Traffic flow defibering time prediction method and system for tunnel fire emergency rescue efficiency toughness evaluation

Abstract

The invention provides a traffic flow defibering time prediction method and system for tunnel fire emergency rescue efficiency toughness evaluation, and the method comprises the following steps: building delayed traffic flow defibering processes, calculating the traffic flow densities KA, KB, KC and KD of each defibering process, and obtaining the traffic flows QA, QB, QC and QD of each defibering process; calculating the traffic flow wave of each defibering process according to the traffic flow density of each defibering process; calculating the tunnel fire vehicle defibering time TS (e); the method can calculate the traffic flow defibering time according to the tunnel parameters, can provide the traffic recovery time for real-time road traffic path planning when a fire accident occurs in the tunnel, and can also be used for evaluating the traffic flow defibering capability when the accident occurs in the tunnel. The tunnel parameters comprise design traffic volume, real-time operation traffic volume, speed limit, lane number, distance between an accident point and an upstream portal, and time before tunnel closing after an accident occurs.

Description

Technical Field

[0001] This invention relates to the field of tunnel fire emergency rescue technology, and specifically to a method and system for predicting traffic flow evacuation time for assessing the resilience of tunnel fire emergency rescue effectiveness. Background Technology

[0002] Tunnel fires are highly likely to cause significant casualties and property damage due to their enclosed spaces and difficult evacuation conditions. Timely and effective rescue can significantly reduce these risks.

[0003] After a fire breaks out in the tunnel, fire detectors, video event detectors, and closed-circuit television monitoring systems send fire alarm information. Upon receiving the fire alarm information, the tunnel control center or management station notifies the traffic police, fire department, and road administration units in sequence. Each rescue unit, after receiving the notification and confirming the basic information of the accident, immediately rushes to the scene. Upon receiving the fire rescue notification from the monitoring center, the tunnel management center's emergency rescue team immediately sounds the alarm and notifies the emergency rescue duty leader and team members to quickly deploy to the fire scene according to the command center's instructions.

[0004] After a fire breaks out, the control center will operate the variable message signs and lane indicators, activate the ventilation and smoke extraction system, and open the fire doors in the vehicle cross passages, such as... Figure 1 As shown, vehicles downstream of the accident point in the non-accident tunnel and the accident tunnel can quickly and normally exit the tunnel to complete the evacuation. Vehicles in the section upstream of the accident point in the accident tunnel to the entrance are divided into two groups. The first group, within a 2km radius upstream of the accident point, is a parking evacuation zone. Vehicles and occupants in this zone must immediately park on the right side and turn off their engines after the fire breaks out. Drivers and passengers in this evacuation zone upstream of the accident point should leave their keys inside the vehicle and evacuate to a safe area as quickly as possible following emergency broadcasts and evacuation signs. The second group, outside the 2km radius, is a non-parking evacuation zone. Vehicles in this zone should wait in place until all rescue vehicles arrive at the accident site before leaving the accident tunnel via the cross passage and exiting through the non-accident tunnel to complete the evacuation. Vehicles in the parking evacuation zone must wait until the fire is effectively controlled. Rescue personnel will guide occupants from the parking evacuation zone back to their original vehicles from a safe area before evacuation. The evacuation pattern is the same as for the non-parking evacuation zone: accident tunnel - cross passage - non-accident tunnel evacuation mode.

[0005] The tunnel fire emergency rescue efficiency is the condition and ability possessed by the tunnel fire scene to maximize the rescue efficiency and minimize the accident impact and consequences, and is a comprehensive embodiment of the timeliness and effectiveness of emergency rescue. The tunnel fire emergency rescue efficiency is composed of four dimensions of rescue unit arrival time, fire scale control, personnel safety guarantee and traffic impact degree control. Among them, the rescue arrival time is composed of the arrival time of the fire rescue unit and the management center rescue unit. The fire scale control factor can be mainly represented by the fire extinguishing completion time. The shorter the fire extinguishing completion time, the smaller the fire accident scale and consequences, and the better the fire scale control. The personnel safety guarantee needs to be based on the evacuation completion time within the available safe evacuation time range. Faster personnel evacuation can avoid major casualties. The traffic impact degree control mainly reduces the delay vehicle evacuation time in the accident area.

[0006] The traffic impact degree influence factor causal relationship feedback mechanism is shown in Figure 2 and Figure 3 , the tunnel fire traffic impact degree is mainly composed of three observation variables of the delay vehicle evacuation time in the accident area, the vehicle evacuation time downstream of the accident point in the accident tunnel and the vehicle evacuation time in the non-accident tunnel, wherein the vehicle evacuation time downstream of the accident point in the accident tunnel and the vehicle evacuation time in the non-accident tunnel are mainly determined by factors such as tunnel traffic volume and tunnel length. Because the delay vehicles upstream of the accident point need to wait for the arrival of the rescue unit and can start to evacuate only after the fire is effectively controlled, the fire extinguishing completion time and the personnel return to the original vehicle time directly affect the delay vehicle evacuation time in the accident area. In addition, because the delay vehicles in the upstream area of the accident point need to complete the evacuation through the vehicle cross passage, the lane changing and merging behavior of the vehicle flow is involved in this process. The greater the vehicle flow density in this area, the more the number of delay vehicles, and the longer the evacuation time required.

[0007] How to calculate the vehicle evacuation time calculation method is related to whether the tunnel fire emergency rescue efficiency resilience evaluation can be carried out. SUMMARY

[0008] The present application aims to provide a vehicle evacuation time prediction method for tunnel fire emergency rescue efficiency resilience evaluation. The technical scheme of the present application is: a prediction method for vehicle evacuation time for tunnel fire emergency rescue efficiency resilience evaluation, comprising the following steps:

[0009] S1. Establish the delay traffic flow evacuation process, calculate the vehicle flow density K A , K B , K C , K D of each evacuation process, and obtain the vehicle flow Q A , Q B , Q C , Q D of each evacuation process.

[0010] Before the tunnel fire occurs, the vehicles in the tunnel are in state A, the traffic volume in the tunnel is the real-time traffic volume, and the average speed is calculated based on the real-time traffic volume data according to a road resistance function;

[0011] After the tunnel fire occurs at time t0, the vehicles in the non-accident tunnel and the vehicles downstream of the accident point in the accident tunnel quickly drive out of the tunnel to complete the relief, and the vehicles in the interval from the accident point to the entrance in the accident tunnel are in a parking and waiting stage, and the vehicles in the tunnel are in state B, at this time, the vehicle speed and the traffic volume at the section of the accident point are both 0;

[0012] After time t1, the vehicles upstream of the accident point begin to relieve to the non-accident tunnel through the nearest vehicle running cross passage, and the traffic flow from the congestion queue upstream of the accident point to the vehicle running cross passage to the relief process in the non-accident tunnel is in state C;

[0013] After the first vehicle drives into the non-accident tunnel from the vehicle running cross passage at time t2, the traffic capacity is restored to the design traffic capacity, at this time, the vehicles in the tunnel are in state D, and the vehicle speed is restored to the speed limit;

[0014] S2. According to the vehicle flow density of each relief process, the vehicle flow wave of each relief process is calculated:

[0015]

[0016] ω AB is the vehicle flow wave of the relief process A-B state; ω BC is the vehicle flow wave of the relief process B-C state; ω CD is the vehicle flow wave of the relief process C-D state;

[0017] S3. The time T s of the vehicle flow relief upstream of the accident point of the tunnel fire to the non-accident tunnel is calculated.

[0018]

[0019] T1 is the time interval between the occurrence of the fire and the closure of the tunnel; L H represents the length of the vehicle running cross passage, V H represents the average speed of the vehicles passing through the vehicle running cross passage;

[0020] S4. The vehicle relief time T S(e) of the tunnel fire is calculated.

[0021] T S(e) =t e +T s

[0022] In the formula, t e represents the time of the personnel returning to the original vehicle.

[0023] The step S1 further comprises:

[0024] According to the traffic parameters under the tunnel fire scene, the total number of delayed vehicles N is calculated V and the traffic density K of the state A of the relief process n , the interval average speed V of the state A of the relief process A ;

[0025] N V = Q s ·t b + K A ·L d ;

[0026] Q s is the real-time operation traffic volume of the state A, t b is the time after the accident and before the tunnel is closed, and L d is the distance from the accident point to the upstream portal;

[0027]

[0028] V0 is the free running speed of social vehicles, which is taken as 80km / h; Q i is the actual traffic volume of the corresponding section, C i is the design traffic volume of the corresponding section, and i is the tunnel section;

[0029] The traffic density K of the state B of the relief process is calculated as follows:

[0030]

[0031] K B is the traffic density (veh / km) of the state B of the relief process; and L-L d is the distance from the accident point to the upstream portal;

[0032] The traffic density of the state C of the relief process is 105veh / km;

[0033] The traffic density of the state D of the relief process is the ratio of the design passing capacity to the speed limit.

[0034] t b = 2min.

[0035] When the number of lanes is greater than 2 and the section is a highway, α=0.390 and β=1.331; when the number of lanes is greater than 2 and the section is a general road, α=0.777 and β=1.897.

[0036] When the number of lanes is equal to 2 and the section is a highway, α=0.515 and β=1.569; when the number of lanes is equal to 2 and the section is a general road, α=1.287 and β=1.891.

[0037] A system for predicting the traffic flow dissipation time for tunnel fire emergency rescue efficiency and resilience assessment, comprising a memory, a processor and a computer program stored on the memory, the processor implementing the method for predicting the traffic flow dissipation time for tunnel fire emergency rescue efficiency and resilience assessment when executing the program.

[0038] The present application provides a method for predicting the traffic flow dissipation time for tunnel fire emergency rescue efficiency and resilience assessment, which can calculate the traffic flow dissipation time according to tunnel parameters. On the one hand, it can provide the traffic recovery time when a fire accident occurs in a tunnel for real-time highway traffic path planning. On the other hand, it can be used to evaluate the traffic flow dissipation capacity when an accident occurs in a tunnel. The tunnel parameters include design traffic volume, real-time operation traffic volume, speed limit, number of lanes, distance from the accident point to the upstream portal, and time before the tunnel is closed after the accident occurs. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 A dynamic model diagram for a tunnel fire emergency rescue efficiency system;

[0040] Figure 2 A schematic diagram of the internal causal relationship and dynamic mechanism of the traffic influence degree factor;

[0041] Figure 3 A diagram of the composition of the tunnel fire emergency rescue efficiency and resilience assessment index;

[0042] Figure 4 A diagram of the evolution mechanism of the delayed traffic flow dissipation process;

[0043] Figure 5 A schematic diagram of the traffic flow conservation equation;

[0044] Figure 6 A schematic diagram of the traffic flow wave formation and transmission process;

[0045] Figure 7 A schematic diagram of the traffic flow wave model for the traffic flow delay-dissipation process. DETAILED DESCRIPTION

[0046] The technical solutions of the present application are further described in conjunction with the drawings and examples.

[0047] Example 1

[0048] Please refer to Figure 1 The present application provides a method for predicting the traffic flow dissipation time for tunnel fire emergency rescue efficiency and resilience assessment, which comprises the following steps:

[0049] S1: According to the delayed traffic dissipation process, calculate the traffic density of each dissipation process

[0050] Establish the delayed traffic flow dissipation process:

[0051] like Figure 7 As shown, before the tunnel fire, vehicles inside the tunnel were in state A, with the traffic flow being the real-time traffic volume, and the average vehicle speed calculated based on the road resistance function using the real-time traffic volume data. After the tunnel fire occurred at time t0, vehicles in the non-accident tunnel and downstream of the accident point in the accident tunnel exited the tunnel normally and quickly, completing the evacuation. However, vehicles in the section from upstream of the accident point in the accident tunnel to the entrance were in a stopped and waiting phase, and vehicles inside the tunnel were in state B. Vehicles upstream of the accident point began to lag and queued up. At this time, the vehicle speed and flow at the accident point section were both 0. The traffic density in state B was based on the total number of delayed vehicles N. V The distance L from the accident site to the upstream tunnel entrance d Calculations show that a converging wave ω is formed at the accident section. AB The fire spread downstream of the accident site, with traffic congestion reaching its maximum impact after time period T1. Delayed vehicles upstream of the accident site consist of two parts: a 2km radius upstream is designated as a parking and evacuation zone, where vehicles and occupants must immediately disembark and evacuate after the fire breaks out; vehicles outside this 2km radius remain in place until all rescue vehicles arrive at the scene, at which point they will be evacuated via the cross passage. Vehicles outside the parking and evacuation zone can leave the accident tunnel via the nearest cross passage after all rescue vehicles arrive, and then exit through the non-accident tunnel to complete the evacuation. Vehicles within the parking and evacuation zone must wait until the fire is effectively controlled, after which rescue personnel will guide occupants back to their original vehicles from a safe area before evacuation. The evacuation pattern is the same as for the non-parking and evacuation zone: accident tunnel - cross passage - non-accident tunnel evacuation mode.

[0052] After time t1, vehicles upstream of the accident site begin to be diverted towards the non-accident tunnel via the nearest vehicular cross passage, forming an evacuation wave ω at the cross passage section of the accident tunnel. BC The downstream traffic flow, from the upstream congestion queue at the accident site to the vehicular cross passage and then to the non-accident tunnel, is in state C. This can be understood as the continuous traffic flow passing through the bottleneck section, as follows: Figure 4 As shown. After the traffic diversion process begins, the traffic flow that is congested and queuing in the three lanes must first change lanes to merge into a single lane in order to pass through the cross passage. At this time, the tunnel capacity is reduced to a single-lane scenario. Therefore, the traffic flow in this state is the single-lane capacity, so the deceleration rate of the merging wave is relatively slow. Therefore, t1 refers to the starting time of the cross passage diversion phase, which is the moment when the first vehicle enters the cross passage.

[0053] At time t2, after the first vehicle enters the non-accident tunnel from the vehicular cross passage, a new evacuation wave ω is formed. CDThe traffic flow propagates downstream from the exit of the cross passage. After the vehicles delayed upstream of the accident point travel through the cross passage to the non-accident tunnel, the non-accident tunnel is now clear, and its capacity is restored to the designed capacity. At this time, the vehicles in the tunnel are in state D, and their speed is restored to the speed limit. Therefore, t2 refers to the start time of the non-accident tunnel clearance phase, which is the time when the first vehicle exits the cross passage and arrives at the non-accident tunnel. t2-t1 is the time from when the first vehicle enters the cross passage to when it exits the cross passage.

[0054] Calculate the total number N of delayed vehicles based on traffic parameters in a tunnel fire scenario. V :

[0055] Traffic parameters in a tunnel fire scenario are shown in Table 1.

[0056] Table 1

[0057]

[0058] The total number of vehicles delayed upstream of the tunnel fire accident site consists of two parts: one part consists of vehicles that entered the tunnel after the fire but before the tunnel was closed, and the other part consists of vehicles that had already entered the tunnel before the fire. The total number of delayed vehicles can be calculated by the following formula:

[0059] N V =Q s ·t b +K A ·L d Equation (1)

[0060] Kn—Traffic density in the tunnel before the accident (veh / km);

[0061] Taking the traffic flow parameters and accident scenario parameters in Table 1 as examples, the total number of delayed vehicles upstream of the accident point is calculated to be 863. After the tunnel fire, the congestion-relief process of the delayed traffic flow upstream of the accident point includes the following four states:

[0062] Calculate the traffic flow density in state A of the traffic diversion process:

[0063] As shown in equation (2), the average vehicle speed in state A is calculated based on real-time traffic volume data using the road resistance function, and the traffic density can be further calculated. The average vehicle speed, calculated based on real-time traffic volume data using the road resistance function, is 61 km / h, and the traffic density can be further calculated as 86 veh / km.

[0064] Calculate average vehicle speed using the road resistance function:

[0065]

[0066] In the formula, V0 is the free driving speed of social vehicles (km / h), which can be taken as the speed limit of 80km / h;

[0067] Q i — Actual traffic volume (veh / h) on the corresponding road segment;

[0068] C i —Design traffic volume (veh / h) for the corresponding road section.

[0069] α, β — parameters to be determined, which can be calibrated based on historical traffic data analysis of specific road sections, or

[0070] The values ​​should be selected based on the empirical values ​​in Table 2.

[0071] Table 2 Suggested values ​​for undetermined parameters of the path resistance function.

[0072]

[0073] The traffic density in the tunnel before the accident was calculated according to formula (3);

[0074] Qs = K A ·V A Equation (3)

[0075] In the formula, Qs is the traffic volume (veh / h) in state A of the traffic diversion process.

[0076] K A —Traffic density (veh / km) in state A of the traffic diversion process;

[0077] V A —The average speed (km / h) of vehicles in state A during the evacuation process is calculated according to formula (2).

[0078] Calculate the traffic flow density in state B of the traffic diversion process:

[0079] Following the tunnel fire, traffic congestion and queuing occurred upstream of the accident site. At this point, both the vehicle speed and flow rate at the accident site were zero. Based on the total number of delayed vehicles N... V The traffic density in scenario B can be calculated using the following formula. When the tunnel fire occurs 8km from the tunnel entrance, the traffic density in this scenario is approximately 108veh / km.

[0080]

[0081] In the formula, K B —Traffic density (veh / km);

[0082] N V —Number of vehicles delayed within the road section (veh);

[0083] L d —Distance from the accident site to the upstream tunnel entrance (km).

[0084] Calculate the traffic density in state C of the traffic diversion process:

[0085] After the vehicle evacuation upstream of the accident site begins, vehicles distributed on the three lanes of the main tunnel need to be diverted to the non-accident tunnel via the vehicle cross passage. During this process, the queuing vehicles in the three lanes first need to change lanes and merge into one lane before they can enter the vehicle cross passage. At this time, the tunnel's traffic capacity is reduced to a single-lane scenario, so the traffic flow in this state is the single-lane traffic capacity.

[0086] Taking a typical tunnel project as an example, the width of the cross passage is 6.5m, which is greater than the width of a single lane inside the tunnel. Therefore, the conservative value for the cross passage's traffic capacity is 2100veh / h. Since deceleration and turning are required when entering the cross passage, the average speed for passing through the cross passage is taken as 20km / h according to the design requirements. From this, the traffic density can be calculated to be approximately 105veh / km.

[0087] Obtain the traffic flow density in state D of the traffic diversion process:

[0088] After the delayed vehicles upstream of the accident site travel through the cross passage to the non-accident tunnel, the tunnel is now clear, and its capacity is restored to the designed capacity. The capacity is restored to the designed capacity of 6300 veh / h, and the speed limit is restored to 80 km / h. Therefore, the calculated traffic density is 78.75 veh / km.

[0089] Table 2

[0090]

[0091] S2: Calculate the traffic flow wave for each traffic diversion process based on the traffic flow density of each process:

[0092] The wave velocity of traffic flow is calculated using the following formula: a positive wave velocity indicates that the traffic flow wave is propagating upstream, while a negative wave velocity indicates that it is propagating downstream. The traffic flow wave formed when the traffic flow changes from high density to low density is a dispersing wave, and vice versa, it is a gathering wave.

[0093]

[0094] ω AB To alleviate the traffic flow wave in states A through B of the process;

[0095] ω BC To alleviate the traffic flow wave in states B to C of the process;

[0096] ω CD For the traffic flow wave in states C to D during the clearing process;

[0097] Equation (5) is derived based on the traffic flow wave theory. The derivation process is as follows: Figure 5 and Figure 6 As shown, assume the time interval between traffic flows passing through sections I and II is Δt, the distance between the two sections is Δx, the inflow of traffic at section I is Q, the density is K, and the outflow at section II is (Q + ΔQ). Because the flow rate increases between sections I and II, the density between sections I and II decreases, and the density at section II is (K - ΔK). The traffic flow process is as follows. Figure 5 As shown. According to the law of conservation of mass, the traffic flow continuity equation can be expressed by the following formula:

[0098] [Q―(Q+ΔQ)]Δt=[K―(K―ΔK)]Δx

[0099] When Δt→0 and Δx→0, we can obtain:

[0100]

[0101] The conservation equation is essentially used to represent the density wave (traveling wave) equation. Traveling waves have the property that the wave amplitude remains constant along the characteristic line, meaning that the traffic flow density does not change with time along the characteristic line. The characteristic lines of the traveling wave solutions for traffic flow under a single density state are parallel to each other. However, when two different traffic flow density states meet, the corresponding characteristic lines of the different density states intersect, thus generating a traffic flow wave.

[0102] Taking the evacuation of delayed vehicles upstream of the tunnel accident site via a cross passage as an example, such as Figure 6 As shown, assume the average speed of traffic flow in the main tunnel is V1, the density is K1, the average speed of traffic flow in the cross passage is V2, the density is K2, and the speed at point S in the cross passage is V. w During the time interval Δt of the traffic diversion process, the number of vehicles passing through section S is:

[0103] N s =(V1―V w K1(x,t)Δt=(V2―V w K2(x,t)Δt

[0104] Based on the relationship between flow rate, density, and velocity, the change can be obtained as V. w The formula for calculating the wave velocity of a traffic flow is as follows: V w The criteria for determining the path of traffic flow waves are as follows: a positive wave velocity indicates that the traffic flow wave is propagating upstream, while a negative wave velocity indicates that it is propagating downstream.

[0105]

[0106] S3: Calculate the maximum impact range of traffic delay based on the traffic flow waves of each diversion process, i.e., the maximum congestion length L. w It can be calculated using the following formula.

[0107]

[0108] After the traffic control phase begins following a tunnel fire, vehicles upstream of the fire site receive fire information via variable message signs or emergency broadcasts and stop on the spot as required. Simultaneously, the tunnel entrance is closed, preventing vehicles from entering. During this phase, traffic flow is dominated by mandatory traffic management measures and no longer controlled by the rally wave, meaning the rally wave is interrupted. Therefore, the rally wave transmission time T1 during the queuing process due to traffic delays is the time interval between the fire and tunnel closure. In this embodiment, considering T1 = 120s, the maximum queue length is calculated to be 7.96km.

[0109] Based on the propagation time of the queuing process, the wave velocity of the traffic flow at different stages can be calculated using the following formulas: T2 = 41s, T3 = 179s. After the traffic flow begins to clear through the cross passage, the travel time of the first vehicle cleared from the accident tunnel to the non-accident tunnel is t2-t1, which can be calculated using the following formula:

[0110]

[0111] In the formula, L H This indicates the length of the cross passageway for vehicles, which is set to 50m in this embodiment; V H This represents the average speed of vehicles passing through the cross passage. Considering the deceleration process when entering the cross passage, a value of 20 km / h can be used.

[0112] Based on the above calculation process, such as Figure 7 The time required for traffic to be diverted from the upstream of the tunnel fire incident to the non-accident tunnel is:

[0113]

[0114] Since people in the parking evacuation zone (within 2km upstream of the fire site) have already disembarked and evacuated after the fire broke out, vehicles in this area must wait until the fire is effectively controlled and people return to their original vehicles before evacuation can begin. The return time is calculated based on the principle of proximity, considering the maximum walking distance is twice the distance between pedestrian crosswalks (the distance between pedestrian crosswalks in non-accident tunnels + the distance between pedestrian crosswalks in accident tunnels), approximately 500m. Assuming a return speed of 1.13m / s, the return time from the safe area to the original vehicle is approximately 442s. Assuming the delayed vehicles are evenly distributed upstream of the fire site, the evacuation time for vehicles in the parking evacuation zone after people return to their original vehicles is calculated using the same method. The overall evacuation time for vehicles in the parking evacuation zone can be expressed by the following formula:

[0115] TS(e) =t e +T s

[0116] In the formula, t e —Time (s) for personnel to return to their original vehicle;

[0117] T s —Time (s) of delaying traffic flow.

[0118] A system for assessing traffic flow evacuation time in tunnel fire emergency rescue effectiveness resilience evaluation includes a memory, a processor, and a computer program stored in the memory. When the processor executes the program, it implements the method for assessing traffic flow evacuation time in tunnel fire emergency rescue effectiveness resilience evaluation.

Claims

1. A method for predicting the evacuation time of a vehicle flow for tunnel fire emergency rescue efficiency and resilience assessment, characterized in that, The method comprises the following steps: S1. Establish the delay traffic flow dissipation process, calculate the vehicle flow density K of each dissipation process A , K B , K C , K D , obtain the vehicle flow Q of each dissipation process A , Q B , Q C , Q D ; Before the tunnel fire, the vehicles in the tunnel are in state A, the traffic volume in the tunnel is the real-time traffic volume, and the average speed is calculated based on the real-time traffic volume data according to a road resistance function; After the tunnel fire occurs at t0, the vehicles downstream of the accident point in the non-accident tunnel and the accident tunnel are quickly driven out of the tunnel to complete the evacuation, the vehicles in the interval from the accident point to the entrance in the accident tunnel are in a parking waiting stage, the vehicles in the tunnel are in state B, and the speed and flow of the vehicles at the section of the accident point are both 0; After t1, the vehicles upstream of the accident point start to evacuate to the non-accident tunnel through the nearest crosswalk, and the traffic flow from the congestion queue upstream of the accident point to the crosswalk to the non-accident tunnel evacuation process is state C; After the first vehicle drives into the non-accident tunnel from the crosswalk at t2, the traffic capacity is restored to the design traffic capacity, the vehicles in the tunnel are in state D, and the speed of the vehicles is restored to the speed limit; S2. According to the vehicle flow density of each evacuation process, the vehicle flow wave of each evacuation process is calculated: ω AB is the traffic wave in the state of the process of dissipation A-B; ω BC is the traffic wave in the state of the process of dissipation B-C; ω CD is the traffic wave in the state of the process of dissipation C-D; S3. Calculate the time T for the upstream traffic to disperse to the non-accident tunnel at the tunnel fire accident point s ; T1 is the time interval between the occurrence of a fire and the closure of the tunnel; L H represents the length of the cross passage, V H represents the average speed of the vehicles passing through the cross passage; S4. Calculate the tunnel fire vehicle evacuation time T S(e) : T S(e) = t e + T s In the formula, t e Personnel return to the original car time.

2. The prediction method of claim 1, wherein, The step S1 further comprises: According to the traffic parameters under the tunnel fire scenario, the total number of delayed vehicles N is calculated V and the traffic density K of the loosening process state A n , the interval average speed V of the loosening process state A A ; N V = Q s · t b + K A · L d ; Q s Q is the real-time traffic volume of A state, t b L is the time after the accident and before the tunnel is closed d D is the distance from the accident point to the upstream portal V0 is the free speed of social vehicles, which is taken as 80 km / h; Q i is the actual traffic volume of the corresponding section, C i is the designed traffic volume of the corresponding section, and α, β are undetermined parameters, i is the tunnel section. The vehicle flow density of the evacuation process state B is calculated as follows: K B is the traffic density (veh / km) for the disaggregated process state B; L-L d is the distance of the accident point from the upstream portal; The vehicle flow density of the evacuation process state C is 105 veh / km. The vehicle flow density of the evacuation process state D is the ratio of the design traffic capacity to the speed limit.

3. The prediction method of claim 1, wherein, t b = 2 min.

4. The prediction method of claim 1, wherein, When the number of lanes is greater than 2 and the road section is a highway, α=0.390 and β=1.331; when the number of lanes is greater than 2 and the road section is a general road, α=0.777 and β=1.

897.

5. The prediction method of claim 1, wherein, When the number of lanes is equal to 2 and the road section is a highway, α=0.515 and β=1.569; when the number of lanes d is equal to 2 and the road section is a general road, α=1.287 and β=1.

891.

6. A system for predicting the evacuation time of a vehicle flow for tunnel fire emergency rescue efficiency and resilience assessment, comprising a memory, a processor and a computer program stored on the memory, characterized in that, The processor implements the prediction method of any one of claims 1-5 when executing the program.

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