Evacuation Situations Research Articles

Incorporating Household Gathering and Mode Decisions in Large‐Scale No‐Notice Evacuation Modeling

AbstractHousehold members tend to evacuate as a unit. However, most engineering‐based evacuation models treat evacuees as independent and separate entities, and overlook the interactions among household members during an evacuation (i.e., gathering children/spouses or uniting with other family members at home). The omission of these behaviors leads to imprecise modeling of evacuation situations. Additionally, transportation mode choice in a no‐notice evacuation has been seldom investigated. We present a framework to incorporate both household‐gathering behavior and mode choice in an emergency into an evacuation model to examine the effects of these two issues on evacuation efficiency and network performance. The framework was tested in the Chicago metropolitan region for two hypothetical incidents with evacuation radii 5 and 25 miles. Models that omit gathering behavior yield dangerously optimistic evacuation times and network congestion levels compared to models that include family interactions. These optimistic estimates are significant for a large‐scale evacuation—the reduction in the number of evacuees who can reach safe zones in a certain time threshold is nearly 50% between the gathering and no‐gathering models. Gathering behavior could also cause distinct effects on network performance for inner and outer areas, the break point of which may be where severe bottlenecks are located. In this study, average travel speed increases on the overall network within 15 miles of the incident location (where downtown Chicago is located), but decreases outside the 15‐mile radius. These results would be completely overlooked without incorporating the gathering behavior yet are critical for evacuation management.

Application of Mathematical Model of Evacuation for Large Stadium Building

The statistics of sports arena accidents show that the main reasons which leading to crowd stampede are the exports blockage and the poor surrounding transportations. In the process of evacuation, the most common problem is that there are a large number of people are stranded and also they are the main carrier which leading to crowded stampede. With large amounts of data and reasonable evaluations on staffs and transportation instruments. We propose inflow model in the crowding state, principle of maximum flow on channel design, optimal model of vehicle parking, evacuation model of subways and buses, according to sections of evacuation in stadiums. We analyze their usage area, marginal conditions and real data. Finally, we get some valuable results, which are curves of density and flow, evacuation time, formula for channel design, optimal parking design and formulas for evacuation time of subways and buses. Such data suits the real data from varied references. With the help of models and results, we get the total time of evacuation, simulation of progress and give parts of real situations of evacuation. According to such results, 100000 people's evacuation can be finished in about 45 min. On such basis, we propose some optimal plans for stadium and its surroundings building.

Proposing Effective Method to Develop Common Operational Picture in Disaster Response Utilizing Cloud-based Geospatial Infrastructure

The concept of Mashup, which refers to forming a new service by combining technologies and contents from multiple sources, already exists after Web2.0 in the field of software development; however, its concept was not converted well to social service yet. After Tohoku Earthquake ministries and agencies in Japan found it necessary to organize the pieces of information in a geospatial manner in order to take a comprehensive, panoramic view of situations at the site. We organized the Emergency Mapping Team (EMT) as to be able to gather and analyze the information in the cooperative relationship with government. For example under the serious situation of Fukushima Nuclear accident the EMT organized the layers of the impacted area including the information about indicating the locations of buildings, the evacuation situations in areas under directives to evacuate. Using those layers disaster responders simulated the necessity of human and material resources to support the evacuation operation. In this activity, we have stored the outcomes as spatial layers into the Cloud-based Spatial Data Infrastructure. After this activity at the Cabinet Office, we moved our focus to Iwate Prefecture affected by huge tsunami. Utilizing this infrastructure, the responders at Iwate just added the detail of data which only they gathered through their disaster response, and they could develop the COP in their own view points. In this paper, we discuss the effective method to develop COP utilizing the Cloud-based Spatial Data Infrastructure from the view point of all-Japan to the one of limited affected area.

Differences in Driving Characteristics between Normal and Emergency Situations and Model of Car-Following Behavior

This paper presents results of an exploratory study on differences in driving characteristics between normal and emergency situations and builds up the car-following model under the emergency evacuation situation. The simulation scenario has been given to create a driving environment under the emergency evacuation situations. Questionnaire investigations and the electrocardiogram/heart rate monitor are used to verify the validity of the driving environment from both subjective and objective perspectives. Perception reaction time (PRT) and the critical headway are taken as two indicators to describe driving characteristics. The results show that PRT is in accord with normal distribution under both normal and emergency situations. The value of PRT under the emergency situation is lower than that under the normal situation. The results also show that critical headway under the emergency situation is smaller than that under the normal situation. A back propagation (BP) neural network is designed in this study. A combination of the Levenberg-Marquardt BP algorithm and Bayesian regularization is employed to train the network. Gray-correlation analysis is conducted to determine which factors have a great impact on the acceleration of the following car. Simulation of the BP neural network using data collected from driving simulator reveals that the BP neural network has a high precision in the prediction of the car-following model.

A Simulation‐Based Dynamic Stochastic Route Choice Model for Evacuation

This paper establishes a dynamic stochastic route choice model for evacuation to simulate the propagation process of traffic flow and estimate the stochastic route choice under evacuation situations. The model contains a lane‐group‐based cell transmission model (CTM) which sets different traffic capacities for links with different turning movements to flow out in an evacuation situation, an actual impedance model which is to obtain the impedance of each route in time units at each time interval and a stochastic route choice model according to the probit‐based stochastic user equilibrium. In this model, vehicles loading at each origin at each time interval are assumed to choose an evacuation route under determinate road network, signal design, and OD demand. As a case study, the proposed model is validated on the network nearby Nanjing Olympic Center after the opening ceremony of the 10th National Games of the People′s Republic of China. The traffic volumes and clearing time at five exit points of the evacuation zone are calculated by the model to compare with survey data. The results show that this model can appropriately simulate the dynamic route choice and evolution process of the traffic flow on the network in an evacuation situation.

Smooth/non-smooth contact modeling of human crowds movement: numerical aspects and application to emergency evacuations

The aim of this paper is to develop on discrete models that reproduce the behavior of a crowd of people in several emergency evacuation situations. The first step in this study is to determine how to treat contacts between pedestrians. For that, three already existing discrete approaches, one smooth and two non-smooth, originally proposed to simulate the collisions of granular assemblies, are first analyzed both from the theoretical and the numerical point of view. The solving algorithms are presented and the numerical formulation of the two non-smooth approaches is compared to standard plasticity in order to point out the common theoretical framework. The next step is to adapt these discrete approaches to represent pedestrians. The key point is to introduce a “willingness” for each particle through a specific desired velocity. These adapted discrete approaches are able to handle local interactions, like pedestrian-pedestrian or pedestrian-obstacle contacts, in order to reproduce the global dynamic of pedestrian traffic. Finally, results of several simulations in emergency configurations are presented as well as compared to real exercise ones.

Modeling Fire Evacuation of a Library Building based on the Numerical Simulation

Problem statement: This study investigates the fire evacuation problem of the library building by using the Fire Dynamics Simulator with Evacuation (FDS+Evac.) programming. Approach: The assumption is made that the sprinkler system is installed in the building but the system is malfunction, which is considered as the worst case of the situation. The simulations are divided into 4 cases, which are case 1; the numbers of evacuating persons are 517 persons and the heat release rate is 5 MW, case 2; the numbers of evacuating persons are 517 persons and the heat release rate is 7 MW, case 3; the numbers of evacuating persons are 788 persons and the heat release rate is 5 MW and case 4; the numbers of evacuating persons are 788 persons and the heat release rate is 7 MW. Results: The results are shown that the 1st case and the 2nd case have the evacuation times of 8.63 and 8.81 min, respectively. There is no dead person found from both cases. For the 3rd and the last case, the evacuation times are 18.17 and 18.83 min, respectively. The 3rd case has 1 dead person and the last case has 18 dead persons, respectively. Conclusion: The number of evacuating person and a size of fire have a directly impact on the evacuating person. The reasons are the crowded situation of evacuation and a higher toxicity that is occurred. So, the stairway of the building has to be improved and changed to be the fire escape. This brings to the increasing in the capability of the evacuation.

Potential of Social Modelling in Socio-Technical Systems

While modelling (and simulating) a socio-technical system, the primary focus has been on the technological side almost ignoring the social dimension of it. However, with recent advancements in Ambient Intelligence (AmI) and emotions sensing technologies, it is now possible to fill this gap. To this end, we have integrated cognitive decision making model abstracted from psychological, neurological and social theories of human behaviour in evacuation situations into a simulated environment, assisted by AmI technology. Initial simulation findings are reported in this paper, keeping focus on a scenario in which a small population of agents is technologically assisted. The results are: (i) the technologically assisted agents emerge as leaders during evacuation changing the intentions of most of the agents, and (ii) even a small population of such leaders is sufficient to guarantee an efficient evacuation due to leader following behaviour emerging as a social phenomenon.

Simulation Model for Urgent Evacuation at Aircraft Accident

In this paper, the urgent evacuation behavior of passengers at aircraft accident is formulated as a simulation model which consists of two models such as a two-dimensional grid cell model and an autonomous and multiple agents' system model. The former model represents the layout of cabin interior and the allocation of passengers. On the other hand, the latter shows the behavior of evacuation of passengers from inside of a cabin to outside of an aircraft using emergency equipments such as an emergency exit and escaping slide. This autonomous agent is able to obtain the necessary information for urgent evacuation within one's field of view and decide to select the escaping route by means of obtained information concerned with escaping path to the nearest emergency exit. By the comparable study between the results of the proposed simulation and the accident analysis reports on “Garuda Indonesia Airways Accident on 1996” and “China Airline Accident on 2007 ,” it is verified that the proposed simulation system enable one to estimate the situation of urgent evacuation in the aircraft accident.

A MACROSCOPIC CROWD MOTION MODEL OF GRADIENT FLOW TYPE

A simple model to handle the flow of people in emergency evacuation situations is considered: at every point x, the velocity U (x) that individuals at x would like to realize is given. Yet, the incompressibility constraint prevents this velocity field to be realized and the actual velocity is the projection of the desired one onto the set of admissible velocities. Instead of looking at a microscopic setting (where individuals are represented by rigid discs), here the macroscopic approach is investigated, where the unknown is a density ρ(t,x). If a gradient structure is given, say U = -∇D where D is, for instance, the distance to the exit door, the problem is presented as a Gradient Flow in the Wasserstein space of probability measures. The functional which gives the Gradient Flow is neither finitely valued (since it takes into account the constraints on the density), nor geodesically convex, which requires for an ad hoc study of the convergence of a discrete scheme.

Evacuation in practice — Observations from five full scale exercises

Evacuating a ship is a difficult task which normally is performed under severe and demanding conditions, exposing both crew members and passengers on board to an extreme and demanding situation. To be prepared for an incident happening on board and shouldering this responsibility is part of the everyday reality of the crew members’ work situation. This study reports the results from observations made on board five passenger ships performing full scale exercises with participants acting as passengers. The results pointed out four problem areas; the safety organization, the ability to perform tasks, the handling of life vests and communication. These areas represented an uncertainty in the requirements associated with the crew members’ role in the safety organization implied. There was also evidence of difficulties in the crews’ performing of different tasks, problems with donning life vests and insufficient communication. The crew member groups on board differ in their skills and knowledge to handle an evacuation situation. These groups need to be studied separately and systematically in order to determine how they comprehend their work situation and what their needs of preparation and training are in order to feel content with meeting the demands of their role in the safety organization.

Multiobjective Optimization for Multimodal Evacuation

This paper proposes a multimodal optimization framework that combines vehicular traffic and mass transit for emergency evacuation. The multi-objective approach optimizes the multimodal evacuation framework by investigating three objectives: minimizing in-vehicle travel time, minimizing at-origin waiting time, and minimizing fleet cost in the case of mass transit evacuation. For auto evacuees, an optimal spatiotemporal evacuation (OSTE) formulation is presented for generating optimal demand scheduling, destination choice, and route choice simultaneously. OSTE implements dynamic traffic assignment techniques coupled with genetic optimization to achieve the objective functions. For transit vehicles, a multiple-depot, time-constrained, pickup and delivery vehicle routing problem (MDTCPD-VRP) is formulated to model the use of public transit shuttle buses during evacuation. MDTCPD-VRP implements constraint programming and local search techniques to achieve the objective function and satisfy constraints. The OSTE and MDTCPD-VRP platforms are integrated in one framework to replicate the impact of congestion caused by traffic on transit vehicle travel times. This paper presents a prototype implementation of the conceptual framework for a hypothetical medium-size network in downtown Toronto, Ontario, Canada. The results show that including the waiting time and the in-vehicle travel time in the objective function reduced the network clearance time for auto-evacuees by 40% compared with including only the in-vehicle travel time. For mass transit, when considering fleet cost, an increase of 13% in network clearance time for transit evacuees was observed with a decrease of 12% in fleet size. Mass transit was shown to provide latent transportation capacity that is needed in evacuation situations.

A review of planning and operational models used for emergency evacuation situations in Australia

Thos paper focuses on planning and modelling bush fire-related evacuation, which is perhaps the most difficult disaster situation faced in Australia. It includes a discussion of the available data and the current Australian methods for analysis and planning. The paper concludes with a specification of the needs for models related to advance planning for potential emergencies (largely for bush fires) and for operational models for tactical application in dealing with emergencies, either in simulation exercises or in real circumstances. This includes the identification of critical locations in road networks. There has been some research on the development of a dynamic stated choice procedure for evacuation decision making under bush fire events, but much more research is required. The stated choice procedure could include visualisation to enhance the presentation of alternate scenarios.

FROM CROWD DYNAMICS TO CROWD SAFETY: A VIDEO-BASED ANALYSIS

The study of crowd dynamics is interesting because of the various self-organization phenomena resulting from the interactions of many pedestrians, which may improve or obstruct their flow. Besides formation of lanes of uniform walking direction and oscillations at bottlenecks at moderate densities, it was recently discovered that stop-and-go waves [D. Helbing et al., Phys. Rev. Lett.97 (2006) 168001] and a phenomenon called "crowd turbulence" can occur at high pedestrian densities [D. Helbing et al., Phys. Rev. E75 (2007) 046109]. Although the behavior of pedestrian crowds under extreme conditions is decisive for the safety of crowds during the access to or egress from mass events as well as for situations of emergency evacuation, there is still a lack of empirical studies of extreme crowding. Therefore, this paper discusses how one may study high-density conditions based on suitable video data. This is illustrated at the example of pilgrim flows entering the previous Jamarat Bridge in Mina, 5 kilometers from the Holy Mosque in Makkah, Saudi-Arabia. Our results reveal previously unexpected pattern formation phenomena and show that the average individual speed does not go to zero even at local densities of 10 persons per square meter. Since the maximum density and flow are different from measurements in other countries, this has implications for the capacity assessment and dimensioning of facilities for mass events. When conditions become congested, the flow drops significantly, which can cause stop-and-go waves and a further increase of the density until critical crowd conditions are reached. Then, "crowd turbulence" sets in, which may trigger crowd disasters. For this reason, it is important to operate pedestrian facilities sufficiently below their maximum capacity and to take measures to improve crowd safety, some of which are discussed in the end.

Review of A Real Multi-story Store Fire by Applying Evacuation and Smoke Movement Interactive Simulation Model

The evacuation and smoke movement interactive simulation model has been developed to handle the evacuation of large populations of individuals with mixed walking capabilities. The advantages of the model are: 1) to handle evacuation of individual evacuees considering variety of behavioral parameters, 2) to handle total evacuation in a multi-story building via the stairs, and 3) to consider interactions between egress behavior and spread of smoke in a building. The system is a deterministic simulation program implemented by the agent-based computer language, Repast. Using this simulation model, we conducted case studies to reproduce the smoke condition and evacuation situation of a real fatal fire of the 1990 Nagasakiya-Amagasaki Store Fire as accurately as possible reflecting the facts from the survey. The calculated results of case studies well agreed with the investigated pattern of risk in evacuation behavior linked with the smoke impacts by the model. We also demonstrated that our simulation model is useful enough to examine possible changes of consequences according to different egress scenarios in order to find possible future issues and solutions for the problems regarding the total evacuation in a multi-story building.

AN APPLICATION OF THE EVACUATION SIMULATION SYSTEM IN CASE OF IMPASSABLE ESCAPE ROUTE

This study aims to apply our simulation system to the evacuation in case of impassable escape route. We model rerouting behavior of evacuee on the evacuation simulation system when the escape route is in trouble. The results are as follows. The evacuation simulation system enables to visualize and analysis the evacuation situation in case of impassable escape route. It takes 7 percent longer time to evacuate on the one-way escape than the two-way escape. It takes 47 percent longer time to evacuate in case of the trouble on the one escape route than the two-way escape. Therefore it is clarified that the evacuation time depends on rerouting behavior to a great extent.

Application of RFID and Video Imaging on Evacuation Observations in Offices and Public Buildings

In this work, two different types of evacuation situations were studied in order to provide validation data for some aspects of the evacuation modeling. The first type was evacuation drills which are normally carried out as part of the safety training of the staff in public buildings and offices. The second type was actual evacuations which occur every now and then. The main techniques used for the observation of evacuation events were video cameras, Radio Frequency Identification (RFID), and surveillance cameras. A large amount of information was obtained and the problems in the application of the observation techniques were identified. In particular, the results show that when the RFID technique is used, the placement of the antennas and tags is very important. With careful placement of the antennas and tags, the reliability of the RFID technique as applied in the current work may be sufficient for scientific purposes. In the observation of an actual evacuation of a large shopping centre, the recordings of the surveillance cameras were used to measure the flow rates of people. The results are very promising and indicate that the collection of surveillance camera recordings from large evacuations should be started.

Performance of expellers in evacuating gas pipelines—Part II: Effects of plug valve and natural gas as a drive gas

Measurements were conducted on a typical commercial 150 mm expeller mounted on stacks with and without a plug valve and driven with natural gas. Expeller performance in terms of its mass induction ratio, correlated to the system equivalent flow resistance coefficient, was found to be the same whether the expeller is driven with air or natural gas. However, in the case of expellers driven with natural gas, the drive gas flow is reduced by a ratio corresponding to the square root of its molecular weight or specific gravity ratio and not the 60% value provided by the American Gas Association (AGA) guidelines in this regard. The effects of the presence of the plug valve along the stack on the suction flow were found to be 40% of that without a plug valve only in free-access cases. In a pipeline evacuation situation, however, the effect was found to be negligible. Revision to the current AGA guidelines is therefore needed.

An analysis of exit availability, exit usage and passenger exit selection behaviour exhibited during actual aviation accidents

AbstractThe exits which passengers select in evacuation situations and the exits which are available post-crash is of great interest to aviation safety regulators who make rulings defining exit separation and aircraft evacuation certification, aircraft designers who develop the interior layout of aircraft cabins and position exits within the fuselage, cabin safety specialists who develop procedures for managing aircraft evacuation and cabin crew who must control aircraft evacuations. In this paper we examine issues associated with passenger exit selection behaviour and exit configurations frequently experienced during survivable crashes. This work makes use of the latest version of the Aircraft Accident Statistics and Knowledge database AASK V4.0, which contains information from 105 survivable crashes and over 2,000 survivors.

Hurricane Katrina and the Flooding of New Orleans: Emergent Issues in Sheltering and Temporary Housing

Hurricane Katrina created an unprecedented need for sheltering and temporary housing across a four-state area along the Gulf Coast. This article reviews the disaster literature with respect to sheltering and temporary housing and contrasts how these needs actually developed with respect to both the preimpact and postimpact evacuation situations. The article also investigates the ways that intergovernmental planning failed to anticipate the need for shelter/housing solutions or to implement effective measures to put those plans into operation.