Fire Technology最新文献

{"title":"Correction: Fire Dynamics and Surface Oxygen Measurement During Vertical, Buoyancy-Driven Turbulent Fire Spread","authors":"Dushyant M. Chaudhari, Parham Dehghani","doi":"10.1007/s10694-026-02011-0","DOIUrl":"10.1007/s10694-026-02011-0","url":null,"abstract":"","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10694-026-02011-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149132974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using Multimodal Large Language Models for False Alarm Reduction in Image-Based Fire Detection","authors":"Qie Gao,&nbsp;Haihui Wang,&nbsp;Zhenhai Qin,&nbsp;Linhao Fan,&nbsp;Kang Li,&nbsp;Chong Wang,&nbsp;Qixing Zhang","doi":"10.1007/s10694-026-02000-3","DOIUrl":"10.1007/s10694-026-02000-3","url":null,"abstract":"<div><p>Existing vision-based methods suffer from high false alarm rates in urban flame detection. Applying Multimodal Large Language Models (MLLMs) for secondary filtering shows great potential for reducing false alarms, yet they have high inference latency and are prone to reasoning collapse on negative samples without explicit Chain-of-Thought (CoT) guidance. To overcome these challenges, this study proposes Flash-Cascade, the first sub-second MLLM-based firewall that leverages CoT for efficiently filtering false alarms. We deconstructed the flame detection process into four logical stages (planning, observation, analysis, and judgment), which informed the design of three switchable reasoning modes (Detailed, Quick, and Rapid) to achieve inference acceleration via CoT compression. We fine-tuned Qwen2-VL-7B-Instruct on a multi-granularity instruction dataset via Low-Rank Adaptation. This process decoupled the model’s discriminative capability from long-form text generation, thereby enabling robust performance even without explicit CoT guidance. On our newly constructed benchmark incorporating real-world hard negatives, Flash-Cascade achieves an accuracy of 97.79% and an F1-score of 0.977 in Rapid mode, outperforming the zero-shot baseline by 61.63 percentage points (pp) and 0.515, respectively. Furthermore, it outperforms the state-of-the-art object detector DEIMv2 by 14.64 pp in accuracy. The method exhibits exceptional sample efficiency, converging with only 600 samples and 2 epochs, and improves inference speed by 810% over standard CoT. This study opens new avenues for robust and efficient flame detection in high-interference scenarios.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parametric Analysis and Predictive Modeling for Post-fire Ventilation Following CO2 Fire Extinguishment","authors":"Liu Yang,&nbsp;Bin Zheng,&nbsp;Yinjiao Su,&nbsp;Mingxuan Bai,&nbsp;Weiwei Ge","doi":"10.1007/s10694-026-02008-9","DOIUrl":"10.1007/s10694-026-02008-9","url":null,"abstract":"<div><p>Low-pressure carbon dioxide fire suppression systems, while effectively extinguishing fires in enclosed spaces, create a high-concentration CO₂ environment that poses a significant safety risk to personnel. Designing an efficient post-fire ventilation system to reduce the CO₂ volume fraction to a safe level is therefore of critical importance. This study integrates full-scale fire suppression experiments with PyroSim numerical simulations to investigate the post-fire ventilation process following CO₂ extinguishment. A CFD model was developed, calibrated (turbulent Schmidt number Sc_t = 0.7), and validated against three experimental cases (mean R² = 0.97, RMSE = 0.62). Parametric analysis revealed that the air change rate (ACH) is the dominant parameter governing ventilation efficiency, with 12 h^− 1 recommended as the optimal value. The airflow organization — specifically, a centralized top-supply, bottom-exhaust configuration with vents on the same side — significantly influences the dilution rate by working synergistically with the natural buoyancy-driven stratification of CO₂. Based on the optimized configuration, 27 simulation scenarios spanning nine initial CO₂ volume fractions (14%-54%) and three ACH values (8, 12, 20 h^− 1) were simulated. A predictive model for the safety ventilation duration was derived through log-linear regression (R² = 0.99), providing a quantitative tool for post-fire ventilation system design and risk assessment.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148987031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on Axial Bearing Performance of Reactive Powder Concrete-Filled Square Steel Tube Columns After High Temperature","authors":"Lanqin Wang,&nbsp;Hao Li,&nbsp;Yuzhuo Wang,&nbsp;Ziqing Liu,&nbsp;Sanpeng Cao","doi":"10.1007/s10694-026-01965-5","DOIUrl":"10.1007/s10694-026-01965-5","url":null,"abstract":"<div><p>This study investigated the axial compressive behavior of reactive powder concrete-filled steel tube (RPC-FST) columns after high temperatures. To evaluate the effects of heating duration, spiral stirrup spacing, and steel tube thickness on the post-fire performance of RPC-FST columns, ten specimens were first subjected to high-temperature tests and then subjected to axial compression load tests. The experimental results indicate that all specimens exhibited local buckling failure. The severity of local buckling decreased with increasing steel tube thickness and heating duration, as well as with decreasing spiral stirrup spacing. Compared with the unheated specimens, the specimens with heating times ranging from 140 to 260 min showed a reduction of 2.18–37.46% in the ultimate load and 11.00–38.51% in the elastic stiffness. Under identical heating conditions, the ultimate load increased with increasing steel tube thickness and decreasing spiral stirrup spacing. Specifically, when the steel tube thickness increased from 4 to 10 mm, the ultimate load capacity and elastic stiffness increased by 21.98 and 19.35%, respectively. Moreover, reducing the spiral stirrup spacing from 80 to 40 mm resulted in a 23.30% increase in ultimate load capacity. Based on the experimental results, a calculation method for predicting the axial bearing capacity of RPC-FST columns after high temperature was proposed. The proposed method was evaluated against the experimental results, existing design specifications, and previously reported prediction models, demonstrating its applicability and providing useful references for future research.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148986912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-Time Visibility Enhancement in Fire Scenes Using Edge-Guided Physical Smoke Removal","authors":"Subhradip Das,&nbsp;Diptendu Bhattacharya,&nbsp;Gouranga Mandal","doi":"10.1007/s10694-026-02004-z","DOIUrl":"10.1007/s10694-026-02004-z","url":null,"abstract":"<div><p>The degradation of visibility caused by fire and smoke severely hinders surveillance, leading to delayed decision-making and rescue operations during disasters. Existing smoke and haze removal approaches often struggle with dynamic lighting, heavy smoke, and real-time processing requirements, as they either rely on physical models or deep learning (DL) methods. The enhanced images thus suffer from loss of edge details and over-enhancement in some cases. To address these difficulties, a novel Dark Channel Edge Enhancement Pipeline with CLAHE Fusion (DEEP-CF), a hybrid framework that integrates physics-based and edge-preserving enhancement methods through a multi-stage fusion, is proposed. DEEP-CF uses luminance-based dark channel estimation, edge-aware guided filtering, adaptive rescaling, and dual-stage fusion with CLAHE to enhance both contrast and structure. The implementation ensures real-time performance by leveraging GPUs and achieves up to 44 FPS on 640x480 resolution video streams. Qualitative and quantitative evaluation on the ’Indoor Fire Smoke Dataset’ and real-world scenes demonstrate competitive perceptual quality, smoke intensity reduction, and structural and edge detail preservation compared to other traditional models and improved downstream object detection performance. The results on the evaluation metrics of BIQME, BRISQUE, NIQE, CFI, PSNR, SSIM, EPI, and VIF establish the proposed DEEP-CF pipeline as a favorable perceptual quality enhancer and a computationally efficient, balanced solution for visibility enhancement in dynamic fire and smoke scenes.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148926946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Study on Fire Resistance of Square UHPC Filled Steel Tubular Slender Columns Under Axial Compression","authors":"Yi Jiang,&nbsp;Jingya Wang,&nbsp;Zeyu Chang,&nbsp;Weijie Wang,&nbsp;Zhonghui Zhao,&nbsp;Xin Liao","doi":"10.1007/s10694-026-02003-0","DOIUrl":"10.1007/s10694-026-02003-0","url":null,"abstract":"<div><p>The mechanical response mechanisms of square ultra high performance concrete filled steel tubular (UHPCFST) columns under elevated temperatures differ significantly from those of conventional concrete filled steel tubular (CFST) columns; however, related investigations remain scarce. In this study, a validated thermo-mechanically coupled finite element model was developed to systematically evaluate the effects of section size, slenderness ratio, steel ratio, and load level on the fire resistance of square UHPCFST columns, and to elucidate the distinct load-bearing mechanisms of UHPCFST and CFST columns under fire conditions. The results demonstrate that section size, slenderness ratio, steel ratio, and load level significantly affect fire resistance. Specifically, increasing the section size from 200 to 1000 mm improves fire resistance by approximately 123.5%, whereas increasing the slenderness ratio from 30 to 70 decreases it by 57.4%. Conversely, the effect of material strength is relatively insignificant. At the same load level, UHPCFST columns exhibit 15%–45% lower fire resistance than CFST columns, but demonstrate enhanced load-sharing efficiency between the steel tube and core concrete. Based on the parametric study, a calculation method for predicting the fire resistance of rectangular UHPCFST columns is proposed.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10694-026-02003-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Temperature Distribution in Steel-Concrete Composite Beams with Concrete Hollow Core Slabs with Rectangular Openings Under Fire Conditions","authors":"Laura Mello Camara,&nbsp;Renato Silva Nicoletti","doi":"10.1007/s10694-026-02002-1","DOIUrl":"10.1007/s10694-026-02002-1","url":null,"abstract":"<div><p>The structural contribution of slab in steel–concrete composite beams depends on the interaction between materials. Despite providing procedures for temperature evolution and strength reduction in composite beams with solid slabs, NBR 14,323 does not include specific recommendations for systems that incorporate hollow-core slabs. Towards addressing that knowledge gap, this manuscript reports on a comprehensive parametric numerical investigation of temperature distribution in steel–concrete composite beams that incorporate hollow-core concrete slabs with rectangular openings. Building upon previous research, the study evaluates rectangular openings, expands the range of concrete densities to six classes (1,750-3,000 kg/m³), and increases the numerical database from 60 to 120 thermal models. The expanded database enables a systematic assessment of the combined influence of opening geometry and concrete density on the thermal response of hollow-core slabs and provides new temperature distribution tables suitable for future code development. According to the results, six tables show the temperature variation along the slab depth for densities ranging from 1,750 to 3,000 kg/m³, indicating hollow-core slabs consistently develop higher temperatures than those prescribed by NBR 14,323 for solid slabs of same density. The results also show opening geometry substantially affects the temperature distribution, with differences of up to 85.8 °C between rectangular and circular openings in function of slab layer and fire exposure time. Therefore, both internal geometry and concrete density should be considered for the development of future structural fire design provisions for hollow-core slab systems. The aforementioned tables provide a preliminary technical basis for assessments of the thermal behavior of hollow-core slabs with rectangular openings and may support future improvements to structural fire design provisions for steel–concrete composite beams.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10694-026-02002-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A One-Way Sequential CFD-FEM Model for Assessing the Fire-Induced Thermal Spalling Evolution of Tunnel Lining Concrete","authors":"Tenggen Xiong,&nbsp;Feng Wang,&nbsp;Jixin Liu","doi":"10.1007/s10694-026-02006-x","DOIUrl":"10.1007/s10694-026-02006-x","url":null,"abstract":"<div><p>Tunnel fires pose a serious threat to the operational safety of transportation infrastructure due to the high temperatures that may induce concrete lining spalling and reduce structural integrity. To improve the prediction of fire-induced thermal response in tunnel linings, this study develops a one-way sequential CFD-FEM model, in which the gas temperature predicted by Fire Dynamics Simulator (FDS) is transferred to ABAQUS for transient heat transfer analysis. Based on experimentally established spalling criteria involving temperature, temperature gradient, and heating rate, the framework is used to simulate the spatial and temporal evolution of tunnel lining spalling. Parametric analyses are performed to investigate the influence of concrete strength, heat release rate (HRR), and fire source location on lining temperature distribution and spalling behavior. Under the investigated tunnel geometry, fire scenarios, and adopted spalling criteria, the numerical results predict that higher-strength concrete exhibits earlier and more extensive spalling than normal-strength concrete. Increasing the HRR intensifies the lining temperature and enlarges both the depth and extent of spalling. Off-center fire locations produce asymmetric temperature distributions, causing the spalling region to shift toward the fire source and altering the predicted spalling extent. The proposed framework provides an engineering-oriented approach for evaluating fire-induced tunnel lining spalling under specified fire scenarios, while the quantitative results are applicable to the conditions considered in this study.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Fabric Stretch on the Thermal Protective Performance of Firefighter Clothing: An Experimental and 3D Numerical Analysis","authors":"Sijia Wu,&nbsp;Miao Tian,&nbsp;Jianuo Wang,&nbsp;Yun Su,&nbsp;Jun Li","doi":"10.1007/s10694-026-02005-y","DOIUrl":"10.1007/s10694-026-02005-y","url":null,"abstract":"<div><p>During firefighting operations, movements such as bending elbows and knees induce deformation of the outer shell material, affecting the thermal protective performance (TPP) of firefighter clothing. However, the effects of fabric stretching under different thermal environments and the associated microstructural mechanisms remain unclear. To investigate this, experiments were conducted at four stretch levels (0%, 3%, 6%, 12%) under three thermal conditions (8.5 kW/m² radiant heat, 30 kW/m² flame, 84 kW/m² hybrid heat), measuring fabric structural properties and TPP. Results indicated that stretching reduced fabric porosity and slightly increased thickness, with TPP decreasing more noticeably under low-radiation heat. To elucidate the heat transfer mechanisms, a three-dimensional finite element model incorporating yarn geometry and air pores was developed. Simulations revealed that stretch-induced structural changes enhanced the intrinsic thermal insulation performance (TIP) of the fabric. Parametric analyses further showed that increasing surface convection produced only minor changes in thermal resistance, whereas increasing fiber thermal conductivity resulted in a more noticeable reduction. Combined experimental and simulation results demonstrated that changes in TPP were governed by the competing effects of (i) improved thermal insulation due to increased fabric thickness and (ii) enhanced conductive heat transfer due to increased fiber–sensor contact area. Although stretching increased TIP, the latter effect dominated, resulting in lower TPP values. These findings elucidate the heat transfer mechanisms of stretched fabrics and support TPP evaluation considering fabric deformation. They also provide practical guidance for the design of firefighting suits with adequate ease allowances in body regions undergoing substantial movement, thereby improving firefighter thermal protection and safety.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergistic Suppression of Coal Dust Explosions by a Novel Phosphorus-Grafted Fly Ash Composite: Preparation, Performance, and Mechanism","authors":"Jun Wu,&nbsp;Peng Chen,&nbsp;Bochen Ma,&nbsp;Zhizhen Zhang,&nbsp;HaoYou Zhao","doi":"10.1007/s10694-026-01988-y","DOIUrl":"10.1007/s10694-026-01988-y","url":null,"abstract":"<div><p>Coal dust explosions pose a severe threat to industrial safety, while the large-scale disposal of fly ash (FA) presents a significant environmental challenge. To utilize this industrial solid waste for safety applications, a novel phosphorus-modified fly ash composite explosion suppressant (FA@H₃PO₄) was developed. The suppressant was synthesized via alkali activation pretreatment followed by phosphoric acid grafting. Characterization using SEM, EDS, and FTIR confirmed that the modification effectively increased the surface roughness of FA and successfully introduced phosphorus-containing flame-retardant groups. Explosion suppression performance was evaluated in a visual vertical combustion tube, where FA@H₃PO₄ demonstrated significantly superior performance compared to raw FA. At a concentration of 60 wt%, the modified agent reduced the flame propagation velocity to 2.6 m/s, resulting in a discontinuous “ghost flame” structure; the peak flame temperature was drastically suppressed to approximately 241 °C, compared to 1285 °C for pure coal dust. Furthermore, the addition of 60 wt% FA@H₃PO₄ led to an 80% decrease in maximum explosion pressure (P_max) and a 100% extension of the time to peak pressure. Thermal analysis (TG) reveals that the suppression mechanism relies on a synergistic effect: the physical cooling and barrier function of the fly ash skeleton, combined with the chemical scavenging of free radicals by the grafted phosphorus groups. This study provides a cost-effective and efficient technical pathway for coal dust explosion control.</p></div>","PeriodicalId":558,"journal":{"name":"Fire Technology","volume":"62 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2026-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}