Fire Doors Research Articles

Experimental Study on the Analysis of Leakage in Aged Fire Doors

Aged fire doors may develop leakage cracks owing to damage from long-term use, leading to issues such as declines in the functionality of pressurization systems. This study analyzes the trends of leakage cracks in aged fire doors based on existing research and field surveys and derives the differential pressure and leakage amounts corresponding to each leakage crack via experiments conducted in a full-scale ancillary room. The results indicate that an increase in the number of leakage cracks tends to result in a decrease in the design differential pressure, which thereby prevents the fire door from performing its intended functions. Moreover, the results confirm that an increase in the number of leakage cracks also affects the leakage amounts.

Thermo-Mechanical Analysis of Masonry Brick Walls with Embedded Test Specimen Under Fire Exposure

AbstractThe present study is dealing with the heat transfer and deformation of masonry brick walls and an embedded fire safety steel door as well as their mechanical interaction when they were exposed to fire. A numerical approach based on the finite element method was applied to predict the temperatures and deformation. The heat transfer analysis of the wall considered the heat conduction and the radiative heat transfer within the voids of the brick. It was found that the thermal analysis predicted the temperature in the wall with high accuracy. The thermal analysis of the door was limited to the heat conduction and the water vapour transport within the door was neglected. However, the calculated temperatures were found to be reasonable and were further used for the structural analysis. When the door was placed in a central position in the wall, the predicted deformation of the wall was in close accordance to the measured data. The analysis of the door deformation showed that the pressure level and its time-dependency inside the steel door is a crucial factor for the simulation’s accuracy. When the door was placed in an asymmetric position, the wall deformation was increasing significantly. This phenomenon was also covered by the simulation, when the stiffness of the wall boundary condition was decreased. Although the numerical model was capable to calculate the deformation during the fire exposure, further research on the pressure inside the door and the mechanical conditions of the wall at the boundaries has to be done.

Simulation analysis and optimization of containerized energy storage battery thermal management system

The air-cooling system is of great significance in the battery thermal management system because of its simple structure and low cost. This study analyses the thermal performance and optimizes the thermal management system of a 1540 kWh containerized energy storage battery system using CFD techniques. The study first explores the effects of different air supply angles on the heat transfer characteristics. Second, the evaluation indexes of heat removal efficiency, air exchange efficiency, temperature and velocity uniformity coefficient are used to select the optimal air supply angle by the Topsis method. Then, the return air vent position is optimized based on the optimal air supply angle, and the optimal solution is obtained. Research indicates that increasing the air supply angle enhances air mixing within the container and simultaneously decreases the battery pack surface temperature. With a 90° air supply angle, the maximum temperature reduces to 33.58 °C, a 19.52 % reduction compared to 30°. The temperature difference across each battery surface also drops by 16.02 % to 3.46 °C. Adjusting the position of the return air vent further improves temperature uniformity and air flow distribution within the battery compartment. When the air supply angle is 90° and the return air vent evenly distributed at Z = 0.85 m next to the fire door, an optimal uniform temperature distribution is achieved. This reduces the maximum surface temperature by 16.47 %, from 36.67 °C to 30.63 °C and decreases the average temperature difference to 3.0 °C, 21.4 % lower. Thus, the present method effectively enhances the performance of the containerized energy storage battery thermal management system.

Optimizing Maintenance Strategies for Public Fire Doors in Apartment Buildings: Study on Deterioration Patterns and Replacement Timing

This study aimed to identify factors contributing to the performance degradation of aging fire doors and determine their appropriate replacement time by analyzing the probability of operation of fire doors using building statistics and expert surveys. Aged fire doors with degraded performance should be repaired or replaced quickly; however, there is no clear standard for fire door repair or replacement. Therefore, we analyzed the operation probability of fire doors and conducted expert surveys to determine the proper replacement timing of fire doors and identify the performance degradation factors. The fire door operation probability survey results showed that fire doors operating for those more than 15 years had more than 20% probability of operation failure, and the main causes of operation failure improper installation, insufficient management, or poor performance. The expert survey results indicated that the optimal replacement period for fire doors is 10 to 15 years. The primary factors contributing to performance deterioration were identified as twisting and corrosion (27%), dents (24%), and damage (20%).

Rancang Bangun Purwarupa Simulasi Sistem Keamanan Rumah Berbasis Internet of Things

The use of information technology has spread to all fields, for example in the field of security using the Internet of Things technology. One of the places that need to be given security is the home, so that in this study prototypes of home security systems using the Internet of Things have been made with the aim of providing information to homeowners in the event of infiltration through windows or doors, gas leaks and fires. The tools used are Arduino Mega 2560 as a microcontroller, gas sensor, fire sensor, magnetic switch sensor, RFID, keypad, and selenoid. The home security system is made so that homeowners can control the condition of the home. The results of this study are that the home security systems that are made can run well and can be integrated with home security information systems. Sensors can detect gas leaks, fires, and doors or windows open when the security system is active. Homeowners can only turn off the home security system and unlock the door by using RFID tags that have registered IDs and correct passwords. Home security systems can also turn on alarms and send notifications to homeowners, fire stations and police stations in the event of a fire, gas leak or window or door that is opened when the security system is active.

Experimental study to determine the emissivity of fire door finishing materials according to calorimetry method

Experimental study to determine the emissivity of fire door finishing materials according to calorimetry method

Experimental study of opening location affecting the delay time of backdraft

Backdraft is a special phenomenon in fire research because of its explosive consequence and the occurrence of uncertainty. The delay time of occurrence has been of interest in recent years as this influences the safety and efficiency of firefighting. This paper investigated the location of the opening and whether it affects the delay time of the backdraft. Results show that the location of the opening dramatically dominates the delay time. The hot/cold air mixing path and instantaneous localized fire ignitions determine the delay time. A ‘curtain-like’ effect for the backdraft time delay was observed. The lower opening demonstrates about 50–70 % delay time compared to the upper and middle locations. In the presence of identical fire conditions and door closure control, the extended flammable gas dilution resulting from the upper opening does not significantly impact the onset of backdraft. Hence, the effective volume above the ignition location determines the delay time of the backdraft. Furthermore, the choice of chamber material is a crucial factor influencing the likelihood of backdraft occurrence. Utilizing a material with enhanced cooling capacity reduces the probability of backdraft. This provides insight into the firefighting and intervention tactics when ventilation-restricted compartment fire occurs.

РАЗРАБОТКА ЭКОНОМИЧЕСКИ ОПТИМАЛЬНОГО МЕТОДА ОЦЕНКИ ВЛИЯНИЯ ХАРАКТЕРИСТИК И РАСПОЛОЖЕНИЯ ФУРНИТУРЫ ПРОТИВОПОЖАРНЫХ ДВЕРЕЙ НА ИХ ОГНЕСТОЙКОСТЬ

The article presents one of the important problems of developing new types of building structures, in particular fire-resistant doors, related to the need for large-scale studies to assess the impact on the fire resistance of door panels of hardware elements, the variety of which leads to significant costs when conducting a full-fledged analysis. This is also due to the fact that a large number of varieties of such elements are currently being developed and they, in turn, can have different effects on the materials used in the production of door panels, the fire-hazardous characteristics of which are known. As part of the development of a cost-effective approach to the study, a methodology has been developed that allows the analysis of small-sized samples. When testing the method, an analysis of the effect of the thickness of the fabric material and the area of the hardware element on fire resistance was carried out. It is thus fixed that the fittings are a refrigerant - they take on the heat passing through the door leaf material and divert it to the environment. Nevertheless, it has also been recorded that with small thicknesses of the structure and rapid heating of the material layer, it is possible to overheat it and reduce the efficiency of heat dissipation, which leads to a rapid decrease in fire resistance. In the case of placing fittings inside the fire door material, the heat removed is transferred to the outer unheated part of the door, thereby initiating its rapid warming up.fittings are a refrigerant - they take on heat and dissipate it into the environment, nevertheless, with small thicknesses of the structure and rapid heating of the material layer, it may overheat and reduce the efficiency of heat dissipation, and if the fittings are placed inside the fire door material, the heat is transferred to the outer unheated part of the door, thereby initiating its rapid heating. The developed method is a cost-effective option for studying the effect of fittings on the fire resistance of doors when choosing its component parts.

Carboxymethylated Lignin Reinforcement of SPI Adhesive: Enhancing Strength, Antimicrobial, and Flame-Retardant Properties without Excessive Alkali Introduction.

To address the challenges associated with formaldehyde emissions in engineered wood adhesives and simultaneously enhance adhesive properties related to water resistance, fire resistance, and mold resistance, a novel environmentally sustainable biomass-based adhesive was formulated. In this work, kraft lignin was carboxymethylated and then blended with the soy protein isolate (SPI)-based adhesive, the dry and wet shear strength of the plywood bonded by the resultant adhesive was enhanced from 1.10 and 0.63 MPa to 1.73 and 1.23 MPa, respectively, resulting in improvements of 157% and 195%. Carboxymethylated lignin (CML) significantly improved the mold resistance and flame-resistance residual rate of the adhesive and decreased the water absorption rate from 190% to 108%. Furthermore, the adhesive exhibits outstanding flame-retardancy, with self-extinguishing capability rendering it suitable for industrial production. In addition, we also evaluated the performances of resulting adhesives cured with different diepoxides and triepoxides, and the comparisons of the adhesive in this work to commercial urea glue and soy protein-based adhesives were conducted. To our delight, the SPI-10CML adhesive presented comparable or even improved performances, showing its promising practical applications such as for fire doors.

Thermal analysis of fire effects on fire doors using the finite element method

The goal of this paper is to use the finite element method and computer simulation to prove the effectiveness in assessing the fire resistance of building construction elements, specifically on the example of the fire resistance of fire doors. For that purpose, data from the building where fire doors with defined characteristics were installed were used. For simulation purposes, numerical modelling with thermal and structural analysis will be used. In this way, the parameters of the temperature distribution on the fire door and the contact material due to fire will be obtained, as well as the distribution of strain and stresses, which will indicate the fire resistance of the used structure. Computer simulation with numerical modelling offers a number of advantages both in the speed of providing results of a larger number of variants of the simulation model and in the accuracy of the results obtained once the model is calibrated. Also, the mentioned type of predicting the effect of fire can be applied to other elements of the structure of the construction object, which can significantly influence the decision-making that will prevent the negative consequences of the occurrence of a possible fire.

Environmental performance of patient rooms using an integrated approach considering operational energy, daylight and comfort analysis

PurposeThe aim is to holistically assess the environmental performance of windows and analyse how their design and characteristics contribute to the overall performance of the building/space. This study focuses on the performance of windows in patient rooms hosting less mobile people.Design/methodology/approachThis study investigates the life cycle environmental impacts of different glazing types, window frames and fire safety doors at the product level. This article also presents a building-integrated environmental analysis of patient rooms that considers the multiple functionalities of windows by incorporating dynamic energy analysis, comfort and daylighting performance with a life cycle assessment (LCA) study.FindingsThe results indicate that the amount of flat glass is the main contributor to the environmental impacts of the glazing units. As for the patient rooms, global warming shows the most significant contribution to the environmental costs, followed by human toxicity, particulate matter formation and eutrophication. The key drivers for these impacts are production processes and operational energy use. This study highlights the significance of evaluating a wide range of criteria for assessing the performance of windows.Originality/valueAn integrated assessment approach is used to investigate the influence of windows on environmental performance by considering the link between window/design parameters and their effects on energy use/costs, daylighting, comfort and environmental impacts. The embodied impacts of different building elements and the influence of various design parameters on environmental performance are assessed and compared. The environmental costs are expressed as an external environmental cost (euro).

The role of opened fire doors in enhanced heat exchange of long-distance utility tunnels

Due to their distinctive structural attributes, fire compartments in utility tunnels result in regions of increased temperature concentration and thermal dissipation, notably influencing heat exchange phenomena. Investigating airflow diffusion and thermal exchange principles of fire compartments is important when optimizing heat transfer processes in extensive utility tunnels. In this study, we employed numerical simulations and rigorous experimental validation to compare velocity and temperature field attributes between conventional tunnels and those augmented with fire compartments under diverse boundary conditions. The findings revealed that substantial ventilation exchange, reduced cable-based thermal exchange, diminished wall temperatures, and incorporation of opened fire doors are effective measures in improving the thermal environment in utility tunnels. During the summer season, it was observed that the temperature prerequisites were adequately met in a 400-m-long utility tunnel featuring cross-fire compartments at a ventilation rate of 4 air changes per hour (ACH), while tunnels surpassing a length of 600 m required a ventilation rate of 2 ACH, and single-fire compartment tunnels required a ventilation rate of 6 ACH for similar thermal control. Specifically, at a rate of 2 ACH, the temperature in the tunnel exhibited an average reduction of 3.25 °C with the addition of one additional opened fire door. In comparison, a decrease of 1.91 °C was observed when maintaining a rate of 4 ACH. Finally, the airflow characteristics of tunnels with normally opened fire doors were summarized via a finite forced jet model, and the specific ranges of the potential flow core region, characteristic attenuation region and radial attenuation region were obtained.

Analysis of Smoke Control System Performance of High-Rise Multifamily Residential Buildings Using Transient Simulation

In Korea, the general floor plan structure of multifamily residential buildings is such that the vestibules of stairs and fire service-access elevators are typically used together. The lobby of the emergency elevator faces the vestibules of the fire service-access elevators. The smoke control system supplies air for pressurization, and the inlet air discharge device for the exhaust can be exempted from this system. In a 49-story multifamily residential buildings with this structure, the smoke control system is operated at an outside temperature of −10 ℃ and indoor temperature of 20 ℃, and the fire room door is open. The possibility of the vertical spread of smoke owing to changes in the open areas of windows and escape elevator doors was analyzed. When the windows are closed, the vertical spread of smoke through the emergency elevator shaft and staircase may occur under both upper and lower fire conditions of the neutral zone. In particular, the flow path through the emergency elevator door is the main vertical spread path in the case of a fire below the neutral zone.

GLASS PARTITIONS FOR FIRE PROTECTION IN CONSTRUCTION

The main purpose of fire doors is to prevent the spread of fire, smoke and heat inside a building and to enable the safe evacuation of people. In the event of a fire, they close automatically. There are also sliding doors suitable for operation in the event of a fire alarm. They are equipped with automation systems that allow them to open automatically when a fire is detected, making it easier to evacuate people and allowing faster access for the emergency services. There are many additional factors and solutions associated with fire doors and automatic doors that are worth considering in terms of fire safety. Fire doors can be fitted with alarm and monitoring systems that will automatically open the door when a fire is detected, send a signal to the emergency services and activate other safety systems such as smoke extraction or fire suppression systems. Innovative solutions related to fire doors are now being used, such as thermally active doors that automatically react to a rise in temperature and close in the event of a fire. Door control and monitoring systems are also becoming increasingly sophisticated, enabling remote management and real-time monitoring of door status. The drive components and automation of fire doors are subject to specific requirements, as defined by standards and regulations.

Multisensory integration for topological indoor localization of mobile robots in complex symmetrical environments

Indoor localization is essential for robotic navigation by using different sensors on board. Specifically, visual localization with a single camera is a great challenge in highly symmetric environments (e.g. offices, hospitals or residences), where appearance patterns are repetitive and captures from different locations provide very similar images. To overcome this issue, in this paper, we present a method that integrates multisensory information from an RGB-D camera, a LiDAR and motor encoders. Our approach simultaneously utilizes spatial consistency from a reference topological map and temporal consistency from time-series observations. Inspired by human cognitive perception, we define a two layered topological architecture that encompasses both coarse information of object distributions and structural information with some metric references. Categories of common objects in the environments, such as fire extinguishers or doors, are used as natural beacons. We evaluated our approach in two real-world buildings based on a multi-aisle structure with corridors of very similar appearance. Results demonstrated accurate localization despite the high level of symmetry of the scenario, and how ambiguity was significantly reduced as the agent progressed along its trajectory.

Curing treatments of silica gel for fire-retardant glass by intumescence

Silica hydrogels are used as fire-retardant materials due to the occurrence of intumescence that limits heat and mass transfer. They act as heat-sink, through continuous endothermic condensation reactions, meantime shrinking to a more connected network, towards the correspondent crystalline compound. Which compositions and treatments amplify this phenomenon is still of interest. To this aim, two silica sols containing two different complexing agents: ethylene glycol and glycerol has been prepared and analyzed. The samples were subjected to different treatments to induce gelation and densification: exposure to ultraviolet or microwave or infrared irradiation. Thermogravimetric analysis coupled with differential scanning calorimetry (TG-DSC) and scanning electron microscopy analyses has been also carried out. Moreover, dynamic mechanical spectroscopy (DMS) let to evaluate simultaneously the mechanical and intumescence behavior of the gels at increasing curing times for each type of irradiation. Intumescence of gels occurs up to 200 °C and appears as an endothermal group of peaks visible on the heat-flux DSC curves. DMS analyses let to assess that a MW cured glycerol-containing gel (GL-0-MW 6d) shows a glass transition above 150 °C, measured as the maximum of damping peak. Accordingly, this sample is a good option for the application: a few bubbles nucleate and grow fast at high temperature.Article HighlightsTransparent fire doors contain silica gel, which absorbs heat and releases water by foaming. Two different silica gels were synthetized using different chelating agents.The foaming depends on the reagents used to produce the gel, on the treatments for stabilizing it and also on ageing.Both foaming and consolidation of the gel were studied with thermogravimetric and dynamic-mechanical analysis.

Influence of the door opening on the pressure transient caused by the high-speed subway train passing through the double-track tunnel with the mid-partition wall

Double track tunnel with mid-partition wall is a widely used subway tunnel. In such tunnels, in order to avoid the fire door on the middle partition wall from invading the gauge, the fire door is often removed to form door openings. The existence of door opening connects two parallel tunnels, which affects the aerodynamic effect caused by high-speed subway train passing through the tunnel. In this study, a double track tunnel with mid-partition wall was taken as an example to analyze the aerodynamic effect of high-speed subway train under the door opening conditions, moreover, the surface pressure of two adjacent tunnels and train surface pressure was also analyzed. In addition, the propagation mechanism of pressure wave in open door tunnel was analyzed in detail, and the superposition law of branch pressure wave caused by open door was pointed out. The results indicated that the presence of door openings is beneficial for controlling the peak pressure on the tunnel surface and train surface. For a door opening with a cross-sectional area of 5 m2 (cross-sectional area ratio of 0.116), when the door opening is located 300 m and 700 m away from the tunnel entrance, the peak positive pressure can be reduced by up to 21.9 % and the peak negative pressure can be reduced by 21.1 %. The cross-sectional area and number of door openings have a limited effect on reducing the peak pressure of the tunnel. Compared to the number of door openings, the position of the door opening has a more significant impact on the peak pressure inside the tunnel and on the surface of the train.

Fire resistance of gypsum-sheathed stud walls with an embedded steel door: Validation of a numerical approach

In the present study fire resistance tests of gypsum-sheathed stud walls were carried out and a fire safety steel door was embedded within the wall to address the mechanical interaction in between. A numerical approach was proposed based on coupled computational fluid dynamics/finite element method simulations to predict the temperatures and deformation. Since the heat transfer within the porous materials of the wall is crucial for the structural analysis, the numerical approach considered the conduction, chemical reactions, water vapour transport/phase change and thermal radiation. This detailed consideration showed good agreement to measured data for the wall and the door. It was highlighted, that the deformation of the door was well predicted, however, in the vicinity of the connections between the door and wall (e.g. door lock and bolts), the deformation was under-predicted. This was caused by the damaged connections, which were not considered in the simulation. The same effect was found for the wall. Although the numerical model was able to calculate the deformation behaviour, the predicted values were under-predicted due to the neglected failure of the gypsum boards. Furthermore, the numerical model was able to show the gap formation between the door and the wall with high accuracy.

공동주택의 방화문 방･내화성능 기준 및 유지관리 개선연구

공동주택의 방화문 방･내화성능 기준 및 유지관리 개선연구

Corroboration

AbstractCorroborating evidence supports a proposition that is already supported by other initial evidence. It bolsters or confirms the original body of evidence. Corroboration has striking psychological and epistemic force: It potently affects how people do and should assess the target proposition. This essay investigates the distinctive powers of corroborating evidence. Corroboration does not simply increase the quantifiable probability of the adjudicated claim. Drawing on the relevant alternatives framework, I argue that corroboration winnows remaining uneliminated error possibilities. This illuminates the independence, weight, and non-fungibility of corroborating evidence. I compare corroborating evidence to prudential safeguards, like fire doors, that forfend against non-epistemic harms. I thereby sketch a general, non-quantificational model of risk management. Finally, I turn to legal corroboration requirements and the epistemic significance of corroboration for legal proof.