Real Fire Research Articles

Combustion products generated in simulated industrial fires

Studies of firefighter exposure to combustion products have focused predominantly on real or simulated residential structure fires, with few investigations considering industrial fire scenarios. This study measured the atmospheric concentrations of a variety of volatile organic compounds (VOCs), acid gases, and polycyclic aromatic hydrocarbons (PAHs) produced during fires in simulated industrial premises, as well as the deposition of PAHs onto the structural firefighting ensembles worn by the firefighters involved in extinguishment activities. Ingress of these combustion products into the structural firefighting ensembles during firefighting was also measured. Benzene concentrations of up to 23 mg/m3 and total PAH concentrations ranging from 1.7 to 8.6 mg/m3 were observed in personal air samples collected outside the structural firefighting ensembles, as well as a variety of acid gases including hydrogen chloride and hydrogen cyanide. Most combustion products detected outside the structural firefighting ensembles were also detected inside the ensembles, although often at much lower concentrations. The degree of protection observed was not uniform across all the combustion products investigated, with lower levels of protection found for gaseous combustion products such as benzene, xylene, hydrogen cyanide, and hydrochloric acid as compared with PAHs. Deposition of a variety of PAH compounds was observed on the outer surface of the structural firefighting ensembles, with total PAH concentrations ranging from 161 to 347 ng/cm2. While similar combustion products are involved in firefighter exposures during residential and industrial fires, deposition rates of PAHs, may be substantially higher during industrial firefighting. This research provides evidence supporting fireground decontamination measures for management of contamination of structural firefighting ensembles and equipment worn or carried by firefighters during firefighting activities. Further research is required to investigate the potential for dermal deposition of PAHs during actual industrial fire responses, and characterize which stages of fire and firefighting operations contribute the most to firefighters’ exposure to particular contaminants.

The application efficiency of intumescent coatings for power cables of safety systems of nuclear power plants under fire conditions

Introduction. The reliable operation of safety systems, that allows for the failure of no more than one safety system component, entails the safe shutdown and cool-down of an NPP reactor in the event of fire. However, the co-authors have not assessed the loss of performance by an insulating material, treated by intumescent compositions and used in the power cables of the above safety systems exposed to the simultaneous effect of various modes of fire and current loads.Goals and objectives. The purpose of the article is the theoretical assessment of the application efficiency of intumescent fire-retardant coatings in power cables used in the safety systems of nuclear power plants having water-cooled and water-moderated reactors under fire conditions. To achieve this goal, the temperature of the outer surface of the insulation and the intumescent fire-retardant coating was analyzed depending on the mode of fire. Theoretical foundations. A non-stationary one-dimensional heat transfer equation is solved to identify the temperature distribution inside the multilayered insulation and the fire-protection layer of a conductive core.Results and their discussion. The co-authors have identified dependences between the temperature of the outer surface of the insulation and the fire retarding composition of the three-core cable VVGng (A)-LS 3x2.5-0.66, on the one hand, and the temperature of the indoor gas environment for three standard modes of fire and one real fire mode. It is found that before the initiation of the process of destruction of the insulation material, the intumescence of the fire-retardant coating occurs only in case of a hydrocarbon fire. Under real fire conditions, the maximal insulation melting time before the initiation of intumescence of the fire-retardant coating at the minimal temperature of intumescence is 4.75 minutes, while the maximal time period from the initiation of destruction of the insulation material to the moment of the insulation melting is 6.0 minutes.Conclusions. An experimental or theoretical substantiation of parameters of intumescent fire retardants, performed using standard modes of fire, has proven the potential loss of operational properties by insulating materials of power cables, used in the safety systems of nuclear power plants, in case of a real fire. Therefore, it is necessary to establish a scientific rationale for the efficient use of fire retardants in the above cables with regard for the conditions of a real fire.

Experimental study on influence of air gap on upward flame spread over discrete fuel

In a real fire scenario, the distribution of fire loads may not be continuous. In this paper, PMMA blocks (8 cm × 10 cm × 1 cm) are used as experimental materials to carry out upward flame spread experiments with different air gaps (0–18 cm) to analyze changes in burning rate, flame shape, flame height and pyrolysis front position. It is found that as the air gap increases, the burning rate and flame height both increase first and then decrease, and the turning point of this trend is predicted to be between 6 and 8 cm. In addition, it is founded that the pyrolysis reaction is accelerated due to the additional air entertainment provided by the air gap when the pyrolysis front passes through the air gap. However, this effect becomes insignificant for a larger air gap.

Application of the Framework for Fire Investigations in Informal Settlements to large-scale real fire events – Consideration of fire formation patterns, fire spread rates and home survivability

In recent years, there has been a growing number of projects on informal settlement (IS) fire research, which has been primarily focused on understanding the fire dynamics in IS through full-scale experiments. However, much less is known about real IS fire incidents. Recently, a Framework for Fire Investigations in Informal Settlements (FFIIS) was developed. However, the FFIIS has not been applied to real IS fire incidents yet. This paper seeks to conduct fire investigations by applying the FFIIS to three real fire events. One of them was recorded by a CCTV camera and was analysed in depth in previous work. The video footage was used to benchmark the findings obtain using the FFIIS. The application of the FFIIS allows one to develop hypotheses that more accurately define the area of fire origin and pattern formation sequence. This implies that the fire pattern for large post-flashover fires in ISs can be treated as wildland fires pattern, as proposed by the FFIIS. Additionally, spread rates and the impact of dwellings’ separation distances, in these incidents, are studied. Understanding the limitations and the quality of the information that can be obtained when applying the FFIIS is fundamental to improve the guidelines proposed.

Огнезащита стальных и железобетонных конструкций производственных зданий и сооружений

Variants of progressive solutions for the use of efficient fire protection means for steel and reinforced concrete structures of the industrial buildings and structures are considered for the purpose of increasing the actual fire resistance and ensuring the requirements of fire safety norms. Distinctive features of the temperature regimes in the initial phase of a real fire from a standard fire were established when assessing the fire resistance of building structures. It is proposed to use such standardized temperature regimes of fire for assessing the fire resistance of building structures, as standard — in the industrial buildings; temperature regime of hydrocarbons combustion — for oil and gas, petrochemical enterprises, offshore stationary platforms; tunnel temperature regime — in the road and railway tunnels. Considering the operating conditions and performance of work on fire protection, the degree of aggressiveness of the environment, the structural and methodological scheme was developed for selecting passive fire protection for steel structures. Recommendations are given on limiting the use of intumescent paints for load-bearing steel structures involved in the overall stability of buildings, with the required fire resistance limit of no more than 30 minutes. To calculate the temperature over the section of the structure during its heating, the dependences of the change in the coefficients of thermal conductivity and heat capacity of fire-retardant linings under fire were obtained. Experimental studies were conducted related to the fire resistance of reinforced concrete floor slabs and slabs with an external reinforcement system based on the carbon composite material with various types of fire-retardant materials. The issue of protecting the lining blocks of road and railway tunnels from brittle (explosive) destruction of concrete in a fire is considered. It is experimentally confirmed that the addition of polypropylene fibers to the concrete mixture replaces the use of fire protection for the tunnels enclosing structures.

Towards Building Intelligent Robotic Systems to Enhance the Safety of Firefighters

Firefighting robot is a human developed robot to safeguard human’s life. Nowadays, the accidents happening during the fire extinguishing is uncountable. The main role of the proposed robot is to detect the fire, to move towards the fire automatically, to move at any direction to extinguish the water and to send a notification to the nearest fire station. The automatic robot movement is fully controlled by a programmable ESP32. The automatic robot which is in a form of vehicle like will move right, left, front and back to detect and extinguish fire. The firefighting robot equipped with a camera is used to capture the live moment happening at a particular time. The live recording from the camera is sent to the nearest fire station which is already programmed. This recording helps the real fire fighters to know the intensity of the fire and they can plan accordingly to equip themselves. Cloud technology is used to send live recording to real fire fighters to identify the intense of the fire. The exact location of where the fire has happened is also sent to enable firefighters to arrive at the location very quickly.

Vulnerability of Drop Ceilings in Roadway Tunnels to Fire-Induced Damage

Roadway tunnels often include a reinforced concrete drop ceiling that is hung from the liner to create a plenum that facilitates ventilation and houses utilities. Drop ceiling panels are lightweight compared with the much thicker tunnel liner and can experience significant damage from a fire on the roadway below. This paper examines the flexural response of drop ceiling panels in two representative tunnels to standard fire curves as well as several realistic fires due to vehicular accidents. Standard fire demands as per the Rijkswaterstaat and ASTM E1529 fire curves are uniformly applied to the ceiling panels, and heat exposure contours for typical vehicle fires with heat release rates of 30, 100, and 200 MW are generated from the software CFAST. The finite element analysis software SAFIR is used to evaluate the thermo-mechanical behavior of the ceiling panels when subjected to various thermal demands from the fire below. The analysis results indicate that drop ceiling panels are highly vulnerable to fire-induced damage and potential collapse both during a fire’s active heating phase (from simultaneous loss of capacity and restraint of thermal expansion) and during the subsequent cooling period (from tension that develops when the permanently deformed panel thermally retracts). The potential for fire-induced damage or collapse of the drop ceiling panels can be mitigated by reducing the fire hazard, removing the drop ceiling, or enhancing the fire resistance of the panels via the application of passive protection or structural hardening.

Disproportionate collapse of steel-framed gravity buildings under travelling fires

Observations from realistic fires have revealed that a fire tends to “travel” across the floors rather than burning simultaneously for the duration. However, the collapse mechanism and mitigation measures of structures under travelling fires are still not well understood. This paper investigates the disproportionate collapse behaviour of three-dimensional steel-framed gravity buildings subjected to travelling fires. The effect of fire curves (burning rate) and fire spreading speeds on the collapse behaviour is first studied. The effectiveness of using fire protections and bracing systems in preventing collapse is examined. It is found that the duration of the heating phase has a great effect on whether a building collapses or not, and the building may collapse during the cooling phase. A “long-cool” fire curve (slow burnig rate) is more dangerous than mild (average burning rate) and “short-hot” fire curves (fast burning rate) since the former causes a higher temperature in the structure. The fire travelling speed significantly affects the failure sequence of columns, range of damage and collapse mode of structures. For the structure analysed, a slow travelling fire (e.g. 2.5 mm/s) may lead to a partial collapse mode confined around the fire-affected region, but a global collapse in a wider range may occur in a fast travelling fire (e.g. 10 mm/s). A higher level of fire protection may prevent the collapse of structures, but may also lead to collapse in the cooling phase due to the delayed increment of temperatures in the heated members. The collapse time of a protected structure under a travelling fire is longer than the fire-resistance rating of its components (up to 130 min). Application of bracing systems (horizontal, vertical or combined) can prevent collapse of structures under a slow travelling fire, but not for a fast travelling fire. It is recommended to consider the possible fire scenarios when determining the fire-resistance rating, and increase the fire-resistance rating of components to 3 h to prevent collapse under a travelling fire with a “long-cool” fire curve. The beam-to-column connections should possess a sufficient tension and compression resistance, which may be equal to 100% and 50% of the yielding capacity of beams, respectively.

Towards Understanding Fire Causes in Informal Settlements Based on Inhabitant Risk Perception

Informal settlements (ISs) are a high-risk environment in which fires are often seen. In 2019 alone, 5544 IS fires were reported in South Africa. One of the main problems, when investigating an IS fire, is determining the fire cause. In the last 15 years, approximately 40% of the fire causes were classified as ‘undetermined’ in South Africa. Furthermore, the cases where the fire causes have been determined, do not provide the necessary information to comprehend why the fire started. This paper seeks to gain better insight with respect to fire causes by analysing the fire risk perception of IS inhabitants. To this end, a survey that was conducted in 2017, consisting of data from 2178 IS households, that were affected by a large-scale fire, was analysed. The survey consisted of questions relating to the fire risk perception with regards to the settlement in general, to the inhabitants’ own household, and about measures that could reduce fire risk. The analysis suggests that (a) the survey’s risk target had a strong influence on risk perception, (b) the inhabitants’ fire risk perception of their settlement is similar to that of firefighters in previous research, (c) the risk mitigation demands are more focused on decreasing the consequences of the fire than on the occurrence of a fire event, (d) the national fire statistics are not capturing the causes of real fire incidents, and (e) improvements to the documentation process after a fire event could provide critical information for the implementation of prevention measures.

Fire resistance of 3D printed concrete composite wall panels exposed to various fire scenarios

PurposeFire safety of a building is becoming a prominent consideration due to the recent fire accidents and the consequences in terms of loss of life and property damage. ISO 834 standard fire test regulation and simulation cannot be applied to assess the fire performance of 3D printed concrete (3DPC) walls as the real fire time-temperature curves could be more severe, compared to standard fire curve, in terms of the maximum temperature and the time to reach that maximum temperature. Therefore, this paper aims to describe an investigation on the fire performance of 3DPC composite wall panels subjected to different fire scenarios.Design/methodology/approachThe fire performance of 3DPC wall was traced through developing an appropriate heat transfer numerical model. The validity of the developed numerical model was confirmed by comparing the time-temperature profiles with available fire test results of 3DPC walls. A detailed parametric study of 140 numerical models were, subsequently, conducted covering different 3DPC wall configurations (i.e. solid, cavity and rockwool infilled cavity), five varying densities and consideration of four fire curves (i.e. standard, hydrocarbon fire, rapid and prolong).Findings3DPC walls and Rockwool infilled cavity walls showed superior fire performance. Furthermore, the study indicates that the thermal responses of 3DPC walls exposed to rapid-fire is crucial compared to other fire scenarios.Research limitations/implicationsTo investigate the thermal behaviour, ABAQUS allows performing uncoupled and coupled thermal analysis. Coupled analysis is typically used to investigate combined mechanical-thermal behaviour. Since, considered 3DPC wall configurations are non-load bearing, uncouple heat transfer analysis was performed. Time-temperature variations can be obtained to study the thermal response of 3DPC walls.Originality/valueAt present, there is limited study to analyse the behaviour of 3DPC composite wall panels in real fire scenarios. Hence, this paper presents an investigation on the fire performance of 3DPC composite wall panels subjected to different fire scenarios. This research is the first attempt to extensively study the fire performance of non-load bearing 3DPC walls.

The effects of an historical fire on a porous calcarenite from an industrial-archaeological building in the south of Italy

The effects of an historical fire were studied on a porous calcarenite coming from an historic building located in Southern Italy. Changes of material properties were investigated on the masonry blocks affected by fire in comparison with the sound stone. They were also compared with thermally induced degradation under controlled heating in laboratory conditions.The stone was affected by a pronounced aesthetical damage consisting of gray and red discoloring. This was the effect of mineralogical-chemical phase transitions, which were detected by diffractometric and thermal analyses. The transformation of goethite to hematite accounted for changes from the original pale yellow color to red. Gray discoloring was found related to burning of organic matter and formation of magnetite. Damage on the stone microstructure was detected by SEM in the form of micro-cracks. It was also investigated through non-destructive ultrasonic propagation velocity tests, which recorded velocity decreases between 6% and 26%. Microfissuring left almost unchanged the bulk density and porosity measured by buoyancy and saturation techniques, as well as the mechanical properties. The latter were assessed by uniaxial compressive tests. A combined experimental protocol, including colorimetry, non-destructive testing and mechanical testing was used to compare the samples conditioned at high temperature in a laboratory environment with those affected by the real fire. The results allowed to estimate that the maximum temperatures within the stone during fire were under 600 °C, up to 300 °C at a depth of about 8 cm.High porosity of the stone accounts for a limited stone damage at microstructural level and consequent low effects on physical-mechanical properties. On the contrary, in the presence of macrocracking due to the thermal shock experienced by the stone in some areas during fire, an UPV decrease of approximately 40% and significant strength reductions between 46 and 55% were found.

Investigation of bus evacuation flow rates for tunnel fire quantitative risk assessment

ABSTRACT To increase the knowledge of bus evacuation in tunnel fire scenarios, we investigated the bus evacuation flow rate in the event of a tunnel fire, starting with a video analysis of the 2012 Hsuehshan tunnel fire in Taiwan, to gain a preliminary understanding of an actual bus evacuation flow rate. Two evacuation situations were manifested with different flow rates: the first one in which bus passengers non-urgently evacuated as in the case of a daily bus experience (the first seven evacuees, 0.28 PPS (Person Per Second)) and another situation in which passengers feel the urgency to evacuate (the next twelve evacuees, 0.67 PPS). Based on the investigation of the real fire incident, we conducted a bus evacuation experiment and a bus alighting observation. And the results of flow rates of normal exit were within 0.69–0.88 and 0.21–0.48 PPS, respectively. These results were similar to the actual flow rates in the two assumed evacuation situations in the Hsuehshan tunnel fire incident (nonurgent and urgent), respectively. Our approach can provide a viable approach to describe evacuation flow rates during tunnel fires. Moreover, using the flow rate of the normal alighting situation was preferable for highly reliable tunnel fire safety evaluation.

Study on thermo-mechanical coupling method of ship cabin with ceiling vent under fire condition

Objectives The performance analysis of ship cabin steel structures in fire situations is fundamental to structural fire resistance design. Compared with research conducted under traditional standard fire conditions, research based on the real fire temperature field can more accurately analyze the mechanical response behavior of cabin structures. Aiming at an open cabin (i.e. engine room) structure, a fire-heat-structure coupling method combining FDS and ANSYS is developed. Methods First, the FDS simulation is utilized to obtain the temperature information of the inside ship wall exposed to the fire, which is then used as the boundary condition transferred to the structural finite element analysis software ANSYS. Transient thermal analysis concerning the temperature field of the cabin structure is then conducted, and the thermal-structural coupling analysis of the ship cabin structure carried out in a real fire scenario. Results The results of the case study using the proposed method demonstrate that the stress distribution is not uniform due to the uneven temperature distribution. The maximum stress is concentrated at the edge of the cabin, with a value of 19 MPa. The structure does not reach the failure limit after being exposed to fire. Conclusions Compared with the traditional standard fire curve method, the proposed method has two advantages for addressing structural response: the non-uniform elevated temperature of the structure and real fire temperature rise. More attention should be paid to the change in structural internal force caused by non-uniform temperature rise in an open ship cabin.

Predicting Flashover Occurrence using Surrogate Temperature Data

Fire fighter fatalities and injuries in the U.S. remain too high and fire fighting too hazardous. Until now, fire fighters rely only on their experience to avoid life-threatening fire events, such as flashover. In this paper, we describe the development of a flashover prediction model which can be used to warn fire fighters before flashover occurs. Specifically, we consider the use of a fire simulation program to generate a set of synthetic data and an attention-based bidirectional long short-term memory to learn the complex relationships between temperature signals and flashover conditions. We first validate the fire simulation program with temperature measurements obtained from full-scale fire experiments. Then, we generate a set of synthetic temperature data which account for the realis-tic fire and vent opening conditions in a multi-compartment structure. Results show that our proposed method achieves promising performance for prediction of flashover even when temperature data is completely lost in the room of fire origin. It is believed that the flashover prediction model can facilitate the transformation of fire fighting tactics from traditional experience-based decision marking to data-driven decision marking and reduce fire fighter deaths and injuries.

Energy‐based time equivalent approach for evaluating the fire resistance of timber components exposed to realistic design fire curves

SummaryAccording to the concept of performance‐based design, the fire safety design of the timber structures should be focused on the actual design fire, which represents the realistic fire situation in a given building. However, the current prescriptive only provides a method for evaluating the fire resistance of timber components under standard fire. This paper proposed an energy‐based time equivalent approach (EBTEA) for evaluating the fire resistance of the timber components in realistic design fire scenarios. As an alternative, this method was based on the principle of energy equivalence so that the fire resistance design of timber components exposed to realistic fires was standardized, which can make fire resistance rating database available under standard fire exposure and promote performance‐based design. The validity of the method was verified by comparing the predicted values of EBTEA with the existing values obtained from the nonlinear finite element analysis. The proposed method was further simplified by analyzing the key factors of energy equivalence and using nonlinear fitting methods to facilitate the use of designers. The simplified EBTEA can predict equivalent fire resistance of timber components under realistic design fire scenarios.

A Study on Application of Test Bed for Verification of Realistic Fire Management Technology

A Study on Application of Test Bed for Verification of Realistic Fire Management Technology

Real Time Fire detection and Localization in Video sequences using Deep Learning framework for Smart Building

This work presents autonomous electrical fire-detection and localization using computer vision based techniques. The proposed work uses YOLO v2 to extract the electrical fire features more effectively than other conventional and machine learning approaches. This working model is tested on commercial and residential building as well as indoor and outdoor environments. This framework has achieved high detection accuracy and low false alarm rate. Besides, the proposed frame work can be used for early real-time electrical fire detection in surveillance videos and we present experimental results for electrical fire localization in CCTV footage using the deep learning architecture proposed in this work.

РАСЧЕТ ЖЕЛЕЗОБЕТОННОЙ ПЛИТЫ ПЕРЕКРЫТИЯ ПРИ ВОЗДЕЙСТВИИ ПОВЫШЕННЫХ ТЕМПЕРАТУР ПОЖАРА

Розроблено методику чисельного дослідження напружено-деформованого стану залізобетонних конструкцій плит перекриттів з урахуванням нестаціонарних полів температур в арматурі і бетоні за стандартним температурним режимом і температурному режимі реальної пожежі. В рамках методики використовуються характеристики материлов, наведені в ДСТУ-Н Б EN 1992-1-2, а також вихідні дані, необхідні для застосування уточненого методу розрахунку. Ці дані встановлюються шляхом аналізу наявних в літературі експериментальних даних і характеристик матеріалів, наведених в Єврокодах. При оцінці вогнестійкості конструкцій уточненим методом розрахунку враховуються всі фактори, які справляють істотний вплив на напружено-деформований стан конструкції при пожежі. Визначають підвищення і поширення температури в конструкції в заданий момент часу (теплотехнічний розрахунок) і механічну поведінку конструкції (статичний розрахунок), при цьому враховується відповідний сценарій пожежі. Методика ілюструється на прикладі розрахунку на вогнестійкість залізобетонної плити перекриття. Проведено розрахунки з реалізацією пов'язаних термопрочностних завдань в програмному комплексі ANSYS. Проектування залізобетонної плити перекриття виконувалося в модулі Design Modeller програми ANSYS. Потім здійснювалися послідовно розрахунки в модулях TRANSIENT THERMAL і STATIC STRUCTURAL. Бетон і арматура моделюються об'ємними елементами. Підхід не вимагає прив'язки сітки кінцевих елементів до кроку арматури, що дозволяє застосовувати його до завдань з реальними розмірами. У прийнятій моделі бетону поверхня плинності складається з двох пересічних конічних поверхонь Друкера-Прагера. Результати розрахунків добре узгоджуються з представленими літературними експериментальними даними. Використання запропонованої методики дозволяє досить точно оцінити вогнестійкість залізобетонних конструкцій і прогнозувати їх напружено-деформований стан при пожежі.

HelpResponder-System for the Security of First Responder Interventions.

Firefighter’s interventions under dense smoke and flames are hazardous and ideally need an efficient in-advance geo-located actuation plan. The existing communication and sensing technologies should be customized, optimized, and integrated to better know the conditions (flame locations, air condition) before and during the rescue team’s interventions. In this paper, we propose a firefighter intervention architecture, which consists of several sensing devices (flame detectors, carbon dioxide air content) a navigation platform (an autonomous ground wheeled robot), and a communication/localization network (BLE IoT network) that can be used before and during an intervention in rescue or fire extinguishing missions even for indoor or confined spaces. The paper’s key novelty presents our integrated solution, giving some key implementation details and an intensive experimentation campaign in two real firefighter scenarios with real controlled fires. Results carried out in these real indoor scenarios are presented to demonstrate the feasibility of the system. A fire detection system is proposed to improve fire focus in real time and moving in confined spaces with no visibility and physical references. The results obtained in the experimentation show the proposal’s effectiveness in locating the fire focus’s position and orientation reducing time and risk exposure. This kind of location-aware fire integrated systems would significantly impact the speed and security of first responder interventions.

Numerical Simulation of Damage Behaviour of Building Sandstone Exposed to Fire

In this study, numerical simulations of the behaviour of large-size sandstone specimens exposed to wood crib fires were conducted. The developed numerical model, which innovatively considers the reversible quartz expansion behaviour during heating–cooling cycles, can replicate the temperature distributions, cracking behaviours, and strength variations of sandstone samples under various thermal loads (e.g., fires). Results show that the cracking mechanisms during heating and cooling are different, and the spalling is due to their combining effects. During the heating process, tensile stresses are induced mainly inside the sample due to significant expansions of the outer layer. The induced tensile microcracks beneath the surface will be furtherly extended and widened due to the re-distributed local stresses caused by local failures. After the fire, significant tensile stresses appear in the outer part of the sample due to the increased thermal gradients (i.e., volumetric expansions) of the inner part, leading to crack widening on the surface. These widened cracks will coalesce with the heating-induced cracks in the earlier time and boost the fracturing and spalling behaviour until the temperature across the sample reaches an equilibrium state. The findings are essential for understanding the failure mechanism of sandstone during real fire development. The good agreements between lab tests and numerical simulation also reveal the feasibility of using numerical models to predict the fire-induced damage in sandstone elements in architecture.