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Article
Publication date: 23 August 2022

Naveen Revanna and Charles K.S. Moy

A study on the mechanical characteristics of cementitious mortar reinforced with basalt fibres at ambient and elevated temperatures was carried out. To investigate their effect…

Abstract

Purpose

A study on the mechanical characteristics of cementitious mortar reinforced with basalt fibres at ambient and elevated temperatures was carried out. To investigate their effect, chopped basalt fibres with varying percentages were added to the cement mortar.

Design/methodology/approach

All the specimens were heated using a muffle furnace. Flexural strength and Compressive strength tests were performed, while monitoring the moisture loss to evaluate the performance of basalt fibre reinforced cementitious mortars at elevated temperatures.

Findings

From the study, it is clear that basalt fibres can be used to reinforce mortar as the fibres remain unaffected up to 500 °C. Minimal increases in flexural strengths and compressive strengths were measured with the addition of basalt fibres at both ambient and elevated temperatures. SEM pictures revealed fibre matrix interaction/degradation at different temperatures.

Originality/value

The current study shows the potential of basalt fibre addition in mortar as a reinforcement mechanism at elevated temperatures and provides experimental quantifiable mechanical performances of different fibre percentage addition.

Details

Journal of Structural Fire Engineering, vol. 14 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 24 May 2023

Vijaya Prasad Burle, Tattukolla Kiran, N. Anand, Diana Andrushia and Khalifa Al-Jabri

The construction industries at present are focusing on designing sustainable concrete with less carbon footprint. Considering this aspect, a Fibre-Reinforced Geopolymer Concrete…

Abstract

Purpose

The construction industries at present are focusing on designing sustainable concrete with less carbon footprint. Considering this aspect, a Fibre-Reinforced Geopolymer Concrete (FGC) was developed with 8 and 10 molarities (M). At elevated temperatures, concrete experiences deterioration of its mechanical properties which is in some cases associated with spalling, leading to the building collapse.

Design/methodology/approach

In this study, six geopolymer-based mix proportions are prepared with crimped steel fibre (SF), polypropylene fibre (PF), basalt fibre (BF), a hybrid mixture consisting of (SF + PF), a hybrid mixture with (SF + BF), and a reference specimen (without fibres). After temperature exposure, ultrasonic pulse velocity, physical characteristics of damaged concrete, loss of compressive strength (CS), split tensile strength (TS), and flexural strength (FS) of concrete are assessed. A polynomial relationship is developed between residual strength properties of concrete, and it showed a good agreement.

Findings

The test results concluded that concrete with BF showed a lower loss in CS after 925 °C (i.e. 60 min of heating) temperature exposure. In the case of TS, and FS, the concrete with SF had lesser loss in strength. After 986 °C and 1029 °C exposure, concrete with the hybrid combination (SF + BF) showed lower strength deterioration in CS, TS, and FS as compared to concrete with PF and SF + PF. The rate of reduction in strength is similar to that of GC-BF in CS, GC-SF in TS and FS.

Originality/value

Performance evaluation under fire exposure is necessary for FGC. In this study, we provided the mechanical behaviour and physical properties of SF, PF, and BF-based geopolymer concrete exposed to high temperatures, which were evaluated according to ISO standards. In addition, micro-structural behaviour and linear polynomials are observed.

Details

Journal of Structural Fire Engineering, vol. 15 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 2 December 2022

Naveen Revanna and Charles K.S. Moy

This paper employs a textile reinforcement strain comparison to study the response of Textile Reinforced Mortars (TRM) strengthened reinforced concrete one-way slab members in…

Abstract

Purpose

This paper employs a textile reinforcement strain comparison to study the response of Textile Reinforced Mortars (TRM) strengthened reinforced concrete one-way slab members in flexure using the finite element method. Basalt TRM (BTRM) is a relatively new composite in structural strengthening applications. Experimental data on BTRMs are limited in the literature and numerical analyses can help further the understanding of this composite. With this notion, Abaqus finite element software is utilised to create a numerical method to capture the mechanical response of strengthened slab members instead of time-consuming laboratory experiments.

Design/methodology/approach

A numerical method is developed and validated using existing experimental data set on one-way slabs strengthened using Basalt TRMs from the literature. An explicit solver is utilised to analyse the finite element model created using calibrated Concrete Damage Plasticity (CDP) parameters according to the experimental requirements. The generated model is applied to extract load, deflection and rebar strains sustained by strengthened reinforced concrete slabs as observed from the experimental reference chosen. The applicability of the developed model was studied beyond parametric studies by comparing the generated finite element tensile strain by the textile fibre with available formulae.

Findings

CDP calibration done has shown its adaptability. The predicted results in the form of load versus deflection, tensile and compressive damage patterns from the numerical analysis showed good agreement with the experimental data. A parametric study on various concrete strength, textile spacing and TRM bond length obtained shows TRM’s advantages and its favourability for external strengthening applications. A set of five formulae considered to predict the experimental strain showed varied accuracy.

Originality/value

The developed numerical model considers strain sustained by the textile fibre to make results more robust and reliable. The obtained strain from the numerical study showed good agreement with the experiment results.

Details

Multidiscipline Modeling in Materials and Structures, vol. 19 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 6 November 2023

Shanglong Fang, Wei Xiao, Kewen Chen and Xuding Song

Resin-based friction materials are the most widely used key materials in industry for braking and transmission. However, the friction coefficient of resin-based friction materials…

Abstract

Purpose

Resin-based friction materials are the most widely used key materials in industry for braking and transmission. However, the friction coefficient of resin-based friction materials significantly decreases at temperatures above 300°C, which reduces their friction performance.

Design/methodology/approach

This study combines elevated-temperature mechanical experiments with friction and wear experiments to explain the thermal degradation resistance performance and temperature recovery performance of resin-based friction materials. It also investigates the influence of friction material strength and worn morphology on the friction coefficient of materials at elevated temperature.

Findings

The experimental results show that the increase in friction coefficient of friction materials below 300°C is mainly due to the increase in worn morphology characterization parameters, and the thermal degradation phenomenon above 300°C is mainly due to the decrease of shear strength of friction film. Basalt fiber can significantly improve the thermal degradation resistance of friction materials. The friction coefficient of basalt fiber-reinforced specimens after thermal degradation reaches 0.421–0.443, which is 19–25% higher than the original. The thermal decay rate is 9.03–11.0%, which is 7.9–9.87% lower than the original. Moreover, the friction coefficient has good cooling recovery performance.

Originality/value

Revealed the thermal degradation mechanism of resin-based friction materials, verified that basalt fibers can improve the thermal degradation resistance of friction materials and provided reference for the development of new friction materials.

Details

Industrial Lubrication and Tribology, vol. 75 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 10 October 2023

Fatma Bakal Gumus and Ahmet Yapici

The purpose of this paper is to investigate the effect of doping element on the structural, thermal properties, mechanical performance and the failure mechanism of hexagonal nano…

Abstract

Purpose

The purpose of this paper is to investigate the effect of doping element on the structural, thermal properties, mechanical performance and the failure mechanism of hexagonal nano boron nitride (h-BN)-reinforced basalt fabric (BF)/epoxy composites produced by hand lay-up and vacuum bagging technique. h-BN particles doped to composite materials increased the tensile, bending and impact strength of the composite at certain rates while 1 Wt. % h- BN addition shows the highest tensile and flexural strength.

Design/methodology/approach

The epoxy resin was doped with h-BN nanopowder at the certain rates (0, 1, 2 and 4 Wt.%) and the epoxy: hardener ratios used in the study were selected as 80%: 20% by weight. Then, with the aid of a roller by hand lay-up method, a mixture of epoxy + hardeners containing nanoparticles and nanoparticle-free were fed onto BFs, 12 layers of each dimension 30 cm × 30 cm. The surplus epoxy resin was moved away from the composite sheets using the vacuum bagging process and left to cure at room temperature for 24 h. ASTM D3039 for tensile, D7264 for three-point bending and D256 for Izod impact test were performed for the mechanical tests. After the tensile test, the morphologies of the fracture surface were examined with a stereomicroscope and various failure mechanisms are highlighted.

Findings

In this study, a series of basalt/epoxy composites with h-BN nanopowders have been prepared to identify the effect of filler ratio on mechanical properties. It has been known from the results of mechanical experiments that the addition of h-BN improves the mechanical performance of materials at a certain rate. The tensile and flexural strengths of h-BN doped composites, increase for concentrations of 1 Wt.% h-BN, but decrease with the increasing content of it. The basalt/epoxy resin composite with higher mechanical properties could be a potential material in the automotive and aerospace industries.

Originality/value

The aim of this study is to contribute to literature within the context of this new combination of composites and their mechanical properties, failure mechanisms. It presents detailed characterization of each composite by using X-ray differaction (XRD), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 10
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 3 September 2019

Pamela Miśkiewicz, Iwona Frydrych and Wojciech Pawlak

The purpose of this paper is to present the influence of modifying the fabric surface made from basalt fibers by the magnetron sputtering of chromium and aluminum layers on its…

Abstract

Purpose

The purpose of this paper is to present the influence of modifying the fabric surface made from basalt fibers by the magnetron sputtering of chromium and aluminum layers on its resistance to contact heat and comfort properties.

Design/methodology/approach

In order to modify the surface of basalt fabric, the process of physical deposition from the gas phase was used. It relies on creating a coating on a selected substrate by applying physical atoms, molecules or ions of specific chemical compounds. The trial of modification was carried out using the magnetron sputtering method due to the material versatility, application flexibility and ability to apply layers on substrates of various sizes and properties.

Findings

The findings obtained regarding the heat resistance to contact heat and thermal insulation (comfort) properties show different values depending on the type of metal deposited and the thickness of coating layer. It was found that the modification of basalt fabric surface at the micrometer level changes the tested parameters.

Research limitations/implications

This paper presents the results of resistance to contact heat and thermal insulation properties only for the twill fabric made of basalt fiber. The surface modification of fabric was carried out using the chromium and aluminum of two values of layer thickness (1 and 5 µm).

Originality/value

So far, no tests have been carried out to modify the surface of fabric made from basalt fiber yarns using the magnetron sputtering method. In addition, it has not been studied, how the modification of fabric affects its resistance to contact heat and thermophysiological properties.

Details

International Journal of Clothing Science and Technology, vol. 31 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 7 September 2015

Rafal Hrynyk and Iwona Frydrych

– The purpose of this paper is to check an applicability of aluminized basalt fabrics for production of gloves protecting simultaneously against thermal and mechanical factors.

Abstract

Purpose

The purpose of this paper is to check an applicability of aluminized basalt fabrics for production of gloves protecting simultaneously against thermal and mechanical factors.

Design/methodology/approach

Six variants of protective gloves were manufactured using two different glove constructions: more simple and cheaper with the anatomical thumb arrangement (model A), and more ergonomic one with so called “distance gussets” (model B). Aluminized basalt fabrics were contained in the back side of all variants and in only one variant of palm side. Then the protective properties against thermal and mechanical factors were measured according to the up-to-date standards.

Findings

The fulfillment of contact heat requirement was achieved for all glove variants at 100°C. Application of aluminized basalt fabrics in the glove back side allowed obtaining the fourth performance level in the case of resistance to small metal splashes and assuring the highest protection against the radiant heat and small metal splashes. Fulfillment of standard requirements for all examined mechanical parameters was achieved and significantly higher values than reqired for the highest performance level were registered.

Research limitations/implications

The further research including upscalling strategy as well as industrial conditions requirements should be taking into account for basalt textiles development. Moreover functionalization of basalt yarns and fabrics seems to be promising feature.

Practical implications

The preliminary utility trials were done and registered results are very promising, shows that this kind of gloves will be cheaper than produced so far and could be used in the glass, welder companies.

Social implications

The basalt textiles applied for protective gloves or other personal protective equipment can ensure safety at work for end users operating in mechanical and thermal risk scenarios.

Originality/value

Up till now the basalt fabrics have not been recognized as a material for the personal protective equipment, they were used mostly for technical purposes.

Details

International Journal of Clothing Science and Technology, vol. 27 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 27 July 2021

Mervin Ealiyas Mathews, Anand N, Diana Andrushia A, Tattukolla Kiran and Khalifa Al-Jabri

Building elements that are damaged by fire are often strengthened by fiber wrapping techniques. Self-compacting concrete (SCC) is an advanced building material that is widely used…

Abstract

Purpose

Building elements that are damaged by fire are often strengthened by fiber wrapping techniques. Self-compacting concrete (SCC) is an advanced building material that is widely used in construction due to its ability to flow and pass through congested reinforcement and fill the required areas easily without compaction. The aim of the research work is to examine the flexural behavior of SCC subjected to elevated temperature. This research work examines the effect of natural air cooling (AC) and water cooling (WC) on flexural behavior of M20, M30, M40 and M50 grade fire-affected retro-fitted SCC. The results of the investigation will enable the designers to choose the appropriate repair technique for improving the service life of structures.

Design/methodology/approach

In this study, an attempt has been made to evaluate the flexural behavior of fire exposed reinforced SCC beams retrofitted with laminates of carbon fiber reinforced polymer (CFRP), basalt fiber reinforced polymer (BFRP) and glass fiber reinforced polymer (GFRP). Beam specimens were cast with M20, M30, M40 and M50 grades of SCC and heated to 925ºC using an electrical furnace for 60 min duration following ISO 834 standard fire curve. The heated SCC beams were cooled by either natural air or water spraying.

Findings

The reduction in the ultimate load carrying capacity of heated beams was about 42% and 55% for M50 grade specimens that were cooled by air and water, respectively, in comparison with the reference specimens. The increase in the ultimate load was 54%, 38% and 27% for the specimens retrofitted with CFRP, BFRP and GFRP, respectively, compared with the fire-affected specimens cooled by natural air. Water-cooled specimens had shown higher level of damage than the air-cooled specimens. The specimens wrapped with carbon fiber could able to improve the flexural strength than basalt and glass fiber wrapping.

Originality/value

SCC, being a high performance concrete, is essential to evaluate the performance under fire conditions. This research work provides the flexural behavior and physical characteristics of SCC subjected to elevated temperature as per ISO rate of heating. In addition attempt has been made to enhance the flexural strength of fire-exposed SCC with wrapping using different fibers. The experimental data will enable the engineers to choose the appropriate material for retrofitting.

Details

Journal of Structural Fire Engineering, vol. 12 no. 4
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 5 February 2021

Alwyn Varghese, Anand N., Diana Andrushia and Prince Arulraj

Aim of this research work is to examine the stress–strain behavior and modulus of elasticity of fiber-reinforced concrete (FRC) exposed to elevated temperature. The purpose of…

Abstract

Purpose

Aim of this research work is to examine the stress–strain behavior and modulus of elasticity of fiber-reinforced concrete (FRC) exposed to elevated temperature. The purpose of this paper is to study the effect of standard fire exposure on the mechanical and microstructure characteristics of concrete specimens with different strength grade.

Design/methodology/approach

An electrical bogie hearth furnace was developed to simulate the ISO 834 standard fire curve. Specimens were exposed to high temperatures of 821°C, 925°C and 986°C for the duration of 30, 60 and 90 min, respectively, as per standard fire curve. Peak stress, peak strain, modulus of elasticity and damage level of heated concrete specimens were evaluated by experimental investigation. SEM-based microstructure investigation has been carried out to analyze the microstructure characteristics of heated concrete specimens.

Findings

The results revealed that carbon fiber reinforced concrete was found to be better than the FRC made with other fibers on improving the modulus of elasticity of concrete. An empirical relationship has been established to predict the modulus of elasticity of temperature exposed specimens with different type of fiber and grade of concrete. In comparison with low melting point fibers, high melting point fibers exhibited higher modulus of elasticity under all tested conditions. Surface damage and porosity level of concrete with carbon and basalt fibers were found to be lower than other FRC.

Originality/value

Empirical relationship was developed to determine the modulus of elasticity of concrete exposed to elevate temperature, and this will be useful for concrete design applications. This research work may be useful for finding the residual compressive strength of concrete exposed to elevate temperature. So that it will be helpful to identify the suitable repair/retrofitting technique for reinforced concrete elements.

Details

World Journal of Engineering, vol. 18 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 27 May 2014

Akram Hassan Mohammed Ali and Weidong Yu

The purpose of this paper is to investigate thermal protection provided by the fire fighting fabric systems with different layer under high-level thermal hazards with a typical…

Abstract

Purpose

The purpose of this paper is to investigate thermal protection provided by the fire fighting fabric systems with different layer under high-level thermal hazards with a typical temperature range of 800-1,000°C. The purpose of these fabric systems was to provide actual protection against burn injuries using garments worn by industrial workers, fire fighters and military personnel, etc.

Design/methodology/approach

The fabric system was consist of glass with aluminum foil as an outer layer, non-woven basalt, non-woven glass fabric containing NaCl-MgCl2 and Galactitol phase change materials (PCM) which simulate multilayer fire fighter protective clothing system. Thermal protective performance tests were applied for thermal analysis and used as an attempt to quantify the insulating characteristics of fabrics under conditions of flash over temperature. The surface of fire fighting multilayer protective fabric has been characterized using the UV-Vis-NIR (ultraviolet-visible-near infrared) spectrophotometer

Findings

The clothing shows good thermal insulation and high-temperature drop during flash over environment and avoid second degree burn. The current PCM obvious advantages such as the ability to work in high temperature, high efficiency a long period of practical performance.

Originality/value

Using this design of composite multilayer technology incorporating two stages of PCM may provide people with better protection against the fire exposure and increasing the duration time which was estimated to be more than five minutes to prevent burn injuries.

Details

International Journal of Clothing Science and Technology, vol. 26 no. 3
Type: Research Article
ISSN: 0955-6222

Keywords

1 – 10 of 114