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Reactive powder concretes (RPCs) are new concretes characterized by a particle diameter not exceeding 600 µm and very high compressive and tensile strengths. This paper aims to the development and study of the physico-mechanical, elastic properties and durability of an ultra-high performance concrete from materials existing on the Algerian market.

Three mineral additions such as granulated slag, quartz powder and silica fume are incorporated into the cement with 15, 23 and 25 per cent, respectively, in addition to use two different values of steel fiber volume fraction (2 and 2.5 per cent). The results show that the incorporation of 2.5 per cent metal fibers in the formulation of the RPC gives a high compressive strengths of 143.5 MPa at 60 days. The relationship between the relative value and the longitudinal elasto-instantaneous deformations of the RPC to a linear characteristic throughout the relative stress ranges. Also, the modulus of elasticity developed for a fiber-reinforced reactive concrete is greater than that of the unbound fiber.

Results from the current study concluded that the presence of the mineral additions improves the durability of the concretes compared with that not adjuvanted by mineral additions.

It can be possible to manufacture fiber-reinforced reactive powder concretes (RPCFs) with compressive strength exceeding 140 MPa, with an adequate plasticity, despite the simplicity of means and materials and the incorporation of different percentage of metal fiber on the mechanical strength of concretes and its influence on behavior with respect to aggressive environment were achieved.

The purpose of the study was to investigate the spalling phenomenon in ultra-high performance fibre reinforced concrete (UHPFRC) beams on exposure to a standard fire curve (ISO 834) under a sustained load.

The variables in this study were steel fibre dosage, polypropylene (PP) fibres and loading levels. The research investigated seven beams – three of which contained steel fibres with 2 vol.%, another three had steel fibres with 4 vol.% dosage and the seventh beam had a combination of steel fibres (2 vol.%) and PP fibres (4 kg/m³). The beams were tested for 1 h under three loading levels (20, 40 and 60 per cent) based on the ambient temperature ultimate flexural strength of the beam.

Spalling was affected by the loading levels; it exacerbated under the load level of 40 per cent, whereas under the 60 per cent load level, significantly less spalling was recorded. Under similar loading conditions, the beams containing steel fibres with a dosage of 4 vol.% spalled less than the beams with fibre contents of 2 vol.%. This was attributed to the additional tensile strength provided by the excess steel fibres. The presence of PP fibres eliminated spalling completely.

There is insufficient research into the performance of UHPFRC beams at elevated temperature, as most studies have largely focussed on columns, slabs and smaller elements such as cubes and cylinders. This study provides invaluable information and insights of the influence of parameters such as steel fibre dosage, PP fibres, loading levels on the spalling behaviour and fire endurance of UHPFRC beams.

Even though it is widely used, reinforced concrete (RC) is susceptible to damage from various environmental factors. The hazard of a fire attack is particularly severe because it may cause the whole structure to collapse. Furthermore, repairing and strengthening existing structures with high-performance concrete (HPC) has become essential from both technical and financial points of view. In particular, studying the postfire behavior of HPC with normal strength concrete substrate requires experimental and numerical investigations. Accordingly, this study aims to numerically investigate the post-fire behavior of reinforced composite RC slabs.

Consequently, in this study, a numerical analysis was carried out to ascertain the flexural behavior of simply supported RC slabs strengthened with HPC and exposed to a particularly high temperature of 600°C for 2 h. This behavior was investigated and analyzed in the presence of a number of parameters, such as HPC types (fiber-reinforced, 0.5% steel, polypropylene fibers [PPF], hybrid fibers), strengthening side (tension or compression), strengthening layer thickness, slab thickness, boundary conditions, reinforcement ratio and yield strength of reinforcement.

The results showed that traction-separation and full-bond models can achieve accuracy compared with experimental results. Also, the fiber type significantly affects the postfire performance of RC slab strengthened with HPC, where the inclusion of hybrid fiber recorded the highest ultimate load. While adding PPF to HPC showed a rapid decrease in the load-deflection curve after reaching the ultimate load.

The proposed model accurately predicted the thermomechanical behavior of RC slabs strengthened with HPC after being exposed to the fire regarding load-deflection response, crack pattern and failure mode. Moreover, the considered independent parametric variables significantly affect the composite slabs’ behavior.

Present study focuses on scope of developing sustainable heat resistant concrete by adding steel fibre (Sf) and polypropylene fibre (PPf) along with partially replacement of ordinary portland cement (OPC) and natural fine aggregate with fly ash (FA) and granular blast furnace slag (GBFS). Replacement percentages of FA and GBFS were 40% and 50%, whereas Sf and PPf for fibre-added mixes were 1% by volume of concrete and 0.25% by weight of cement, respectively.

An experimental work had been carried out to make comparison between control mix (CM), fibre-added sustainable mix (SCMF) and fibre-added control mix (CMF) with reference to weight loss, mechanical strength (compressive, split and flexure) after exposed to room temperature (27°C) to 1000°C at the interval of 200°C for 4 h of heat curing followed by furnace cooling and then natural cooling. Furthermore, microstructural analysis was executed at 27°C, 400°C and 800°C, respectively.

Colour change and hair line cracks were started to appear at 600°C. Fibre-added control mix and sustainable mix did not exhibit any significant cracks as compared to control mix even at 1000°C. Major losses were occurred at temperature higher than 600°C, loss in compressive strength was about 70% in control mix, while 60% in fibre-added mixes. SCMF exhibited the highest retention of strength with respect to all cases of mechanical strength.

Present study is based on the slow heating condition followed by longer duration of heat curing at target temperature.

Present work can be helpful for the design engineer for assessing the fire deterioration of concrete structure existing near the fire establishment such as furnace and ovens. Building fire (high temperature for short duration) might be the further scope of work.

Concept of incorporating pozzolanic binder and calcareous fine aggregate was adopted to take the advantage pozzolanacity and fire resistivity. To the best of author’s knowledge, there is a scope for fill the research gap in this area.

The purpose of this paper is to develop a coated glass fiber fabric which can be used as the outer shell of firefighters' protective clothing and replace aramid fabric.

The silicone resin with excellent heat resistance was selected as the base solution. Silica nanoparticles, mica powder and ferric oxide were added into the coating solution, which was coated on the glass fiber fabrics. The vertical burning, thermal protective performance (TPP) value, second-degree burn time and water repellency of the coated fabrics were characterized.

Results showed that the dosages of the thickening filler were in the range 4%–6%; the coating solution has good viscosity. The optimal composition of fillers added in the silicone resin is silica nanoparticles 6%, ferric oxide 5% and mica powder 6%. The TPP value of the optimum coated fabric is 413 kW·s/m². The second-degree burn time is 4.98 s, which is obviously higher than that of the original glass fiber fabric (3.49 s) and that of the aramid fabric (3.82 s). The coated fabric has better thermal stability than aramid fabric.

The production cost of this coated glass fiber fabric was much lower than that of the aramid fabric.

This study aims to find out the compressive strength, split tensile strength, flexural strength, bond strength and permeability of steel fibre reinforced concrete subjected to elevated temperatures ranging from room temperature to 800°C. The specimens were exposed to a heating rate of 10°C/min and the target temperature was maintained for 2 hours to achieve a thermal steady state. A total of 210 specimens of plain and fibre reinforced concrete were tested under the test program. Crimped steel fibres were employed in the study at three volume fractions i.e. 0%, 1% and 1.5%. The results show degradation in strength properties with an increase in maximum heating temperature in both plain and steel fibrous concretes. However, when steel fibres are incorporated in the mix, an improvement of fire resistance and crack resistance at elevated temperature was observed. The results indicate a reduced deterioration in residual compressive, split tensile, flexural and bond strengths of fibre reinforced concrete specimens as compared to controlled plain concrete specimens when the temperature was increased from room temperature to 800°C. Residual permeability characteristics of fibre reinforced concrete show better performance than plain concrete.

This paper aims to develop bilayer woven fabrics with different picking sequences with enhanced comfort without any change in the constituent materials.

Six bilayer woven fabrics were produced on Dobby loom with 3/1 twill weave using micro-polyester yarn. Three different picking sequences, i.e. single pick insertion (SPI), double pick insertion (DPI) and three pick insertion (3PI), were used in both face and back layers. The effect of picking sequence on air permeability (AP), volume porosity, thermal resistance and overall moisture management capability (OMMC) of the samples were analyzed.

The results showed that 3PI–3PI picking sequence gives the highest OMMC, AP and thermal resistance in bilayer woven fabrics and the least results exhibited by SPI–SPI picking sequence.

This research uses a bilayer woven system that develops channels and trapes the air causing higher thermal resistance; therefore, applicable for winter sports clothing rather than for summer wear. Developed bilayer woven fabrics can be used in winter sportswear to improve the comfort of the wearer and reduce fatigue during activity.

Authors have developed bilayer fabrics by changing the picking sequences, i.e. SPI, DPI and 3PI of weft yarns in both layers and compared their thermo-physiological comfort properties.

The study aims to review the literatures on the effect of fiber length on the mechanical response of natural fiber composite will help the researchers to know about the perspective of the various natural fibers in making of composite concerning fiber length. The review summarized the work of the other researchers, thereby unambiguously précised suitability of a specific natural fiber for a matrix in use. Thus, one can identify the use of the same fibers–matrix combination to obtain composites with different properties with the control of fiber/matrix interface.

The review work proposes a new kind of diagrammatic representation that expresses the influence of fiber length. This work has not been explored before in this specific format. The chronology of work may help to select natural fibers for use in composites for a specific matrix.

The length of the fiber perception in terms of “critical” length decides the need for pre-treatment process of natural fiber to improve shear stress at the interface for various matrices.

The current review paper attempts to shed light on the association between the fiber length of natural fiber and the mechanical response of natural fiber composite. Moreover, it probes the concepts of critical fiber length as a persuadable factor.

The textile industry has consumed large quantities of water and discharged large volumes of wastewater in the dyeing process. The study aims to characterize self-dyed silk with Rhodamine B (RhB) for fashion applications to reduce textile hazards to the environment and increase the added value of silk.

Bombyx mori was fed with RhB-colored mulberry leaves (1500 ppm). The effects of self-dyeing were investigated via color strength K/S, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope, X-ray diffraction, tensile strength, color fastness to washing, rubbing, perspiration and light.

Self-dyed silk possesses effective coloration and impressive color fastness (4–5/5), higher crystalline index (CrI) (73.26 ± 2.28%), less thermal stability and tenacity, slight change in amino acid composition compared with the pristine and no existence of harmful aromatic azo amines and arylamine salts.

The application of self-dyed silk with RhB dye has expanded new technology into fashion industry, contributing partly to economic growth and adding value to silk in the global supply chain. Besides, the self-dyeing will yield practical values in the reduction of dyeing discharge in textile industry.

Self-dyed silk was characterized for textile applications in comparison with pristine silk in terms of color strength and fastness as well as determined its polymeric properties relating to crystallinity, morphology, chemical composition, tensile properties and thermal stability which have not been investigated before.

Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.