Charring depth and charring rate of cross-laminated bamboo slabs exposed to a one-sided standard fire

Purpose Based on heating tests and load-bearing fire tests, this paper aims to discuss the charring rate, the temperature distribution in the section and the load-bearing capacity of structural glued laminated timber beams not only during the heating phase during a 1-h standard fire in accordance with ISO 834-1 but also during the cooling phase. Design/methodology/approach Heating tests were carried out to confirm the charring rate and the temperature distribution in the cross-section of the beams. Loading tests under fire conditions were carried out to obtain the load-deformation behavior (i.e. the stiffness, maximum load and ductility) of the beam. Findings The temperature at the centroid reached approximately 30°C after 1 h and then increased gradually until reaching 110-200°C after 4 h, during the cooling phase. The maximum load of the specimen exposed to a 1-h standard fire was reduced to approximately 30 per cent of that of the specimen at ambient temperature. The maximum load of the specimen exposed to a 1-h standard fire and 3 h of natural cooling in the furnace was reduced to approximately 14 per cent. In case of taking into consideration of the strength reduction at elevated temperature, the reduction ratio of the calculated bending resistance agreed with that of the test results during not only heating phase but also cooling phase. Originality/value The results of this study state that it is possible to study on strength reduction in cooling phase for end of heating, timber structural which has not been clarified. It is believed that it is possible to appropriately evaluate the fire performance, including the cooling phase of the timber structural.

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The charring depth and charring rate of glued laminated timber after a standard fire exposure test

Building and Environment ◽

10.1016/j.buildenv.2008.02.010 ◽

2009 ◽

Vol 44 (2) ◽

pp. 231-236 ◽

Cited By ~ 15

Author(s):

Te-Hsin Yang ◽

Song-Yung Wang ◽

Ming-Jer Tsai ◽

Ching-Yuan Lin

Keyword(s):

Fire Exposure ◽

Exposure Test ◽

Standard Fire ◽

Glued Laminated Timber ◽

Charring Rate

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DOE Standard: Fire protection design criteria

10.2172/10143900 ◽

1999 ◽

Author(s):

Keyword(s):

Fire Protection ◽

Design Criteria ◽

Standard Fire

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The Standard Fire Insurance Policy

Journal of Risk & Insurance ◽

10.2307/250973 ◽

1966 ◽

Vol 33 (1) ◽

pp. 148

Author(s):

C. Daniel Knisely ◽

Max J. Gwertzman

Keyword(s):

Insurance Policy ◽

Standard Fire ◽

Fire Insurance

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

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211026659 ◽

2021 ◽

pp. 036119812110266

Author(s):

Ziyan Ouyang ◽

Qi Guo ◽

Spencer E. Quiel ◽

Clay J. Naito

Keyword(s):

Fire Hazard ◽

Heat Exposure ◽

Element Analysis ◽

Passive Protection ◽

Cooling Period ◽

Flexural Response ◽

Standard Fire ◽

Significant Damage ◽

The Finite Element Analysis ◽

Simultaneous Loss

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.

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Experimental Study on Delaying the Failure Time of In-Service Cables in Trays by Using Fire-Retardant Coatings

Applied Sciences ◽

10.3390/app11062521 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2521

Author(s):

Feng Jiang ◽

Jianyong Liu ◽

Wei Yuan ◽

Jianbo Yan ◽

Lin Wang ◽

...

Keyword(s):

Fire Resistance ◽

Failure Time ◽

Fire Retardant ◽

Resistance Test ◽

Control Group ◽

Engineering Practice ◽

Standard Fire ◽

Oil Storage ◽

Fire Resistance Test ◽

Test Furnace

Improving the fire resistance of the key cables connected to firefighting and safety equipment is of great importance. Based on the engineering practice of an oil storage company, this study proposes a modification scheme that entails spraying fire-retardant coatings on the outer surface of a cable tray to delay the failure times of the cables in the tray. To verify the effect, 12 specimens were processed using five kinds of fire-retardant coatings and two kinds of fire-resistant cotton to coat the cable tray. The specimens were installed in the vertical fire resistance test furnace. For the ISO 834 standard fire condition, a fire resistance test was carried out on the specimens. The data for the surface temperature and the insulation resistance of the cables in trays were collected, and the fireproof effect was analyzed. The results showed that compared with the control group, the failure time of the cable could be delayed by 1.57–14.86 times, and the thicker the fire-retardant coatings were, the better the fireproof effect was. In general, the fire protection effect of the fire-retardant coating was better than that of the fire-resistant cotton.

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Stress–strain relationship model of glulam bamboo under axial loading

Advanced Composites Letters ◽

10.1177/2633366x20958726 ◽

2020 ◽

Vol 29 ◽

pp. 2633366X2095872

Author(s):

Yang Wei ◽

Mengqian Zhou ◽

Kunpeng Zhao ◽

Kang Zhao ◽

Guofen Li

Keyword(s):

Tensile Stress ◽

Compressive Stress ◽

Failure Modes ◽

Axial Loading ◽

Tensile Failure ◽

Stress Strain ◽

Laminated Bamboo ◽

Bamboo Scrimber ◽

Strain Relationship ◽

Strain Model

Glulam bamboo has been preliminarily explored for use as a structural building material, and its stress–strain model under axial loading has a fundamental role in the analysis of bamboo components. To study the tension and compression behaviour of glulam bamboo, the bamboo scrimber and laminated bamboo as two kinds of typical glulam bamboo materials were tested under axial loading. Their mechanical behaviour and failure modes were investigated. The results showed that the bamboo scrimber and laminated bamboo have similar failure modes. For tensile failure, bamboo fibres were ruptured with sawtooth failure surfaces shown as brittle failure; for compression failure, the two modes of compression are buckling and compression shear failure. The stress–strain relationship curves of the bamboo scrimber and laminated bamboo are also similar. The tensile stress–strain curves showed a linear relationship, and the compressive stress–strain curves can be divided into three stages: elastic, elastoplastic and post-yield. Based on the test results, the stress–strain model was proposed for glulam bamboo, in which a linear equation was used to describe the tensile stress–strain relationship and the Richard–Abbott model was employed to model the compressive stress–strain relationship. A comparison with the experimental results shows that the predicted results are in good agreement with the experimental curves.

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