Study On Dust Transport Law And Control Technology Of Tunnel Blasting

With the rapid development of tunnel construction in China,the degree of construction mechanization has been gradually improved,the problem of excessive dust concentration in tunnel construction has become more and more serious,which poses a serious threat to construction safety and the health of workers.It is of great significance to study the transport law and control technology of dust in tunnel.However,at present,the research on dust transport law and its control technology is mostly focused on the mining industry,and the research on tunnel construction,especially tunnel blasting,is still relatively few.Therefore,this paper focuses on the dust transport law and its control technology after tunnel blasting.In this paper,theoretical analysis and numerical simulation are combined to carry out research.Firstly,the relevant theories of dust transport in tunnel construction are studied,the simulation method of gas-particle two-phase flow is determined and the corresponding governing equation is established.Then,taking a high-speed railway tunnel as the research object,the two-phase flow of air and dust in the tunnel is simulated by Fluent,the distribution characteristics of the airflow field in the tunnel and the dust transport law after blasting are obtained.Aiming at the problem that the efficiency of ventilation and dust discharge is low and will cause harm to the environment,remote spraying is used to settle the dust.The mechanism of liquid atomization,the mechanism of spray dust removal and the factors affecting the effect of spray dust removal are studied.Finally,the spray effect under different nozzle outlet wind speed,different nozzle pitch angle,different spray pressure and different nozzle diameter is simulated in Fluent,and the best spray parameters are determined,which could be a reference for the optimization of the remote spray dust removal system.