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Summary Many studies have been conducted on the evacuation behavior on the staircases of buildings, but very little data are available for a situation with many occupants in a crowded high-rise building. Therefore, this study investigated the evacuation behavior of a large number of evacuees on the staircase of a 25-story high-rise building. A total evacuation drill was conducted with 2088 evacuees, and the behavior of 1136 evacuees on the landings of the south staircase was recorded by a video recorder on the ceiling. The relationship between the density and speed of the evacuees on the landings was analyzed from the evacuation data for two situations: without and with merging in the stair flow. The evacuation stair flow in this drill had merging occupants entering from the floors, but no one entered from the lower floors during the latter period of the drill. Therefore, the flow during the latter period was treated as non-merging flow, for which it was observed that, when the staircase was fully crowded, the density on the landings in the moving situation was different from that in the stopped situation. Moreover, the density on the landings was different from that on the treads. Furthermore, in the merging flow, a merging ratio of approximately 50:50 occurred during the congested evacuation. Copyright © 2016 John Wiley & Sons, Ltd.

Tsunami evacuation plans have been deliberately developed by local governments in coastal areas in Japan under guidance from the national government since before the Great East Japan Earthquake in March 2011. These plans, however, do not mention the time required for all local residents to evacuate to evacuation areas. This paper reports a procedure to design an effective tsunami safe town planning using multi-agent simulator (MAS) which identify a degree of evacuation risk in objective area. A case study is applied to one of the worst hit town of tsunami, in which additional facilities such as evacuation areas, safe buildings, and evacuation routes are proposed as well.

Ticket gates in railway stations or stadiums and security gates in office buildings pose difficulties for evacuation in in case of fire. This paper focuses on the characteristics of a crowd passing through the ticket gates of Japanese railway stations. The characteristics of a crowd flow passing through ticket gates were identified, and numerical values were derived to estimate the evacuation time. A total of 48 subjects were asked to pass through a ticket gate with three passages and three different wide passages, where each width was the same as the sum of the three passage widths of the ticket gate. The crowd flow through the ticket gate was simulated with the pedestrian simulation model SimTread. The results of this study elucidated the flow rate through the ticket gates and the numerical values to calculate the time for evacuation planning.

The present paper is designed to provide a summary of our study on the high temperature corrosion of Al2O3, SiO2 and Al2O3–SiO2 forming alloys in the gas phase and liquid phase of Na2SO4–NaCl system by comparing their corrosion resistance at 1000 °C. The obtained results show that the alumina-forming alloy experiences severe internal corrosion in the gas phase compared to in the liquid phase due to oxide cracking. This results in an increase in the inward diffusion and/or penetration of constituents of the salts and oxygen to form internal Al-oxide and Cr-sulfides. In the liquid phase, however, the formation of yttrium sulfide beneath a continuous double oxides layer of Al5Y3O12 and Al2O3 may be related to the high affinity of yttrium for sulfur. On the other hand, it is apparent from the cross-sectional observations that a SiO2 and Al2O3–SiO2 forming alloys form a continuous and dense oxides layer, and demonstrate a high resistance against internal oxidation and corrosion in both corrosive environments.

The high temperature corrosion behavior of Si-containing alloys consisting of Cr-Si-Ni and CoNiCrAlY-Si alloys fabricated by spark plasma sintering technique was investigated in the liquid phase of Na2SO4 + 25.7 mass% NaCl at temperatures ranging from 923-1273 K. The purpose of this study is to develop excellent corrosion resistant alloys for coating applications. Our experimental results show the CrSi2 alloy with 10 mass% Ni content and the CoNiCrAlY alloy with 30 mass% Si content are the most promising materials for applications in this atmosphere. This is due to the formation of a protective SiO2 and Al2O3/SiO2 scale, respectively. The formation of a dense and continuous oxide layer composed and/or consisted of SiO2 plays a significant role in hindering the inward diffusion of chlorine and sulfur to the alloys substrate. Particularly, the corrosion mechanism of Cr-Si-Ni alloys and the influence of Ni addition on the corrosion resistance of CrSi2 alloy are discussed in the present paper.

The objective of this study is to develop an excellent corrosion resistant alloy for high temperature coating applications. The Si-containing alloys consisting of CoNiCrAlY and CrSi2 alloys with varying Si and Ni content respectively were prepared by spark plasma sintering (SPS) technique. The corrosion behavior of these alloys was investigated in the gas phase of air-(Na2SO4+25.7mass%NaCl) at elevated temperatures of 923, 1073 and 1273K. The results showed that CoNiCrAlY alloy with 30mass% Si content and CrSi2 alloy with 10mass% Ni content were the most effective materials for application in the gas phase of air-(Na2SO4+25.7mass%NaCl) due to the formation of protective Al2O3/SiO2 and SiO2 scale, respectively. Therefore, it is realized that CoNiCrAlY-30mass% Si and CrSi2-10mass% Si coating are very effective for improving of high temperature corrosion resistance of STBA21 steel.

The addition of Si to CoNiCrAlY was considered in order to develop corrosion resistant alloys for coating applications. The high temperature corrosion behavior of spark plasma sintered CoNiCrAlY alloys of 0, 10, 20, and 30 mass% Si content was investigated in an air-(Na2SO4+25.7 mass%NaCl) gas atmosphere at elevated temperatures of 923, 1073, and 1273 K. The results showed that CoNiCrAlY-Si alloys formed mainly an Al2O3 or Al2O3/SiO2 scale, depending on the alloy composition and the temperature. The addition of 30 mass% Si significantly improved the high-temperature corrosion resistance of CoNiCrAlY alloy in an air-(Na2SO4+25.7 mass%NaCl) gas atmosphere at these temperatures. The high temperature corrosion behavior of CoNiCrAlY-Si alloys was discussed in the present paper.

SimTread has been developed as a pedestrian simulation system with straightforward pedestrian and space model, which is highly operable by the users. The pedestrian model is a multi agent system in which the individual pedestrian is modeled as agents, and the space model is based on real coordinates, on the contrary of network and mesh models, that enable to represent plans directly into models.The characteristics of crowd represented in this system had been evaluated through test cases by measuring the flow rate that is a major index for evaluating crowd.Major results are as follows 1. In a simple plan that are comparable to network models, SimTread showed reasonable behaviours of crowds, which in terms of operability, can be concluded as highly desirable performance. 2. In a case where a bottleneck accumulates enough pedestrians so that consecutive exits will be virtually closed, SimTread showed accurately the propagation of crowd, which led to qualitative analysis of the crowd.

The purpose of this study was to investigate the effects of merges on crowds in a staircase and the ease of merging with variations in crowd density, directions of merge, and whether the door joining a hallway to a staircase was opened or closed. The results led to the following conclusions: 1) merging is easier at lower population density; 2) merging is easier if the direction of the merging crowd is same as the direction of the crowd in the staircase; and 3) merging is easier if the door is initially opened, and the evacuation speed is decreased by 30% when the door is initially closed.

The purpose of the study is to investigate the criterion for the force required to open fire doors, and the required dimensions of fire door frames, from an ergonomic point of view for wheelchair users, through conducting experimental studies on passing through fire doors.This study implemented two types of experimental design, observing subjects passing through fire doors, and measuring the force required to open them.The results of the study show that it is desirable for fire doors to have a required opening force of no more than 40N and a width of more than 850mm. When using a wheelchair, the direction from which the door is approached has a significant impact on whether or not the subject can pass through the door. From these observations, it is postulated that in cases where corridors are narrow and there is not sufficient room to maneuver a wheelchair, a wheelchair user will often be unable to evacuate safely to the stairwell if they approach the fire door from the door knob side. Therefore it is essential that there is sufficient space in front of the fire door to bring a wheelchair parallel to the door, and also to rotate the wheelchair 180 degrees when necessary.