Enhancing Fire Safety in Commercial Vehicles: Assessing the Efficacy and Advantages of Exploding Fire Extinguishing Balls

Fire incidents in commercial vehicles pose significant risks to passengers, drivers, and cargo. Traditional fire extinguishing systems, while effective, may have limitations in terms of response time, coverage, and human intervention [1]. This study investigates the efficacy of a novel fire suppression technology—the Exploding Fire Extinguishing Ball (EFEB) —as an alternative and complementary fire safety solution for commercial vehicles. The research employs a multidisciplinary approach, encompassing engineering, materials science, fire safety, and human factors analysis. A systematic literature review establishes a comprehensive understanding of existing fire suppression technologies, including EFEBs. Subsequently, this study analyzes the unique features of EFEBs, such as automatic activation, as well as manual activation upon exposure to fire, and their potential to provide rapid, localized, and autonomous fire suppression. The study presents original experimental investigations to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. Experiments include controlled fires in confined spaces and dynamic simulations to emulate real-world fire incidents. Data on activation times, extinguishing capability, and coverage area are collected and analyzed to compare the efficacy of EFEBs with traditional fire extinguishing methods. Furthermore, this research shows the practical aspects of implementing EFEBs in commercial vehicles. A feasibility study examines the integration challenges, cost-benefit analysis, and potential regulatory implications. The study also addresses the impact of EFEBs on vehicle weight, stability, and overall safety. Human factors and user acceptance are crucial elements in adopting new safety technologies. Therefore, this research utilizes an experimental design to assess the performance and effectiveness of EFEBs in various fire scenarios representative of commercial vehicles. This dissertation presents original controlled experiments to emulate real-world fire incidents, including controlled fires in confined spaces and dynamic simulations. The experimental approach ensures rigorous evaluation and objective insights into EFEBs’ potential as an autonomous fire suppression system for commercial vehicles. This includes the perspectives of drivers, passengers, fleet operators, insurance agencies, and regulatory bodies. Factors influencing trust, perceived safety, and willingness to adopt EFEBs are analyzed to provide insights into the successful integration of this technology. The findings of this research will contribute to the knowledge of fire safety technology and expand the understanding of the applicability of EFEBs in commercial vehicles.

A Study on the Awareness of Fire Safety Measures for Users and Staff of Shopping Malls： The Case of Mlimani City and Quality Centre in Dar es Salaam

Shopping malls are accessed by people from all walks of life and, therefore, provision of adequate fire safety measures is equally important. In Dares Salaam, Tanzania, at large construction, use of shopping malls is a relatively new experience, and risks associated with use of shopping malls, such as fire outbreak, are not evident to frequent users. The main purpose of the study is to assess awareness of fire safety measures for users and staff of two shopping malls located in Dares Salaam. The research adopted a case study strategy, and 100 respondents were involved in the study. Both random and purposive sampling methods were used to select respondents for the study. Multiple sources of evidence were used in data collection, namely literature review, observations, questionnaires and interviews. Findings indicate that both shopping malls have in place fairly fire prevention measures with varying degrees. Majority of staff and users indicated that they know fire safety measures but their poor knowledge was reflected in assessing them on diferent equipment and installations, such as foam, hose reel, sprinklers and drenchers. The paper concludes that awarenes of fire safety measure of users and staff of the two shopping malls is relatively low. It is, therefore, recommended that provision of fire safety training and instructions, such as posters for users and seminars for staff of shopping malls, shall be a main focus of shopping malls owners and responsible authorities.

Investigation on Fire Protection System of Highrise Buildings in the Context of Bir Uttam Aminul Haque Avenue in Dhaka, Bangladesh

Rapid high-rise building construction of different occupancies is becoming popular in Dhaka due to its economic gain and functional flexibility. Fire prevention poses a significant difficulty to this type of construction due to its complexity and economic worth as well. Therefore, construction of high-rise building without following the proper fire safety measures, is a common practice at present in the city and it poses a greater threat to urban life considering its associated loss. Even though, most of the owners or authorities do not respect the construction code and the majority of them lack sufficient awareness and basic fire control knowledge and practice. More often, they are unable to comprehend the magnitude and severity of severe fire hazards, and recognize the causes and implementing effective mitigation measures are rare. As a result, the number of fire hazard in high-rise construction is increasing day by day. Hence, investigating the present condition of high-rise buildings (already built) in terms of Fire Protection System is imperative to prevent the upcoming fire hazard. An urban chunk of 33 plots along with Bir Uttam Aminul Haque Avenue, located in Banani, has been chosen for the study area considering its vulnerability to fire hazard. Among these buildings, STAR Tower and HBR Tower, these two high-rise buildings are assessed thoroughly using FRI (Fire Risk Index) Method. The method is semi-quantitative in nature with seventeen parameters associated with fire protection. This assessment represents a scenario in what extent fire codes are being followed in the selected area. It concludes that most of the buildings lack in providing protection against fire hazards for not following the code strictly. This research provides some recommendations which can be followed to improve the fire safety measures in this existing context. It is expected that this research could be a unique addition to firefighting knowledge by contributing to mitigating the consequences of fire related hazards in any densely populated city like Dhaka.

On the Danger of Threats Underestimating and the Resulting Unreliable Assessment of Building Fire Safety

The paper gives an example showing that the utilization of prescriptive rules in some situations can lead to strong underestimation of the real risks and inadequate fire safety assessment of buildings.The issue seems to be very important as the prescriptive rules in many European countries are the only allowed and acceptable by the authority’s method of building fire safety assessment.The building presented in this paper is an exemplary bakery plant consisting of several premises of a different purpose and method of use,e.g.:technical facilities,production depot,distribution and storage spaces,long-term storage cool rooms,etc.The whole building that consists of single-story technological(production and storage)part and(located on two stories)office parts was approved as a singular fire zone with a total usable area of 6280 m2.The technological area includes production facilities,storage depots of raw materials,packages and finished products,as well as cold stores and a number of auxiliary function rooms.In the second(having two stories)part of the building some social rooms,administrative areas and offices are localized.The total height of the building(at the highest point)does not exceed 10.5 m.Due to the Polish regulations the parameters determining the fire-related requirements of individual structural elements of the building(especially in terms of their fire resistance)are the surface area,the average value of the fire-load density and the presence of the risk of possible explosion.The building was designed based on the assumption that the average fire-load density does not exceed the level of 1000 MJ/m2.The analysis and calculations carried out during the exploitation phase of the building confirmed the compatibility with the assumptions adopted,but the actual volume,estimated at the level of 974 MJ/m2 proved to be very close to the limit value.Exceeding of the limit value of 1000 MJ/m2-due to provisions given in a state regulations-would automatically double the formal requirements for the resistance of the structural elements from R30 to R60.When assessing the real risk,especially in case of the large-surface-area buildings with varying ways of use of the premises,the average values of fire-load density may not properly reflect the real threat of fire.This is confirmed in the present facility,where in approximately 47%of the total area of the building the fire-load density doesn’t exceed 100 MJ/m2.Surfaces for which the fire load density exceeds 4000 MJ/m2(in extreme cases,it’s 5644 MJ/m2)represent only about 11%of the total area.It is worth mentioning that the fire-load density exceeding 4000 MJ/m2 due to the national regulations and codes of design would increase the criterion of structural resistance to R240.A completely separate issue is the fact that the oldest part of the building was completed in violation of some basic technical and construction requirements,so that the structure of this part of the building currently does not meet any criteria for fire resistance.This prompted the owner to implement some solutions that will not only lead the property to become fully consistent with the state regulations but also raise the level of security over the required standards,especially in the areas particularly vulnerable to fire.Presented case study shows that the adopted method of determining the requirements for fire resistance,especially based on the average value of fire-load density,in selected cases can lead to significant underestimations and result in incorrect assessment of a building fire safety.

The Analysis of Human Behaviour and Evacuation in a Fire Situation in a Building for Higher Education

The paper presents the analysis of a human evacuation from a higher education building located in Iassy,Romania,by means of engineering techniques to approach fire safety.Because in Romania(as in other European countries)fire safety design of buildings is prescriptive and not performance-based,a fire safety engineering approach arouse great interest in many countries such as the U.S.A.,Australia,New Zealand,England,Sweden,Finland,etc.This paper is based on the assumption of starting a fire in the space of a hall for festivities,located on the ground floor of the building,near two human evacuation routes;We consider two building evacuation scenarios:two exits and,respectively,just one exit(assuming that the second would be accidentally blocked).

Fire Detection Algorithm Based on an Improved Strategy of YOLOv5 and Flame Threshold Segmentation

Due to the rapid growth and spread of fire,it poses a major threat to human life and property.Timely use of fire detection technology can reduce disaster losses.The traditional threshold segmentation method is unstable,and the flame recognition methods of deep learning require a large amount of labeled data for training.In order to solve these problems,this paper proposes a new method combining You Only Look Once version 5(YOLOv5)network model and improved flame segmentation algorithm.On the basis of the traditional color space threshold segmentation method,the original segmentation threshold is replaced by the proportion threshold,and the characteristic information of the flame is maximally retained.In the YOLOv5 network model,the training module is set by combining the ideas of Bootstrapping and cross validation,and the data distribution of YOLOv5 network training is adjusted.At the same time,the feature information after segmentation is added to the data set.Different from the training method that uses large-scale data sets for model training,the proposed method trains the model on the basis of a small data set,and achieves better model detection results,and the detection accuracy of the model in the validation set reaches 0.96.Experimental results show that the proposed method can detect flame features with faster speed and higher accuracy compared with the original method.

Parametric Study on Composite Beams with Web Openings Fire Protected with Reactive Intumescent Coating

When service ducts and cables are required to pass through the structural beams,it is a common practical solution to use composite beams with rectangular or circular openings.The fire safety standards in many countries have recommended design methods for composite beams without openings,while the design method for composite beams with web openings is not addressed yet.Due to the complicated distribution of temperature and stress around the openings in the web of the steel beam,extra complexity has been introduced in determination of the structural capability of the beam and the failure mode in fire.These failure modes generally occur at lower limiting temperatures than the solid beam with same size.It is recognized that the thickness of a reactive coating required to provide a given fire resistance to a composite beam with web openings is affected by the beam’s web thickness,opening configuration,the degree of the beam asymmetry and the structural utilization factor,as well as the nature of the proprietary fire protection itself.Therefore it is necessary that such beams are structurally evaluated taking into account all possible modes of structural failure under both ambient and fire conditions.It is also necessary for additional thermal data to be measured around the web openings and on the web posts from fire tests.The additional thermal data will be used in conjunction with a structural model to determine limiting temperatures of beams with web openings.Steel Construction Institute(SCI)has produced a structural analysis model referenced as report RT1356,which divides a composite beam with web openings into different stress blocks,and then analyses the global bending,vertical shear,local Vierendeel bending,web-post buckling etc.The Association for Specialist Fire Protection(ASFP)recommended the test protocol in the Yellow Book,to determine the temperature distribution around the openings and web post.This paper will discuss a series of fire tests having been carried out in the laboratory of EXOVA Warringtonfire to establish temperature distribution in composite beams with web openings.Test result shows that the distribution of temperature is product specific and strongly affected by opening configuration and opening distance.EXOVA Warringtonfire has also developed a sophisticated calculator,ThermCalc,for analyzing temperature and structural following the method presented in RT1356.Using ThermCalc,parametric study has been carried out,and the effect of load utilization factor,opening size,opening distance,slab depth,decking configuration etc.was investigated.

Fire risk of green building technical components

The concept of the green building as sustainable construction has continuously been studied,developed and distributed.Technologies to realize the green building to use less energy,while protecting the environment and improving the quality of residences have increasingly been used in not only new buildings in the design phase,but also in existing ones to reduce the energy and environment loads.Therefore,the number of green buildings is increasing.However,there are some cases that green building technologies for low energy use,low carbon emissions and pleasant indoor environment violate fire safety standards;so it is imminent to address the issue.Furthermore,unlike continuous studies on development and distribution of green buildings,there are few studies on the issue because of the lack of fire safety awareness of green buildings.Therefore,this study intends to raise the awareness of fire safety awareness of green buildings through theoretical consideration and analysis of cases about green building technologies.

Blended-fuel based EDC combustion model and its application in heptane-ethanol fire simulation

The blended-fuel based eddy-dissipation-concept combustion model was newly developed in the FireFOAM framework, and applied to simulate 30 cm×30 cm heptane-ethanol pool fire. Comparison was made of fire height, centerline temperature against experimental measurements, which shows that they match very well with each other. However, further studies are needed to examine the validation of this model in fire simulations with various scales.

Simulation Emergency Fire Evacuation Model for Nuclear Power Plant

Simulation of egress is vital for minimizing losses during fire disasters, however accurate simulations are scarce and real-life data is hard to come by. In this paper, a Proposed Wireless Fire Evacuation Model (PWFEM) is proposed to simulate fire evacuation process in a short time to minimize evacuee’s exposure to the harmful radiation and fire hazards. The PWFEM simulation realistic by supposing fire scenario at cabined contains electrical cables inside a standard Main Control Room (MCR) in a Nuclear Power Plant (NPP) building. In addition, a new Hybrid Safest Shortest Exit (HSSE) is developed which consists of three stages: safest route based on rules-based technique, evacuees location based on the DV-hop technique [1] and shortest route that depends on Dijkstra technique. The PWFEM Simulations are appreciated to yield a realistic fire scenario by using a telecommunications TCP/IP network in form of server and client sides that help in transfer data inside internal networks in the NPP building. On the server-side, suppose that Consolidated Model of Fire Growth and Smoke Transport (CFAST) fire modeling is applied to simulate the fire scenario in MCR through CFAST model to generate fire products as output data in excel sheets and sends them to the client-side. The client-side then runs HSSE to produce the tree map for safest and shortest routes to help the evacuee for safe exit from his/her location. HSSE can be implemented on evacuee’s watches. From the results, it is concluded that PWFEM can simulate the fire scenario inside MCR, furthermore it is validated that HSEE can be used as an efficient emergency fire evacuation technique that can produce safest and shortest exit route for evacuee in any location inside NPP in very small time. In addition, PWFEM can be used for simulating fire evacuation inside any high-risk buildings and can appreciate yielding any realistic fire scenario with many types of fire sources in different places inside buildings.

Usage of Cool Burning as a Contributor to Bushfire Mitigation

This paper considers and describes the cool burning techniques long utilized by Australian Indigenous people as a contributor to bushfire mitigation. Indigenous fire management involves lighting the “cool” fires in selected areas between March and July, in Australia, during the early dry season. The fires burn gradually, reducing fuel loads and creating fire breaks and not all of the area is burnt. Late in the dry season, when the weather is very hot, the method removes fuel for larger fires while maintaining and protecting habitat for mammals, reptiles, insects and birds. The management of Indigenous cultural fire offers an Indigenous viewpoint for wider control of fire and cultural fire management is an opportunity for collaborations to encourage Aboriginal empowerment with public and private sector organisations. Effective cool burning in contemporary prescribed burning activities can be achieved through implementation of good training, strong partnerships, carefully considered on ground practices and appropriate and effective techniques.

Spontaneous ignition of corrugated cardboard under dynamic high radiant flux

Understanding the response of solid combustibles under high radiant fluxes is critical in predicting the thermal damage from extreme scenarios.Unlike the more moderate radiant fluxes in conventional hydrocarbon fires,extreme events such as strong explosion,concentrated sunlight and directed energy can generate dynamic radiant fluxes at the MW/m^(2) level,creating a unique threat to materials.This study investigates the pyrolysis and spontaneous ignition behaviors of corrugated cardboard by using both experimental and numerical methods,under 10-cm dynamic high radiant fluxes ranging from 0.2 to 1.25 MW/m^(2) for 10 s.The spontaneous ignition process at dynamic high radiant fluxes was recorded and quantified.Two ignition modes were found at the critical radiant flux of 0.4 MW/m^(2),namely hot-gas spontaneous ignition and hot-residue piloted ignition.The latter is not the focus of this paper due to its extremely small probability of occurrence.The research reveals that the increase in flux intensity induces shorter delay times for both pyrolysis and ignition,lower ignition energy density,along with a corresponding rise in the critical mass flux and surface temperature at ignition moment.The simulation results are generally aligned with the experimental findings,despite some divergences may be attributed to model simplifications and parameter assumptions.The work contributes to a deeper insight into material behavior under extreme radiation,with valuable implications for fire safety and hazard assessment.

Evacuating Populations with Special Needs Using Analytical Hierarchy Process (AHP) Method and GIS

The present study is focused on the development of a methodology pertaining to the evacuation plans improvement in a scenario where infrastructures are located in residential settlements that might be threatened by fires;the aforesaid settlements are oftentimes found to be resided by vulnerable population groups, namely elderly people, handicapped people and children. The study pinpoints Evacuation Assembly Points (E.A.P.s) on the outskirts of their settlement and examines the evacuation routes accessibility and safety by way of utilizing Geographic Information Systems (GISs). What is more, our meticulously planned methodology combining quantitative analysis, as well as participatory planning, allows for improve strategies targeted on how to effectively ensure the vulnerable population groups evacuation. The study’s results exhibit how vital it is to integrate technological tools in combination with each community’s partaking in the process of preparing and implementing evacuation plans. The study’s findings furthermore suggest the need to further research the evolution of dynamic evacuation models, which would take the ever-changing and ever-evolving needs of vulnerable population groups into account.

基于FSJ的火灾安全学术地图研究

为了系统认识国际火灾安全研究的全局特征,采用科学知识图谱的方法对Fire Safety Journal(FSJ)中1980-2018年发表的2205篇论文的时间、国家/地区、机构和作者的产出、研究热点聚类以及知识基础与研究演化进行了分析。研究表明:FSJ发文量在时序上呈缓慢的增长趋势,美国、英国、中国在国家层面的产出表现突出,美国国家标准与技术研究院、爱丁堡大学、马里兰大学、中国科学技术大学等是火灾研究的主要机构,HAUKUR INGASON.B.MERCK Y.C.WANG.M.A.DELICHATSIOS、JOSE L.TORERO等是火灾安全研究中的高产学者;火灾安全的研究热点主要集中在4大领域,分别为火灾特性实验结果、火灾安全风险评估与疏散、结构抗火、着火过程与热解,其中火灾安全风险评估与疏散和结构抗火是近年来的重点研究领域。知识基础文献的共被引聚类和文献的突发性探测的分析,展示了火灾安全的高影响力文献分布及其由文献组成的火灾安全研究演化趋势。

Carbon Fibers Decorated by Polyelectrolyte Complexes toward Their Epoxy Resin Composites with High Fire Safety

The achievement of both robust fire-safety and mechanical properties is of vital requirement for carbon fiber （CF） composites. To this end, a facile interracial strategy for fabricating flame-retardant carbon fibers decorated by bio-based polyelectrolyte complexes （PEC） consisting of chitosan （CH） and ammonium polyphosphate （APP） was developed, and its corresponding fire-retarded epoxy resin composites （EP/（PEC@CF）） without any other additional flame retardants were prepared. The decorated CFs were characterized by SEM- EDX, XPS and XRD, indicating that the flame-retardant PEC coating was successfully constructed on the surface of CF. Thanks to the nitrogen- and phosphorous-containing PEC, the resulting composites exhibited excellent flame retardancy as the limiting oxygen index （LOI） increased from 31.0% of EP/CF to 40.5% and UL-94 V-0 rating was achieved with only 8.1 wt% PEC. EP/（PEC8.1@CF） also performed well in cone calorimetry with the decrease of peak-heat release rate （PHRR） and smoke production rate （SPR） by 50.0% and 30.4%, respectively, and the value of fire growth rate （FIGRA） was also reduced to 3.41 kW·m-2- s-1 from 4.84 kW· m-2· s-1, suggesting a considerably enhanced fire safety. Furthermore, SEM images of the burning residues revealed that the PEC coating exhibited the dominant flame-retardant activity in condensed phase via the formation of compact phosphorus-rich char. In addition, the impact strength of the composite was improved, together with no obvious deterioration of flexural properties and glass transition temperature. Taking advantage of the features, the PEC-decorated carbon fibers and the relevant composites fabricated by the cost-effective and facile strategy would bring more chances for widespread applications.

Recent Progress in Two-dimensional Nanomaterials Following Graphene for Improving Fire Safety of Polymer(Nano)composites

The high fire safety of polymer nanocomposites is being pursued by research institutions around the world.In addition to intrinsic flame retardancy strategy,the additive-type flame retardants have attracted increasing attention due to low commercial cost and easy fabrication craft.However,traditional additive-type flame retardants usually need high addition amount to achieve a desirable effect which causes many side-effects on the overall performance of polymer materials,such as deteriorated mechanical property and processability.At present two-dimensional(2D)nanomaterials have also been applied to reduce the fire hazards of polymer(nano)composites with the coupling of barrier function and catalysis as well as carbonization effect.Even though most research work mainly focus on graphene-based flame retardants,more emerging two-dimensional nanomaterials are taking away research attention,due to their complementary and unique properties,mainly including hexagonal boron nitride(h-BN),molybdenum disulfide(MoS2),metal organic frameworks(MOF),carbon nitride(CN),titanium carbide(MXene)and black phosphorene(BP).In this review,except for graphene,the flame retardant mechanism involving different layered nanomaterials are also reviewed.Meanwhile,the functionalization method and flame retardancy effect of different layered nanomaterials are emphatically discussed for offering an effective reference to solve the fire hazards of polymer materials.Moreover,this work objectively evaluates the practical significance of polymer/layered nanomaterials composites for industrial application.

High-fire-safety thermoplastic polyester constructed by novel sulfonate with benzimidazole structure

The flammability of thermoplastic polyesters and the subsequent heavy smoke and severe melt drips formed after ignition are the main obstacles hindering their widespread application. In this study, a novel ionic monomer containing sulfonate and benzimidazole was synthesized and incorporated into the main chain of poly(ethylene terephthalate)(PET, used as a model thermoplastic polyester) by melt copolymerization. The synergetic effect of ionic aggregation and carbonization endowed the obtained copolyester with high melt viscosity and excellent char-forming ability at high temperatures. The copolyester having a monomer content of 8 mol.% easily achieved the Underwriters Laboratories Inc 94(UL-94) V-0 flammability rating without dripping and the limiting oxygen index value reached 33.0 vol.%.In addition, the total smoke production, peak heat release rate,and maximum CO production decreased by 45.2%, 60.5%, and75.0%, respectively, compared with those of PET. In addition,the copolyester was spinnable, and showed greater adsorption efficiency(99.6%) for a cationic dye from solution compared to PET(6.5%), demonstrating the excellent affinity of the copolyester for the cationic dye. The obtained inherently firesafe PET copolyester has great potential for applications in flame retardant textiles, artwork base materials, and decorative materials for transportation applications.

Application of Computer Integration Technology for Fire Safety Analysis

With the development of information technology, the fire safety assessment of whole structure or region based on the computer simulation has become a hot topic. However, traditionally, the concerned studies are performed separately for different objectives and difficult to perform an overall evaluation. A new multi-dimensional integration model and methodology for fire safety assessment were presented and two newly developed integrated systems were introduced to demonstrate the function of integration simulation technology in this paper. The first one is the analysis on the fire-resistant behaviors of whole structure under real fire loads. The second one is the study on fire evaluation and emergency rescue of campus based on geography information technology (GIS). Some practical examples are presented to illuminate the advantages of computer integration technology on fire safety assessment and emphasize some problems in the simulation. The results show that the multi-dimensional integration model offers a new way and platform for the integrating fire safety assessment of whole structure or region, and the integrated software developed is the useful engineering tools for cost-saving and safe design.

High-performance flexible nanocomposites with superior fire safety and ultra-efficient electromagnetic interference shielding

High-performance multifunctional polymeric materials integrated with high fire safety,excel-lent mechanical performances and electromagnetic interference(EMI)shielding properties have great prospects in practical applications.However,designing highly fire-safe and mechanically ro-bust EMI shielding nanocomposites remains a great challenge.Herein,hierarchical thermoplastic polyurethane/cyclophosphazene functionalized titanium carbide/carbon fiber fabric(TPU/CP-Ti_(3)C_(2)T_(x)/CF)nanocomposites with high fire safety and mechanical strength and toughness were prepared through the methods of melt blending,layer-by-layer stacking and thermocompression.The TPU/CP-Ti_(3)C_(2)T_(x)showed improved thermal stability.Moreover,the peak of heat release rate and total heat release of the hi-erarchical TPU sample containing 4.0 wt.%CP-Ti_(3)C_(2)T_(x)were respectively reduced by 64.4%and 31.8%relative to those of pure TPU,which were far higher than those of other TPU-based nanocomposites.The averaged EMI shielding effectiveness value of the hierarchical TPU/CP-Ti_(3)C_(2)T_(x)-2.0/CF nanocomposite reached 30.0 dB,which could satisfy the requirement for commercial applications.Furthermore,the ten-sile strength of TPU/CP-Ti_(3)C_(2)T_(x)-2.0/CF achieved 43.2 MPa,and the ductility and toughness increased by 28.4%and 84.3%respectively compared to those of TPU/CF.Interfacial hydrogen bonding in combination with catalytic carbonization of CP-Ti_(3)C_(2)T_(x)nanosheets and continuous conductive network of CF were re-sponsible for the superior fire safety,excellent EMI shielding and outstanding mechanical performances.This work offers a promising strategy to prepare multifunctional TPU-based nanocomposites,which have the potential for large-scale application in the fields of electronics,electrical equipment and 5 G facilities.

An exploratory study on road tunnel with semi-transparent photovoltaic canopy-From energy saving and fire safety perspectives

Road tunnels consume a large amount of energy,especially in the Canadian cold climate,where the roads are heated electrically or deicing during the winter.For a more sustainable and resilient road tunnel energy system,we conducted an exploratory study on installing a semi-transparent photovoltaic(STPV)canopy at the entrances and exits of a tunnel under a river.The proposed system generates solar-powered electricity,improves thermal and visual conditions,and reduces energy loads.In this study,field measurements of road surface temperature and air temperature were conducted,and numerical simulations with and without STPV were performed to study air and road surface temperatures under different traffic speeds.The field measurements show the road surface temperatures are higher than the air temperature on average.The interior air and road surface temperature were measured to be above 0°C,even though the outdoor temperature is far below 0°C,thus significantly reducing the need for deicing in winter using salts.The simulations show that the air and surface temperatures elevate due to the solar transmission heat through the STPV canopy,thus reducing deicing energy consumption significantly.The fire safety analysis also showed that the proposed system's top opening should be located near the tunnel entrance instead of the canopy entrance for better smoke exhaust during a fire.