Analysis and Evaluation of Wastewater Quality During Tunnel Construction Based on Drilling and Blasting Method

Abstract

During the construction of tunnel based on drilling and blasting method, a large amount of wastewater will be produced, in which the types and concentrations of main pollutants will change regularly with the continuous circulation of construction process. In this paper, the wastewater of Hengwu tunnel in the drilling, post blasting, slag discharge and initial support stages is sampled and detected, the main pollutant types and change laws of construction wastewater in each stage are analyzed, and the set pair analysis method is used to evaluate the wastewater quality to determine the degree of wastewater pollution in different construction stages. The research shows that after blasting, the concentration of ammonia nitrogen first reaches the peak, and then other pollution concentrations begin to rise. Different construction stages have different effects on wastewater quality. The construction wastewater generated in the initial support stage of Hengwu tunnel is the most polluted, and the construction wastewater in the drilling stage is the least polluted. The research results of this paper can provide reference for the selection of wastewater treatment process in different construction stages of similar projects.