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This paper aims to present an evaluation of comparative fire resistance on traditional and engineered wood joists used in the construction of floor systems in residential housing.

Fire resistance experiments were carried out on four types of wood joists, namely, traditional lumber, engineered I-joist, castellated I-joist and steel/wood hybrid joist, used in traditional and modern residential construction. The test variables included type of wood joist, support conditions and fire protection (insulation).

Results from these tests indicate that webs of engineered I-joists and castellated I-joists are highly susceptible to fire, and failure generally occurs through the burn-out of the web. In addition, engineered I-joists have much lower fire resistance than traditional solid joist lumber. The application of an intumescent coating on an engineered I-joist significantly enhances its fire resistance and yields a similar level of fire resistance as that of a traditional lumber joist.

The presented fire tests are unique and provide valuable insight (and information) to the behavior and response of four types of wood joists when subjected to gravity loading and fire conditions.

This paper aims to present the results of an extensive experimental programme on the fire behaviour of timber beam-to-column shear connections, loaded perpendicularly to the grain.

The experimental programme comprised tests at normal temperature and loaded fire resistance tests on beam-to-column connections in shear. Twenty-four full-scale tests at normal temperature were performed covering nine different connection typologies, and 19 loaded fire resistance tests were conducted including 11 connections typologies.

The results of the fire resistance tests show that the tested typologies of steel-to-timber dowelled connections reached more than 30 and even 60 minutes of fire resistance. However, aspects such as a wider gap between the beam and the column, reduced dowel spacing, and the presence of reinforcement with self-drilling screws all have a negative influence on the fire resistance.

The experimental programme addressed the fire behaviour of timber beam-to-column shear connections loaded perpendicularly to the grain in a systematic way testing a wide range of common connection typologies significantly enlarging their experimental background.

Prefabricated extruded hollow-core slabs are preferred building components for floor structures in several countries. It is therefore important to be able to document the fire resistance of these slabs proving fulfilment of standard fire resistance requirements of 60 and 120 min found in most national building regulations. The paper aims to present a detailed analysis of the mechanisms responsible for the loss of load-bearing capacity of hollow-core slabs when exposed to fire.

Furthermore, it compares theoretical calculation and assessment according to the structural codes with data derived from a standard fire test and from a thorough examination of the comprehensive test documentation available on fire exposed hollow-core slabs.

Mechanisms for loss of load-bearing capacity are clarified, and evidence of the fire resistance is found.

For the first time, the mechanisms responsible for loss of load-bearing capacity are identified, and test results and calculation approach are for the first time applied in accordance with each other for assessment of fire resistance of the structure.

This paper aims to present a part of a coupled numerical model for prediction the fire resistance of elements in a horizontal furnace. Temperatures calculated inside the timber beam are compared to measured values from the fire test.

The paper presents a part of a coupled numerical model for prediction the fire resistance of elements in a horizontal furnace. The presented part lies in a virtual furnace which simulates temperature environment around tested elements in the furnace. Comparison of results show good agreement in the case when burning of timber is included in the numerical model.

The virtual furnace presented in this paper allows to calculate temperature environment around three timber beams. After validation of the fire dynamics simulator (FDS) model, the temperature conditions are passed to the FE model which solves heat transfer to the tested element. Temperatures inside the timber beam which are solved in software Atena Science are compared to measured temperatures from the fire test. The comparison of temperatures in three control points shows good accuracy of the calculation in the point closer to the heated edge. An inaccuracy is shown in points located deeper in the beam cross-section – below the char layer.

In conclusion, the virtual furnace has a great potential for investigating the thermal behaviour of fire-resistance tests. A huge advantage inheres in the evaluation of the thermal effect throughout the volume of the furnace, which allows an accurate prediction of fire-resistance tests and evaluation of large number of technical alternatives and boundary conditions. However, passing the temperature field from the FDS model into FE model may decrease the level of accuracy. The solution lies in a coupled CFD-FE model. A weakly coupled model including fluid dynamics, heat transfer and mechanical behaviour is under development at Faculty of Civil Engineering, Czech Technical University in Prague. The fluid dynamics part which is presented in this paper is solved by FDS and the thermo-mechanical part is computed by object-oriented finite element model (OOFEM). The interconnection of both software is made owing to MuPIF python library.

The virtual furnace takes advantage of great possibilities of computational fluid dynamics code FDS. The model is based on an accurate representation of a real fire furnace of fire laboratory PAVUS a.s. located in the Czech Republic. It includes geometry of the real furnace, material properties of the furnace linings, burners, ventilation conditions and tested elements. Gas temperature calculated in the virtual furnace is validated to temperatures measured during a fire test.

The virtual furnace has a great potential for investigating the thermal behaviour of fire-resistance tests. A huge advantage inheres in the evaluation of the thermal effect throughout the volume of the furnace, which allows an accurate prediction of fire-resistance tests and evaluation of large number of technical alternatives and boundary conditions.

The virtual furnace has a great potential for investigating the thermal behaviour of fire-resistance tests. A huge advantage inheres in the evaluation of the thermal effect throughout the volume of the furnace, which allows an accurate prediction of fire-resistance tests and evaluation of large number of technical alternatives and boundary conditions. However, passing the temperature field from the FDS model into FE model may decrease the level of accuracy. The solution lies in a coupled CFD-FE model. A weakly coupled model including fluid dynamics, heat transfer and mechanical behaviour is under development at Faculty of Civil Engineering, Czech Technical University in Prague. The fluid dynamics part which is presented in this paper is solved by FDS and the thermo-mechanical part is computed by OOFEM. The interconnection of both software is made thanks to MuPIF python library.

The aim of the research was to investigate the effect of concrete strength on the fire resistance of structures. At first, it may seem contradictory that higher concrete strengths can decrease the fire resistance of building structures. However, if the strength of the concrete exceeds a maximum value, the risk of spalling (the detachment of the concrete surface) significantly.

Prefabricated structural elements are often produced with higher strength. The higher concrete strengths generally do not cause a reduction in the load bearing capacity, but it can have serious consequences in case of structural fire design. Results of two prefabricated elements, namely, one slab (TT shaped panel) and one single layer wall panel, were examined. Results of the specimen with the originally designed composition and a specimen with modified concrete composition were examined, were polymer fibres were added to prevent spalling.

As a result of the experiments, more strict regulations in the standards the author is suggested including more strict regulations in the standards. It has been proved that to ensure the fire safety of the reinforced concrete structures, it is required after polymer fibres even in lower concrete strength class than prescribed by the standard. In addition, during the classification and evaluation of structures, it is advisable to introduce an upper limit of allowed concrete strength for fire safety reasons.

As a result of the experiments, the author suggests including more strict regulations in the standards. It has been proved that to ensure the fire safety of the reinforced concrete structures, it is necessary to require the addition of polymer fibres even in lower concrete strength class than prescribed by the standard. In addition, during the classification and evaluation of structures, it is advisable to introduce an upper limit of allowed concrete strength for fire safety reasons.

During the building designing, it is very important to deal with the fire resistance of the structures. The designed materials for escape routes should be selected to ensure the usability of the structures until the time of escape. Planning affects the glass structures similarly, so these can also be partition walls and load bearing structures, although the latter is less applied on escape routes. The heat protection of the glasses can be improved with heat-protective foils, while fire protection is provided by gel intumescent material.

To research the topic of fire resistance, laboratory experiments were carried out on small-scaled glass elements with thermal protection foil at Budapest University of Technology and Economics at the Department of Construction Materials and Technologies.

Fire protection of small model specimens was tested with blowtorch fire and furnace heat load. During the experiments, six foils were tested. Single pane glass, double layered and triple glazed specimens were tested with blowtorch fire.

Fire protection of small model specimens was tested with blowtorch fire and furnace heat load. During the experiments, six foils were tested. Single pane glass, double layered and triple glazed specimens were tested with blowtorch fire. In case of heat-protected glazing, the foils on the “protected” side of the single pane glass do not have a fire protection effect based on blowtorch fire test. For double glassed specimens, the P35 foil has a perceptible effect, even for the requirements of the flame breakthrough (E, integrity), when the foil is placed on the inner side (position 3) of the second glass layer. The stratification of each triple glazed specimens was effective against blowtorch fire load (3 M, S4&P35), so (EI, integrity and isolation) it can meet the requirements of flame breakthrough and thermal insulation.

The fire resistance of timber structures is heavily dependent on the fire behaviour of the connections between its structural elements. The experimental study presented in this paper aimed to investigate the fire performance of glued-laminated timber beam connections reinforced perpendicular-to-wood grain with self-tapping screws (STS).

Two full-size fire experiments were conducted on glulam beam-end connections loaded in flexure bending. Two connection configurations, each utilizing four steel bolts arranged in two different patterns, were reinforced perpendicular to wood grain using STS. The bolt heads and nuts and the steel plate top and bottom edges were fire protected using wood plugs and strips, respectively. Each connection configuration was loaded to 100% of the ultimate design load of the weakest unreinforced configuration. The test assemblies were exposed to elevated temperatures that followed the CAN/ULC-S101 standard fire time–temperature curve.

The experimental results show that the influence of the STS was significant as it prevented the occurrence of wood splitting and row shear-out and as a result, increased the fire resistance time of the connections. The time to failure of both connection configurations exceeded the minimum fire resistance rating specified as 45 min for combustible construction in applicable building codes.

The experimental data show the effectiveness of a simple fire protection system (i.e. wood plugs and strips) along with the utilization of STS on the rotational behaviour, charring rate, fire resistance time and failure mode of the proposed hybrid mass timber beam-end connection configurations.

This paper aims to investigate the fire performance of composite beams when considering the hogging moment resistance of the fin-plate beam-to-girder joints including the effect of continuity of reinforcements.

Experiments on composite beams with fin-plate joints protected only at the beam ends are conducted. The test parameter is the specification of reinforcement, which affects the rotational restraint of the beam ends. In addition, a simple method for predicting the failure time of the beam using an evaluation model based on the bending moment resistance of the beam considering the hogging moment resistance of the fin-plate joint and the reinforcement is also presented.

The test results indicate that the failure time of the beam is extended by the hogging moment resistance of the joints. This is particularly noticeable when using a reinforcing bar with a large plastic deformation capability. The predicted failure times based on the evaluation method corresponded well with the test results.

Recent studies have proposed large deformation analysis methods using FEM that can be used for fire-resistant design of beams including joints, but these cannot always be applicable in practice due to the cost and its complexity. Our method can consider the hogging moment resistance of the joint and the temperature distribution in the axial direction using a simple method without requirement of FEM.

This paper aims to evaluate fire resistance of carbon fiber-reinforced polymer (CFRP)-strengthened concrete slabs in two forms of unprotected and protected against fire.

To achieve the objective, an unstrengthened and two CFRP-strengthened concrete slabs were first subjected to increasing gravity loading until failure. Subsequently, the unstrengthened concrete slab was placed on a furnace and was subjected to a constant service gravity load and then, the temperature of the furnace was increased according to a standard temperature–time curve until the failure of the slab occurred. This slab was strengthened by CFRP with two different amounts and then, in two cases of unprotected and protected against fire, was tested in accordance with the aforementioned method.

The gravity test results revealed that CFRP strips bonded to concrete slabs increased the load-bearing capacity considerably. So, this method can be suitable for flexural strengthening of concrete slabs. The fire test results showed that because of more load-bearing capacity and subsequently increase in service gravity load, the strengthened concrete slab failed in a short time due to the lack of CFRP resistance against fire. By contrast, the protected specimens resisted the fire in a considerable time. In addition, it was revealed that details of fire protective coating had an important effect on fire resistance duration.

It is notable that in the literature, there is a lack of data on the fire endurance of fiber-reinforced polymer-strengthened concrete slabs alone without any fire protection system. Furthermore, the applicability and effectiveness of a new kind of spray mineral fire protective coatings was evaluated.

This paper aims to present performance comparison of fiber sheet-strengthened reinforced concrete (RC) beams bonded with geopolymer and epoxy resin under ambient and fire conditions.

This study presents experimental results of bending tests at ambient temperature and fire resistance tests on two control beams and eight fiber sheet-strengthened RC beams. The test variables include fiber sheet type (carbon fiber [CF] and basalt fiber [BF] sheet), number of layers of fiber sheet (one and two layers) and adhesive agent type (geopolymers and epoxy resin). Data generated from these tests were used to evaluate and compare the strengthening effectiveness of CF-reinforced polymer (CFRP) and CF-reinforced geopolymer (CFRG) at ambient temperature and under fire exposure conditions.

Test results clearly show that the CFRG system can provide good strengthening effectiveness on RC beams at ambient temperature, as the CFRP system, owing to excellent bond properties of geopolymers. Although geopolymers possess better bonding properties at high temperature than organic matrix, the strengthened beams bonded with geopolymer do not exhibit better fire resistance than that those bonded with epoxy resin, owing to early falling-off of fire insulation. Thus, in CFRG-strengthened beams, relevant measures are to be taken to minimize falling-off of fire insulation to achieve good fire resistance.

The presented results are from unique fire tests and provide valuable insight (and information) on the performance of fiber sheet-strengthened RC beams bonded with geopolymer and epoxy resin under ambient and fire conditions.