Dust control performance of innovative arc device for metro system construction based on orthogonal experiment

Metro systems play a crucial role in enhancing the urban economy, but the serious dust pollution during its construction poses a significant threat to the health of workers. Widely used for dust control in metro systems, the current forced ventilation technology is characterized by low dust control efficiency. In this study, an innovative arc device with efficient dust control and convenient application was proposed based on the forced ventilation. Subsequently, the orthogonal experimental method was adopted to explore the effects of air supply outlet position (L), air supply volume (Q), and air supply mode (M) on the airflow-dust distribution characteristics. The results indicated that compared with the traditional forced ventilation, the application of arc device can shorten the safe entry time after blasting operations by 9.9%–32.1% within the air supply volume of 804–1876 m³/min, effectively improving the construction efficiency and reducing the construction costs. In other words, the arc device can achieve the same dust control requirements with a smaller air supply volume, which improves the engineering applicability of forced ventilation in long-distance tunnel excavation while reducing ventilation energy consumption. Furthermore, the theoretical optimal combination scheme (L = 35 m, Q = 1876 m³/min, M = arc device) composed of the optimal levels of three factors achieved a 13% improvement in dust control compared to the experimental optimal combination scheme determined by the minimum safe entry time. This study can provide new strategies for improving the dust control performance of forced ventilation used in metro system construction.