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Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates the behavior of recycled Reactive Powder Concrete (RPC), made from finely ground recycled raw materials and containing a certain percentage of recycled copper (electrical waste copper wire) and steel fibers. This concrete has a relatively low water-to-binder ratio and is composed of cement, fine aggregate, and ultrafine powders, such as quartz powder and silica fume. The properties of Fiber-Reinforced Reactive Powder Concrete (FR-RPC) containing micro-steel fibers, recycled copper fibers, and a mixture of steel-recycled and copper fibers were investigated. A micro-steel fiber RPC (MF1) was used as a reference mix, having 1% steel fibers by volume with 13 mm length and 0.2 mm diameter. Recycled copper fiber RPC (MF2) was prepared utilizing 1% recycled copper fibers by volume, with a diameter of 0.2 mm and a length of 10 mm. In addition, Hybrid FR-RPC (HFR-RPC) samples were prepared by mixing micro steel fibers and recycled copper fibers in proportions of 0.5-0.5% (MF3), 0.4-0.6% (MF4), and 0.3-0.7% (MF5), respectively. The compressive strength, flexural strength, and splitting tensile strength of these FR-RPC mixes were studied. The results displayed that MF3 achieved slightly lower compressive strength, flexural strength, and splitting tensile strength than MF1 and higher than MF2, MF4, and MF5. Although the mechanical strengths of MF3 were marginally lower than those of MF1, compressive strength, flexural strength, and splitting tensile strength were almost the same. Therefore, copper wire waste fibers can be employed along with steel fibers with excellent results. [ABSTRACT FROM AUTHOR]

In the era of environmental concerns, many attempts were proposed to optimize energy efficiency for buildings and consequently reduce their carbon footprint. As a sustainable approach, it is a promising solution to incorporate phase change materials (PCMs) in construction materials (i.e., ultra-high-performance concrete (UHPC)) to increase its thermal storage capacity and reduce the operation energy. However, incorporating microencapsulated phase change materials (MPCMs) into cementitious materials negatively impacts the fresh and hardened properties. UHPC's improved mechanical strength allows for the creation of slimmer and lighter structures, which may result in less demand in concrete manufacturing and fewer emissions. Hence, the properties of UHPC incorporated with MPCMs (MPCM-UHPC) need more investigations. To fill the gap in the literature about the lack of information about MPCM-UHPC performance, this paper provides a comprehensive work to study the mechanical, thermal, and impact resistance properties of (MPCM-UHPC). Proportions of 5% and 10% of MPCMs were incorporated as a replacement of sand by volume. Proportions of 0.5%, 1.0%, and 1.5% of micro steel fiber reinforcement were used as a percentage of the mixture's total volume. The results revealed the importance of fiber reinforcement in compensating for the negative effect of MPCMs inclusion for improving the thermal properties. Increasing the amount of MPCMs enhanced the thermal performance of the produced UHPC panels through the ability to absorb and release the energy during the phase change process. [ABSTRACT FROM AUTHOR]

Polyurethane (PU)-based Mortar (PUM) has a short curing time and high bonding ability as a new potential repair material. However, its low strength significantly limits its application in maintaining civil engineering structures. In this paper, the effect of micro steel fiber (MSF) with different aspect ratio and different dosages on the compressive strength, flexural strength, and elastic modulus of PUM was investigated. The performance of fiber at different embedment depths on the interfacial bond properties between the PU-based mortar mixture and steel fiber was explored through the fiber pull-out test. Additionally, steel fiber’s reinforcing and toughening effects were analyzed, and scanning electron microscopy (SEM) was used to analyze the microstructure of PU-based mortar reinforced with steel fiber. The results showed that the mechanical performance of PUM incorporated with two fiber types up to 3% was significantly improved. The bond strength between the micro steel fiber and PUM mixture improved with the increase in fiber volume fraction in the PU mixture. Similarly, the pull-out load and the pull-out work are increased with the increase in depth, while the interface bond strength is decreased. Additionally, based on the result obtained, the reinforcing effect of MSF in PUM can effectively refine the pores and bridge the crack formation.

Environmental sustainability is described as one that avoids the depletion or deterioration of natural resources, while also allowing for the preservation of long-term environmental quality. By practicing environmental sustainability, we may assist to guarantee that the requirements of today’s population are satisfied without risking the capacity of future generations to meet their own needs in the future. Engineers in the field of concrete production are becoming increasingly interested in sustainable development, which includes the utilization of the locally available materials in addition to using the agricultural and industrial waste in construction industry as one of the possible solutions to the environmental and economic issues. This study investigated the effect of partial substitution of cement with recycled glass powder (0, 15, 20, and 25%) by weight of cement at various ages (on compressive strength) after determining the optimal ratio of replacement. This optimal ratio is used to study its effect on some mechanical properties (such as flexural strength, absorption, and dry density) of reactive powder concrete containing 1% micro steel fiber (SRPC), and furthermore, utilizing steam curing for 5 h at 90°C after hardening the sample directly. Reactive powder concrete (RPC) has been designed with the use of the local cement, silica fume, and super plasticizer with a water/cement ratio of 0.20 in order to achieve a compressive strength of 137.09 MPa at the age of 28 days. When recycled glass powder replacement (20%) was utilized, the findings revealed that the compressive strength of RPC improved by 4.2%, the flexural strength increased by 15.3%, the dry density increased by 0.61%, and the absorption was reduced by 32% at 28 days after the test results were compared to the reference mix.

Self-Compacting Concrete (SCC) is an innovative construction material that flows and compacts under its own weight, making it ideal for complex structures due to its high workability. Micro steel fibers, smaller in size than conventional fibers, have recently been adopted in both research and industry due to their limited effect on workability, which facilitates casting and construction process, alongside their promising contributions to enhancing the mechanical performance of concrete. The mechanical, rheological, and electrical properties of micro steel fiber-reinforced high-strength SCC members were investigated in this study. The testing program included prismatic specimens (100 × 100 x 500 mm3), cubic specimens (150 × 150 x 150 mm3), and cylindrical specimens (100 mm × 200 mm). The micro steel fiber contents considered were 0.0 %, 0.35 %, 0.70 %, and 1.05 % by volume. Test results revealed that the inclusion of micro steel fibers reduced workability, particularly above a 0.70 % fiber content, and resulted in maximum enhancement rates of 13.3 % in compressive strength, 52.4 % in splitting tensile strength, and 13.2 % in flexural strength compared to fiber-free specimens. The toughness index (T 150) was enhanced by up to 40 % at higher fiber volumes. These findings highlight the balance between workability and mechanical improvement provided by micro steel fibers. Bulk electrical resistivity exhibited a clear decreasing trend with increasing fiber content. • A detailed approach of producing high-strength self-compacting concrete was presented. • The impact of using different micro steel fiber contents was elucidated. • Straight micro steel fibers improved mechanical properties of concrete. • The electrical resistivity of micro steel fiber reinforced SCC was investigated. [ABSTRACT FROM AUTHOR]

In the era of environmental concerns, many attempts were proposed to optimize energy efficiency for buildings and consequently reduce their carbon footprint. As a sustainable approach, it is a promising solution to incorporate phase change materials (PCMs) in construction materials (i.e., ultra-high-performance concrete (UHPC)) to increase its thermal storage capacity and reduce the operation energy. However, incorporating microencapsulated phase change materials (MPCMs) into cementitious materials negatively impacts the fresh and hardened properties. UHPC’s improved mechanical strength allows for the creation of slimmer and lighter structures, which may result in less demand in concrete manufacturing and fewer emissions. Hence, the properties of UHPC incorporated with MPCMs (MPCM-UHPC) need more investigations. To fill the gap in the literature about the lack of information about MPCM-UHPC performance, this paper provides a comprehensive work to study the mechanical, thermal, and impact resistance properties of (MPCM-UHPC). Proportions of 5% and 10% of MPCMs were incorporated as a replacement of sand by volume. Proportions of 0.5%, 1.0%, and 1.5% of micro steel fiber reinforcement were used as a percentage of the mixture’s total volume. The results revealed the importance of fiber reinforcement in compensating for the negative effect of MPCMs inclusion for improving the thermal properties. Increasing the amount of MPCMs enhanced the thermal performance of the produced UHPC panels through the ability to absorb and release the energy during the phase change process.

Slurry Infiltrated Fiber Concrete (SIFCON) is a relatively new high-performance material that may be thought of as a high-fiber content version of fiber reinforced concrete. This matrix is comprised of flowing mortar that must penetrate the fiber network implanted in the molds sufficiently. SIFCON combines excellent mechanical properties with a high ductility and toughness grade. SIFCON is utilized in applications that demand a high degree of ductility and energy absorption, most notably seismic-resistant reinforced concrete structures and structures exposed to abnormal or explosive loads. Additionally, pavement overlays, prestressed beam repair, and structural reinforced concrete element restoration have all been effective. The main aim of this study is to determine the effect of hooked-end steel fiber and micro-steel fiber on the strength of SIFCON specimens exposed to flexural and splitting loading. Three volume fractions of steel fiber (8,10, and12) % were used in this investigation. By weight of cement in SIFCON slurry, the proportion of Silica Fume SF substitution was 10%. Flexural strength was determined by testing specimens of (100×100×500) mm, and splitting tensile strength was determined at 7 and 28 days using cylindrical specimens with dimensions (150mm × 300m).. The results obtained from these tests were compared with SIFCON containing micro steel fiber. The test results show superior characteristics of SIFCON containing hooked-end steel fiber, as compared with micro steel fiber. For example, the flexural strength and splitting strength are 24.89 MPa and 10.14 MPa, respectively for SIFCON with 8% hooked-end steel fiber and 17.51 MPa and 9.1 MPa for control specimens with micro steel fiber.

The present research emphasizes on the durability behaviour of hybrid fiber reinforced engineered cementitious composite (HFRECC) through exposure to chemicals environment for 12 months. The structural reinforcing micro-fibers used in this study were polyvinyl alcohol (PVA) fiber, polyester (PLY) fiber, and micro steel (MSE) fiber. Hybridization of micro-fibers was done in two stages; in the first stage, up to 25% of PVA fiber was switched by PLY fiber at a dosage of 5%, 10%, 15%, 20%, 25%. In further investigation, the amalgam of PVA, PLY (polymeric), and MSE (non-polymeric) fibers were used at dosages of 50%, 25% and 25% respectively. The performance of the matrix was assessed on the basis of compressive response, tensile strength, tensile strain capacity, and electrical resistivity (ER) characteristics. The results obtained revealed that the hybridization of micro-fibers enhanced the overall performance of ECC and provided resistance to the movement of detrimental ions through the matrix. [ABSTRACT FROM AUTHOR]

This paper presents the experimental, statistical modeling, and reliability analysis of impact resistance of micro steel fiber reinforced concrete (FRC) incorporated with nano silica (NS) using a drop‐weight impact test. U‐shaped concrete specimens were developed for the experimental work. The result showed that the combined effect of micro steel fiber (SF) and NS led to significant improvement of impact resistance of concrete mixtures, and lower ductility ratios were obtained for specimens with high SF and NS content. A common failure pattern was observed for all the concrete specimens. The response surface methodology models developed to predict the impact resistance of FRC‐NS mixtures showed a high degree of correlation. Due to the variation in the drop‐weight impact test' result, the Weibull distribution (WD) function was employed for advance analysis, and the result revealed that the probabilistic distribution of first crack strength (N1) and failure strength (N2) follows the two‐parameter WD. [ABSTRACT FROM AUTHOR]

Slurry Infiltrated Fiber Concrete (SIFCON) is a relatively new high-performance material that may be thought of as a high-fiber content version of fiber reinforced concrete. This matrix is comprised of flowing mortar that must penetrate the fiber network implanted in the molds sufficiently. SIFCON combines excellent mechanical properties with a high ductility and toughness grade. SIFCON is utilized in applications that demand a high degree of ductility and energy absorption, most notably seismic-resistant reinforced concrete structures and structures exposed to abnormal or explosive loads. Additionally, pavement overlays, prestressed beam repair, and structural reinforced concrete element restoration have all been effective. The main aim of this study is to determine the effect of hooked-end steel fiber and micro-steel fiber on the strength of SIFCON specimens exposed to flexural and splitting loading. Three volume fractions of steel fiber (8,10, and12) % were used in this investigation. By weight of cement in SIFCON slurry, the proportion of Silica Fume SF substitution was 10%. Flexural strength was determined by testing specimens of (100×100×500) mm, and splitting tensile strength was determined at 7 and 28 days using cylindrical specimens with dimensions (150mm × 300m).. The results obtained from these tests were compared with SIFCON containing micro steel fiber. The test results show superior characteristics of SIFCON containing hooked-end steel fiber, as compared with micro steel fiber. For example, the flexural strength and splitting strength are 24.89 MPa and 10.14 MPa, respectively for SIFCON with 8% hooked-end steel fiber and 17.51 MPa and 9.1 MPa for control specimens with micro steel fiber. [ABSTRACT FROM AUTHOR]

Self-compacting concrete (SCC) is a particular type of concrete that flows and becomes consolidated under its own weight. Various have been conducted to enhance its performance. Key developments have been the addition of fibers and replacement of the mineral admixtures; several studies have focused on varying these factors in different proportions to produce a high performance concrete. However, there is no standard mix design for self-compacting concrete containing admixtures. Therefore, optimization of the mix design is very important in order to save time and to develop an economical SCC, but there has been no detailed study of mix design and optimization of materials, and no research into the alignment and orientation of the steel fibers. Along with the uniform dispersion of fibers, few steps have been taken to optimally align the micro steel fibers, with ultrasonic pulse velocity used to justify their distribution and alignment. These factors were taken into consideration in this study. The results show that the addition of steel fibers reduces the rheological properties of the concrete by 40%-55% compared to the control mix (MC1), although all the mixtures (MC1-MX4) justified the guidelines set by EFNARC (European Federation of National Association Representing for Concrete). All the specimens failed under shear. The addition of hooked-end micro steel increased the flexural strength compared to the control mixture and a 60% increase in MX4 and 75% increase in MA7 were observed compared to MC1. The fibers were aligned along the direction of flow and the alignment properties was justified by flexural strength and UPV. A regression equation was finally developed between flexural strength and UPV for future development, which predicts the behavior of micro steel fiber reinforced self-compacting concrete (MSFRSCC).

This research study presents the mechanical behaviour of new hybrid fiber reinforced engineered cementitious composite. Uniaxial compressive, four-point bending, direct tensile test, non-destructive testing and scanning electron microscopy of materials were performed to characterize the behaviour of new hybrid reinforced ECC. The replacement of polyvinyl alcohol (PVA) fiber with polyester (PET) fiber showed that the increment of PET fiber percentage in cement matrix enhanced the tensile strain and mid-point deflection; whereas, decreased the strength properties. Amalgam of three type of fibers at percentage level 1, 0.5 and 0.5 respectively in cementitious material increased the strength parameters; while, tensile strain and deflection decreased. Recorded ultrasonic pulse velocity values exhibited that the combined dispersion of polymeric and non-polymeric fibers do not affect the quality of concrete. Mechanical behaviour of different ECC matrices demonstrated that the dispersion of low modulus fiber enhanced the mid span deflection and tensile strain capacity; however, the inclusion of high modulus fiber improved the ability of matrix to sustain higher loadings. Hybridization of fibers cut the total cost of the cementitious matrix which promotes the use of ECC at large scale. [ABSTRACT FROM AUTHOR]

In recent years, a new type of fiber reinforced concrete (FRC), called hybrid FRC, comprised of fibers of the same material but with different geometry has been developed. The aim of this paper is to investigate the influence of volume fraction and aspect ratio of steel fibers on the basic engineering properties of hybrid steel fiber reinforced concrete. To this end, steel fiber reinforced concrete composites, comprised of different combinations of fiber volume fraction and fiber size/shape, are experimentally tested and compared in terms of compressive, splitting tensile strengths and flexural toughness by four-point bending tests. The results indicate that both micro and macro size steel fibers generally improve various engineering properties of concrete, despite advantages of one on the other for different mechanical properties. Straightforward relations are proposed relating the significant mechanical properties of hybrid steel FRC to the volume fraction of micro and macro steel fibers in the composite.

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Steel fiber reinforced cementitious composites (SFRCC) have emerged as one of the most efficient techniques to improve the flexural capacity and ductility performance of concrete. However, one of the most significant shortcomings is the randomness of steel fibers direction in the concrete matrix, which influences the extent of mechanical enhancement for a limited fiber content. An experimental approach to control the direction of steel fibers embedded in self-compacting concrete is presented in this study, which is based on generating a driving rotating force to overcome the viscous impeding forces acting onto the embedded fiber. The mechanical performance of micro steel fiber reinforced self-compacting concrete members was investigated. A uniform magnetic field of 9.8 × 10−3 Tesla generated by a cylindrical powered coil was capable of aligning micro steel fibers embedded in fresh self-compacting concrete along the desired direction. The testing program included seven beam specimens of size of 100 × 100×500 mm3. The micro steel fiber contents considered were 0.35%, 0.70%, and 1.05% by volume. Fiber volume fraction of 0.35% was the optimum dosage for magnetic alignment as it achieved the highest extents of mechanical enhancement. The concrete specimens reinforced with 0.35% of steel fiber content have exhibited enhancement rates of 5%, 28%, and 30% in four-point failure load, maximum mid-span deflection, and compressive strength, respectively. Based on the visual analysis of cross-sectional images, the highest orientation factor achieved was 0.91 when steel fiber dosage was 0.35%, whereas the random non-magnetized steel fiber reinforced beams achieved an orientation factor ranging from 0.30 to 0.50. • A detailed approach of aligning steel fibers magnetically in concrete was presented. • Self-compacting concrete of low viscosity promoted a greater efficiency of alignment. • Magnetic alignment of embedded steel fibers improved the mechanical characteristics. • The impact of using different micro steel fiber contents was elucidated. • Detection of orientation factor confirmed the efficiency of magnetic alignment. [ABSTRACT FROM AUTHOR]

Ultra‐high performance fiber‐reinforced concrete (UHPFRC) is usually applied for thin‐walled and lean constructions because of its excellent mechanical properties. However, these lightweight constructions such as bridge girders, masts, towers, and railway tracks, for example, are susceptible to oscillations due to cyclic loading. A model describing the fatigue behavior of UHPFRC is required. Therefore, the material behavior of all mixture components and the composite itself, each subjected to cyclic tensile loading, is studied experimentally and numerically on the mesoscale at iBMB, Division of Concrete Construction and Institute of Structural Analysis both at TU Braunschweig. In this paper, first findings concerning bond processes of single and multiple micro steel fibers embedded in ultra‐high performance concrete as well as a new geometrically and physically nonlinear bond model are presented. [ABSTRACT FROM AUTHOR]

Self-compacting concrete (SCC) is a particular type of concrete that flows and becomes consolidated under its own weight. Various have been conducted to enhance its performance. Key developments have been the addition of fibers and replacement of the mineral admixtures; several studies have focused on varying these factors in different proportions to produce a high performance concrete. However, there is no standard mix design for self-compacting concrete containing admixtures. Therefore, optimization of the mix design is very important in order to save time and to develop an economical SCC, but there has been no detailed study of mix design and optimization of materials, and no research into the alignment and orientation of the steel fibers. Along with the uniform dispersion of fibers, few steps have been taken to optimally align the micro steel fibers, with ultrasonic pulse velocity used to justify their distribution and alignment. These factors were taken into consideration in this study. The results show that the addition of steel fibers reduces the rheological properties of the concrete by 40%-55% compared to the control mix (MC1), although all the mixtures (MC1-MX4) justified the guidelines set by EFNARC (European Federation of National Association Representing for Concrete). All the specimens failed under shear. The addition of hooked-end micro steel increased the flexural strength compared to the control mixture and a 60% increase in MX4 and 75% increase in MA7 were observed compared to MC1. The fibers were aligned along the direction of flow and the alignment properties was justified by flexural strength and UPV. A regression equation was finally developed between flexural strength and UPV for future development, which predicts the behavior of micro steel fiber reinforced self-compacting concrete (MSFRSCC). [ABSTRACT FROM AUTHOR]

• FA with EPP were considered as a sustainable replacement material to produce geopolymer mortar. • Flexural and deflection behaviours of FRGM varied depending on the fiber types. • FRGM specimens had a significant reduction in residual compressive strength, especially at 600 °C. • The use of MS fibers in geopolymer mortar could overcome its brittleness to certain extent. This study aims to explore the potential of ambient-cured geopolymer as a substitute for ordinary Portland cement (OPC)-based mortar. However, due to their brittle nature, geopolymer materials require reinforcement to enhance ductility. To address this, an experimental program was conducted to investigate the effects of adding polypropylene (PP) and micro steel (MS) fibers to fiber-reinforced geopolymer mortar (FRGM) at volume fractions of 0%, 0.5%, 1%, and 1.5%. The ternary blended geopolymer mortar consisting of fly ash (FA), and ground granular blast furnace slag (GGBS), along with a novel pozzolan called eco-processed pozzolan (EPP) was investigated. The present study assessed the hardened properties of the FRGM, including compressive strength, splitting tensile strength, modulus of elasticity (MoE), ultrasonic pulse velocity (UPV), and the compressive strength of the material when exposed to elevated temperatures. The aim of this study was also to investigate the load–deflection response in terms of deflection, load, flexural strength, and toughening mechanisms; and also, the bonding between the fibers and the mortar matrix was examined using field emission scanning electron microscopy (FESEM). The results indicated that including 0.5% PP fibers and up to 1.5% MS fibers marginally improved compressive strength and MoE. The corresponding increments in splitting tensile strengths were 5% and 134%, respectively. The addition of fibers improved the fracture parameters of the FRGM. The inclusion of both MS and PP fibers significantly enhanced post-cracking flexural and toughness energy. At deflection L/150, MS fiber mixes exhibited 4–5 times higher toughness energy than PP fiber mixes, and also its evidently observed in the FESEM micrographs. The incorporation of 1.5% fiber volume to non-fibrous mix resulted in an improvement of 43.2 N.m. and 10.1 N.m. in toughness (T 150) for MS and PP mixes, respectively. At an elevated temperature of 600 °C, the FRGM specimens gained a massive reduction in compressive strength, with the maximum result being at 87% for 1.5PP and 71% for 0.5MS. Overall, the MS fiber-reinforced geopolymer mixes exhibited superior performance as compared to PP fibers. [ABSTRACT FROM AUTHOR]

The construction of highly safe and durable buildings that can bear accident damage risks including fire, earthquake, impact, and more, can be considered to be the most important goal in civil engineering technology. An experimental investigation was prepared to study the influence of adding various percentages 0%, 1.0%, and 1.5% of micro steel fiber volume fraction (Vf) to reactive powder concrete (RPC)—whose properties are compressive strength, splitting tensile strength, flexural strength, and absorbed energy—after the exposure to fire flame of various burning temperatures 300, 400, and 500 °C using gradual-, foam-, and sudden-cooling methods. The outcomes of this research proved that the maximum reduction in mechanical properties is detected in case of 0% addition at burning temperature of 500 °C using sudden cooling to be 63.90%, 55.77% and 53.8% for compressive, splitting tensile, and flexural strength, respectively, while using 1.5% produced a modification in compressive strength, splitting tensile strength, and flexural strength to 6.67%, 4.15%, and 7.00% respectively, and 7.10 kN·mm for the absorbed energy for gradual cooling at 300 °C. From the results, the adopted cooling methods can be ordered according to their negative influence by sudden, foam, and gradual, while the optimum percentage of (Vf) is 1.5% when burning at 300 °C for all methods of cooling. 1.0% is considered the optimum percentage for all burning temperatures that exceed 400 °C using sudden-cooling method.

Self compacting mortars (SCMs) plate specimens with dimension of (500×500×40) mm were cast with three-dimension (3D) textile glass fiber having three diverse thicknesses 6, 10, and 15mm to measure their punching strength. Plates with one and two layers of chicken wires, as well as micro steel fiber of 0.75 % volume fraction were tested under punching for comparison. Punching shear tests have been carried out by applying concentrated load with steel cylinder of 50mm diameter and 10 mm height. The mechanical behavior of SCMs plate was discussed in terms of observed behavior, ultimate load, load - deflection curves, and crack pattern. The results indicated an enhancement in the ultimate load at (28 and 90) day ages by about (7.82% and 24%), respectively. The maximum ultimate load was increased by about (58.4 and 54.1) % for plates reinforced by micro steel fiber at 28 and 90 days, respectively as compared with reference. The maximum deflection at the center of the Self-compact mortars plates for all tested plates was improved. [ABSTRACT FROM AUTHOR]

In the construction of concrete slabs using steel deck plates, top reinforcing bars are required at the interior supports to resist the negative moment or to restrain flexural cracking. However, such reinforcing bar work degrades constructibility and economy. In the present study, the use of steel fiber-reinforced concrete (SFRC) was studied to remove the need for on-site reinforcing bar work. To verify the effect of the steel-fiber reinforcement on crack control, flexural tests were performed for two-span composite and non-composite slabs. The major test parameters were the use of steel fiber, the types of steel deck plate, and the use of top bars. The test results showed that in the slab specimens with steel deck plates and steel fibers, the flexural stiffness and load-carrying capacities were significantly greater than those of the counterpart conventional reinforced concrete (RC) slab. Due to the high stiffness and strength of the slabs with steel deck plates and steel fibers, even without top bars, flexural cracking was successfully restrained under service loading. [ABSTRACT FROM AUTHOR]

Self compacting mortars (SCMs) plate specimens with dimension of (500×500×40) mm were cast with three-dimension (3D) textile glass fiber having three diverse thicknesses 6, 10, and 15mm to measure their punching strength. Plates with one and two layers of chicken wires, as well as micro steel fiber of 0.75 % volume fraction were tested under punching for comparison. Punching shear tests have been carried out by applying concentrated load with steel cylinder of 50mm diameter and 10 mm height. The mechanical behavior of SCMs plate was discussed in terms of observed behavior, ultimate load, load - deflection curves, and crack pattern. The results indicated an enhancement in the ultimate load at (28 and 90) day ages by about (7.82% and 24%), respectively. The maximum ultimate load was increased by about (58.4 and 54.1) % for plates reinforced by micro steel fiber at 28 and 90 days, respectively as compared with reference. The maximum deflection at the center of the Self-compact mortars plates for all tested plates was improved.

Abstract: This study investigated the mechanical properties of ultra high performance fiber reinforced cementitious composites (UHPFRCC) with four different fiber volume fractions (Vf =1%, 2%, 3%, and 4%) within an identical mortar matrix. The higher amount of fiber resulted in an improvement of load carrying capacity and elastic modulus in compression up to 3vol.% of fibers. A higher pullout strength was obtained from the inclusion of fibers in the matrix, and 2vol.% of fibers provided the best performance in all aspects of fiber pullout behavior including average and equivalent bond strengths and pullout energy. The flexural strength was pseudo-linearly increased with increase in fiber volume fraction, despite an insignificant difference in the first cracking load. Furthermore, a bi-linear softening curve for UHPFRCC was suggested based on the result of inverse analysis, and it was verified through comparison with the experimental data. [Copyright &y& Elsevier]

The construction of highly safe and durable buildings that can bear accident damage risks including fire, earthquake, impact, and more, can be considered to be the most important goal in civil engineering technology. An experimental investigation was prepared to study the influence of adding various percentages 0%, 1.0%, and 1.5% of micro steel fiber volume fraction (Vf) to reactive powder concrete (RPC)—whose properties are compressive strength, splitting tensile strength, flexural strength, and absorbed energy—after the exposure to fire flame of various burning temperatures 300, 400, and 500 °C using gradual-, foam-, and sudden-cooling methods. The outcomes of this research proved that the maximum reduction in mechanical properties is detected in case of 0% addition at burning temperature of 500 °C using sudden cooling to be 63.90%, 55.77% and 53.8% for compressive, splitting tensile, and flexural strength, respectively, while using 1.5% produced a modification in compressive strength, splitting tensile strength, and flexural strength to 6.67%, 4.15%, and 7.00% respectively, and 7.10 kN·mm for the absorbed energy for gradual cooling at 300 °C. From the results, the adopted cooling methods can be ordered according to their negative influence by sudden, foam, and gradual, while the optimum percentage of (Vf) is 1.5% when burning at 300 °C for all methods of cooling. 1.0% is considered the optimum percentage for all burning temperatures that exceed 400 °C using sudden-cooling method. [ABSTRACT FROM AUTHOR]