-78.doi: 10.16265/j.cnki.issn1003-3033.2024.S1.0029

• Safety engineering technology • Previous Articles     Next Articles

Dust migration characteristics of mixed ventilation in drainage corridor constructed by TBM method

HE Shaoyun1(), LIU Xiaoxuan1, WU Xiaolin1, WANG Fuli2, TANG Xiao1   

  1. 1 Zhejiang Jinyun Pumped Storage Power Co., Ltd., Jinyun Zhejiang 321400, China
    2 China Railway Engineering Equipment Group Technical Service Co., Ltd., Zhengzhou Henan 450016, China
  • Received:2024-01-12 Revised:2024-05-15 Online:2024-06-30 Published:2024-12-30

Abstract:

In order to solve the problems of serious dust accumulation and insignificant effect of ventilation and dust removal during the construction by full-section hard rock TBM method in the drainage corridor, the construction project of the drainage corridor of Jinyun Pumped Storage Power Station in Zhejiang Province was studied. Firstly, a three-dimensional model of the drainage corridor was established and meshed. Through mixed ventilation, the numerical simulation software Fluent was used to study the migration characteristics of airflow and dust. Then, by taking the three ventilation parameters of the distance between the dust removal air duct and the tunnel face, the distance between the ventilation air duct and the tunnel face, and the wind speed and pumping pressure ratio of the double duct as variables, the influence of the three parameters on the dust removal effect was explored respectively, and the three ventilation parameters were optimized. Finally, three preferred values were taken as the preferred scheme for field measurement to verify the dust removal effect of the scheme. The results show that the tunnel airflow presents different regions such as the jet zone, vortex zone, and recirculation zone. Dust diffusion is serious when forced ventilation (single ventilation duct) is adopted for energy saving. With the increase in the distance between the dust removal air duct and the ventilation air duct from the tunnel face, the dust mass concentration decreases first and then increases, and when the respective distances are 10 m and 12 m, the dust removal effect is better. When the pumping pressure ratio is 2, the dust removal effect is further improved. Compared with the original ventilation scheme, the optimized scheme achieves an average dust reduction rate of more than 95%, and the dust mass concentration in the staff concentration area is reduced to less than 2 mg/m3, which meets the relevant standards.

Key words: tunnel boring machine (TBM) method, drainage corridor, mixed ventilation, dust, numerical simulation

CLC Number: