Study On Smoke Exhaust Without Shaft And Fire Evacuation And Rescue In Super Long Tunnel

With the development of social economy,urban traffic has entered a stage of rapid development,and the existing traffic level can hardly meet people’s travel needs.Speeding up the construction of transportation in coastal areas has been put on the agenda,improving and enhancing the capacity of cross-sea transportation is imperative.For this reason,a large number of undersea tunnels have emerged at home and abroad,and ultra-long undersea tunnels have also come into being.However,due to the particularity of ultra-long undersea tunnel structure,it is difficult to discharge high-temperature smoke and toxic gas in case of fire,which will cause damage to tunnel structure and even injuries to personnel.Smoke exhaust and evacuation rescue have become key factors restricting the development of ultra-long undersea tunnel.In this paper,the study of smoke exhaust without shaft and evacuation rescue in ultra-long undersea tunnel will provide theoretical basis for the further development of ventilation and smoke exhaust technology in ultra-long undersea tunnel and the engineering design of personnel evacuation.Based on the general situation of Yanda undersea Tunnel project,this paper set up a smoke exhaust system without shaft between North Cheng-Huang Island and Lao-Tie Mountain Sea area.The research contents and conclusions are as follows:(1)A new type of undersea tunnel smoke exhaust technology is proposed,that is,smoke exhaust technology without shaft,and a smoke exhaust method without shaft is given.(2)Pyro Sim numerical simulation software was adopted to establish a tunnel model without a shaft smoke exhaust system,and the smoke layer thickness,smoke spread length,smoke exhaust efficiency and personnel evacuation environment under different fire source power,smoke exhaust volume and air supplement volume were studied to find the optimal smoke exhaust and air supplement volume.The results show that when the fire power is10MW and 12MW,the smoke output is 200m~3/s,the fire power is 15MW,the smoke output is 220m~3/s,the air supply accounts for 70%of the smoke output,the smoke exhaust effect is the best.(3)Pyro Sim numerical simulation software was used to establish a tunnel model without a shaft smoke exhaust system.When the fire source power was 10MW,the smoke exhaust volume was 200m~3/s,and the air conditioning volume was 70%of the smoke exhaust volume,the effects of the length,width,area and arrangement direction of the smoke exhaust outlet on the smoke layer morphology,smoke spread length and smoke exhaust efficiency were studied.The results show that the increase of the width of the exhaust port can improve the exhaust effect,while the length has no obvious influence on the exhaust effect.When the width of the exhaust port is 8m and the length is 3m,the exhaust effect of the exhaust system is the best.(4)Design the emergency rescue station,cross passage,emergency equipment and other evacuation rescue works,and give the emergency exit evacuation rescue plan with shaft,evacuation room evacuation rescue plan without shaft and random evacuation rescue plan,and give the corresponding air supply and smoke exhaust plan according to the fixed point and random evacuation rescue plan.At the same time,combined with the door wind speed method,the air supply volume of fixed point and random stop is obtained respectively.Combined with the evacuation rescue plan and the research results of smoke exhaust without shaft,the proposed smoke exhaust and air supply volume is given.