Effect Of Reinforcement Research Articles

Analysis of reinforcement effect of different anchoring forces on slope stabilised by prefabricated anchorage cable frame beams

Prefabricated anchorage cable frame beams represent a new approach to slope reinforcement, displaying distinct deformation and stress patterns under varying anchoring forces compared to traditional cast-in-place frame beams. This renders the traditional theories and engineering practices of cast-in-place beams inapplicable. Field tests and sophisticated finite-difference simulation models were established to examine the mechanical performance of prefabricated beams under different anchoring forces. Initially, field test results validated the simulation models against measured and theoretical data. Subsequently, the impact of different anchoring forces on slope deformation, structural deformation, and stress in frame beams were explored. The beam pressure at the anchoring point of prefabricated beams was 24 % lower than that of cast-in-place beams, exhibiting a linear relationship with increasing anchoring forces and heightened initial sensitivity. Prefabricated beams showed a 20–30 % reduction in anchoring force loss over traditional beams when the anchoring force is not greater than 40 t. Notably, tensile stress emerges in prestressed prefabricated beams when anchoring forces exceed 50 t. The slope deformation with the increasing of anchoring force can be described by a power function. A new deflection deformation index for frame beams was proposed, showing a 70 % reduction compared to cast-in-place beams. During sliding face degradation, deformation differences between adjacent prefabricated beams weaken the reinforcement effect compared to continuous cast-in-place beams. However, applying sufficient anchoring forces significantly mitigates this effect. A well-calibrated anchoring force ensures superior performance of prefabricated anchorage cable frame beams, with enhanced crack resistance, reduced anchoring force loss, minimal deflection deformation. Moreover, the prefabricated beam structure is easy for local replacement and maintenance. This study can make a reference for the application and design of prefabricated structures for slope stabilisation.

Numerical Modeling of Distributed Macro-Synthetic Fiber and Deformed Bar Reinforcement to Resist Shear

Macro-synthetic fibers are increasingly used in concrete as secondary reinforcement to control temperature and shrinkage cracks, improving durability by limiting crack widths. However, their impact on the shear strength of structural elements remains underexplored, particularly when used in combination with traditional steel reinforcement. To address this knowledge gap, this study developed and calibrated a non-linear numerical model to simulate the shear response of macro-synthetic fiber-reinforced concrete (PFRC) elements, using finite element software VecTor2. The model was calibrated with experimental data from PFRC panels subjected to pure shear loading, incorporating a custom concrete tension-softening model to capture the contribution of fibers. Validation against a broad range of PFRC beam experiments from the literature demonstrated the model’s accuracy, achieving an average predicted-to-experimental shear strength ratio of 0.99 (COV = 5.5%). Additionally, the model successfully replicated key response characteristics such as deformation patterns, crack propagation, and residual strength. The proposed modeling approach provides valuable insights into the interaction between fiber volume and transverse reinforcement. It also serves as a powerful tool for future numerical studies, addressing the existing data gap on PFRC behavior and exploring the synergistic effects of macro-synthetic fibers and steel reinforcement on shear strength.

Influence of web reinforcement on shear behavior and size effect of lightweight aggregate concrete deep beams: Experimental and theoretical studies

In practice, deep beams with web reinforcement are the predominant form of deep beams. Understanding the effect of web reinforcement in deep beams made of lightweight aggregate concrete (LWAC) is essential for the structural application of LWAC deep beams, but it is still a pending subject. In this study, eight LWAC deep beams and two normal weight concrete deep beams were tested to investigate the influence of web reinforcement and beam depth on the shear behavior and size effect of LWAC deep beams. The experimental results showed that all deep beams failed in shear–compression mode, which is independent of the web reinforcement ratio and beam depth. The web reinforcement confined the concrete within the strut area and limited the concrete spalling, which positively affected the normalized serviceability/ultimate shear strength. Moreover, web reinforcement effectively mitigated the size effect by resisting the transverse tensile stress and improving the boundary confinement of the concrete struts, but could not eliminate the size effect in LWAC deep beams. Based on these results, a modified strut-and-tie model (MSTM) was developed to quantify the contribution of web reinforcements to the shear capacity more accurately than the conventional strut-and-tie model. The predictions obtained using the MSTM with the Warwick-Foster’s strut efficiency factor were in excellent agreement with the experimental results.

PLA based biodegradable bionanocomposite filaments reinforced with nanocellulose: development and analysis of properties

The 3D printing technique has recently become more prevalent among researchers for the fabrication of nanocomposites. The low crystallinity of polylactic acid (PLA) leads to the poor mechanical and thermal properties of its 3D-printed products, which restrict their applications in many fields. To overcome the limitations of PLA, the present work aims to develop PLA-based bionanocomposite filaments with varying percentages (1, 3, and 5 wt%) of crystalline nanocellulose (CNC) through a single screw extruder. The filaments will be further utilized for the development of bionanocomposite samples to evaluate their properties. The effect of CNC reinforcement on the chemical structure of the filaments was analyzed by FTIR analysis. XRD analysis revealed that the crystallinity of the filaments was significantly improved due to the nucleating effect of CNC. The maximum crystallinity was observed in the filament containing 1 wt% CNC, which was 26% higher than the pure PLA filament. The thermal and mechanical performance of the filaments was also considerably improved after CNC reinforcement, which was confirmed by DSC-TGA and tensile test analysis. The maximum tensile strength and tensile modulus were observed to be 48.9 MPa and 1700 MPa, respectively, in the filament reinforced with 1 wt% CNC, which was 35.5% and 21.89%, respectively, higher than those of the pure PLA filament. Rheological analysis showed that the complex viscosity, storage modulus, and loss modulus of the filaments were significantly affected by the reinforcement of CNC.

Remembering as an operant: Effects of instructional control and reinforcement on remembering behavior.

With the general aim of providing more evidence for considering certain behaviors involved in the act of remembering as operant, two experiments were carried out to verify its sensitivity to differential reinforcement, and to some of the variables upon which it depends. In the first experiment, three children participated, and two variables were manipulated in a "free recall" task: the accuracy of the instructions and the magnitude of the reinforcer applied to the emission of the target words. In the second experiment, 60 was changed to one of comparison between groups. In this case, the response-reinforcer interval (immediate vs. delayed) was manipulated using a "recognition" task. In both experiments, a greater number of remembered items were found in the presence of reinforcement compared to its absence, as well as with a greater magnitude of the reinforcer and with a shorter delay. These results are discussed considering the peculiarities of verbal behavior in humans and provide evidence that operant processes have an important role in traditional human memory tasks.

Reinforcement effects of graphene oxide in polyamide 6 nanocomposite system synthesized by in-situ polymerization

In this study, the excellent enhancement in the mechanical properties and thermal properties of polyamide 6 (PA6) by the incorporation of very low content of graphene oxide (GO) was achieved. For example, the Young's modulus of PA6/GO nanocomposites with 0.5 wt% GO was 138 % higher than that of PA6. In addition, the thermal decomposition temperature increased from 341 °C of PA6 to 361 °C by the addition of only 0.5 wt% of GO. The detailed effect of GO on the structure (e.g. dispersibility, orientation, alignment, crystallinity, interfacial interactions) of the nanocomposites were investigated. Understanding the reinforcing effect of GO and its mechanism is important for the designing of polymer nanocomposites which can provide strong candidates for light weight and smart applications in various fields.

The Effect of Tertiary Ceramic Particle Reinforcement on the Mechanical Characteristics of Hybrid Composites Based on Al7029

The Effect of Tertiary Ceramic Particle Reinforcement on the Mechanical Characteristics of Hybrid Composites Based on Al7029

Biodiversity and Soil Reinforcement Effect of Vegetation Buffer Zones: A Case Study of the Tongnan Section of the Fujiang River Basin

The riparian vegetation buffer zone is an important component of riverbank ecosystems, playing a crucial role in soil consolidation and slope protection. In this study, the riparian vegetation buffer zones in the Tongnan section of the Fujiang River Basin were selected as the research object. Surveys and experiments were conducted to assess the species composition and the soil and water conservation effectiveness of the riparian vegetation buffer zone. There are a total of 35 species, mainly comprising angiosperms and ferns. The dominant species include Cynodon dactylon, Setaria viridis, Phragmites australis, Erigeron canadensis, and Melilotus officinalis. The Patrick richness index (R) and Shannon–Wiener diversity index (H) are more significantly influenced by the types of land use in the surrounding area, whereas the impact on the Simpson diversity index (D) and Pielou uniformity index (E) is comparatively less pronounced. When the root diameter is less than 0.2 mm, the tensile strength of Cynodon dactylon roots is the highest. For root diameters larger than 0.2 mm, Melilotus officinalis roots exhibit the highest tensile strength. The presence of plant root systems significantly reduces erosion, delaying the time to reach maximum erosion depth by 1–4 min, decreasing erosion depth by 9–38 mm, and reducing the total amount of erosion by 20.17–58.90%. The anti-scouribility effect of Cynodon dactylon is significantly better than that of Setaria viridis. The root system notably enhances soil shear strength, delaying the shear peak by 0.26–4.8 cm, increasing the shear peak by 4.76–11.37 kPa, and raising energy consumption by 23.76–46.11%. Phragmites australis has the best resistance to shear, followed by Erigeron canadensis, with Melilotus officinalis being the least resistant. Therefore, to balance the anti-scouribility effect and shear resistance of plant roots, it is recommended to use a combination of Cynodon dactylon and Phragmites australis for shallow-rooted and deep-rooted planting. This approach enhances the water and soil conservation capacity of riverbanks.

Carbon fiber/nano SiO2 reinforced polyelectrolyte-graft UHMWPE for water lubricated superlubricity

In this study, a new kind of UHMWPE composite with ultralow coefficient of friction (COF) and high mechanical properties was developed. An efficient method was established to graft hydrophilic monomer 3-sulfopropyl methacrylate potassium salt (SPMK) onto UHMWPE powder by thermal initiation radical polymerization. The COF of UHMWPE grafted SPMK sample was significantly reduced by 50 %. After filling carbon fiber and nano SiO2, the COF of UHMWPE composites can be reduced as low as 0.009 at 0.1 m/s. Besides, a 76.1 % decrease in wear rate of single UHMWPE was achieved. The outstanding tribological properties of UHMWPE composite was attributed to the synergistic effect of hydration lubrication and particle reinforcement. The prepared UHMWPE composite has great potential to realize water lubricated bearing.

The effect of compression reinforcement on the shear behavior of concrete beams with hybrid reinforcement

The effect of compression reinforcement on the shear behavior of concrete beams with hybrid reinforcement

Analytical solution for radial consolidation of combined electroosmosis-vacuum-surcharge preloading considering free strain and cyclic loading

In this study, electro-osmotic consolidation considering smear effect and free strain under cyclic loading was investigated. The analytical solution of radial consolidation of electroosmosis-vacuum-surcharge combined preloading is derived by using the Bessel function and eigenfunction methods. Subsequently, the effectiveness of the proposed method is validated through comparison with existing numerical solutions. Based on the derived solutions, the influence of the smear effect, applied voltage, vacuum pressure, and cyclic loading on soil consolidation characteristics was analyzed. The results showed that the smearing effect slows the rate of consolidation, but the final average consolidation and negative excess pore water pressure are enhanced. Compared with only cyclic loading, the combined effect of electroosmosis, vacuum, and surcharge preloading enables the soil to achieve higher strength and consolidation. When the effect of electroosmosis alone on reinforcing low-permeability soils is not significant, the combination of electroosmosis with vacuum preloading helps enhance the soil reinforcement effect.

Experimental and simulation study on seismic performance of seawater sea-sand PVA cementitious composite columns with GFRP bars

The seismic properties of seven seawater sea-sand (SWSS) PVA cementitious composite columns with Glass Fiber Reinforced Polymer (GFRP) bars were studied. The effects of four parameters, namely polyvinyl alcohol (PVA) fiber content, axial compression ratio, cementitious composite strength and stirrup spacing, on the seismic performance of composite columns were analyzed. The failure of the specimen was observed, and the hysteresis curve, skeleton curve, stiffness degradation, energy dissipation capacity, ductility and strain of the specimen were analyzed. The test results show that the large chip-based spalling will occur when the specimen without fiber incorporation is damaged, and the incorporation of PVA fiber, the reduction of stirrup spacing and the reduction of axial compression ratio will delay the rate of crack formation and development. In addition, through cross-section analysis and considering the reinforcement effect of PVA fibers, a proposed formula for calculating the horizontal bearing capacity of composite columns is proposed. Finally, the finite element model of SWSS PVA cementitious composite columns with GFRP bars is established, and it is found that increasing the strength grade of cementitious materials can greatly improve the seismic performance of composite columns. The conclusions could be references for the engineering application. In the context of the global emphasis on green development and environmental protection, seawater and sea-sand cementitious composites and components with fiber reinforcement will have a wide range of application prospects in the construction of coastal areas.

Study on increasing load capacity of wooden arch bridge by CFRP strengthening: experimental and numerical Verification

The wooden arch corridor bridge is a typical representative of Chinese wooden bridges, holding significant historical research value. Currently, these bridges face issues of severe component deformation and insufficient load-bearing capacity. To address these problems, this study employs CFRP reinforcement on the components of wooden arch corridor bridges to reduce deformation and enhance load-bearing capacity. Experimental research on CFRP reinforcement has yielded the elastic modulus of the bonding interface. Given the lack of an accurate numerical model for wooden arch corridor bridges, this study establishes a precise numerical model by setting parameters based on load test data from wooden arch corridor bridges. The elastic modulus obtained from the experiments is input into the numerical model for analysis. The results indicate that CFRP exhibits excellent reinforcement performance, with the load-bearing capacity of the reinforced damaged components still reaching 75%–85% of their original capacity, while the load-bearing capacity of the reinforced undamaged components increases to 130%–140% of their original capacity. The failure modes of the CFRP-reinforced wooden components suggest that allowing for some gaps in the bonding of CFRP can enhance overall ductility. The application of CFRP to wooden arch corridor bridges also demonstrates favorable reinforcement effects, increasing the load-bearing capacity of the arch surface by approximately 20%, thereby providing a theoretical basis for the reinforcement of wooden arch bridge frameworks.

Effect of Fibre Reinforcement on Compressive Strength and Compressive Modulus of Epoxy Granite

Abstract The main focus of the paper is to study the effect of fibre reinforcement on compressive strength and compressive modulus of epoxy granite. To investigate the effect of fibre reinforcement, two compositions were considered likes 20% Epoxy and 80% Granite without fibre reinforcement and 20% Epoxy, 75% Granite and 5% fibre reinforcement. Based on the literature studied, three types of fibre were considered viz. steel fibre, carbon fibre and basalt fibre. Three specimens of each type of fibre i.e. nine specimens and three specimens without fibre reinforcement were prepared. The obtained maximum compressive strength and compressive modulus of epoxy granite without reinforcement is 91.70 MPa and 3.5 GPa for the composition of 20% epoxy and 80% granite. The observed maximum compressive strength of 78.57 MPa for 20% epoxy and 75% granite with 5% carbon fibre reinforcement epoxy granite (CFEG) which is much higher than steel fibre reinforced epoxy granite (SFEG) with 20% epoxy and 75% granite and basalt fibre reinforced epoxy granite (BFEG) with 20% epoxy and 75% granite. The computed compressive modulus is 2.7 GPa for SFEG with 5% fibre which greater than CFEG and BFEG with the same fibre content.

A time-varying non-probabilistic reliability analysis method using surrogate model for the reinforcement effectiveness of damaged concrete gravity dam

Evaluation of the effectiveness of reinforcement measures for the diseased concrete gravity dam is a critical issue in the field of hydraulic structural health control. The traditional probabilistic reliability analysis method is constrained by factors such as the randomness of the uncertain parameters, the high nonlinearity of the performance function, etc., when it is applied to the evaluation of the effectiveness evolution of reinforcement measures for the diseased concrete gravity dam. Therefore, a time-varying non-probabilistic reliability (NR) analysis method is proposed in the research. To characterize the uncertainty of the parameters, we adopt the form of interval numbers to present parameters and construct the interval parameter-based reliability analysis framework. Specifically, combining interval mathematics and non-probabilistic reliability theory, the NR calculation model for the gravity dam is proposed. In addition, considering of the aging of the structure, the time-varying NR (TV-NR) calculation model utilized to evaluate the long-term reinforcement effectiveness is established. To tackle the issue of expensive computation existed in the TV-NR model, response surface method (RSM) is coupled in the TV-NR calculation model to replace the original high nonlinearity performance function. Ultimately, the proposed method is verified in engineering examples that it can detect the most possible initial locations and failure processes of the gravity dam varying with time and can efficiently and accurately evaluate the reinforcement effectiveness of the gravity dams. The results indicate that the use of reinforcement measures can provide an improvement for the safety service of gravity dams.

Flexible and Flame Retardant Cotton Fiber-reinforced CS/CNF/EP Composites For a Sensitive Fire Warning

Enhancing fire safety performance in resin-based composites is critical for mitigating fire hazards. Composites that provide early warnings during initial fire stages and maintain prolonged alarm capabilities under flame exposure are essential for minimizing injuries and property damage. This study employs chitosan (CS) as a cross-linking and char-forming agent, while carbon nanofiber (CNF) acts as a flame retardant and conductive component. Cotton fiber-reinforced chitosan/carbon nanofiber composites with varying epoxy and CNF contents (CS/CNF/EP) were prepared through a straightforward low-temperature curing process (40 °C, 4 h). Crosslinking polymerization between chitosan and epoxy was confirmed via Fourier Transform Infrared Spectroscopy (FTIR). The presence of the tough structure of CS and the rigid structure of EP results in a synergistic toughening and reinforcement effect in the CS/CNF/EP composites. Additionally, due to the carbon facilitating properties of CS and the enhanced conductivity of CNF, the composites exhibit a sensitive fire alarm functionality. At 35 % epoxy content, the CS/CNF/EP composites demonstrated exceptional properties, including mechanical flexibility (tensile strength of 7.09 MPa and breaking elongation of 129.05 %) and outstanding flame retardancy (LOI of 32.3 % and UL-94 V-0 rating). These composites provided a rapid alarm (∼1 s), sustaining a 263 s warning under flame exposure and over 35 min post-flame removal. These findings indicate that CS/CNF/EP composites, integrating mechanical flexibility, flame retardancy, and superior fire warning properties, present significant potential applications in fire safety engineering.

Effect of nanoparticles reinforcement of silicon dioxide derived from prosopis juliflora on Silver-Grey magnesium nanocomposite: utilization of silicon dioxide mechanical and tribological properties

Abstract The automotive and aviation industries require lightweight materials to enhance working efficiency. Composites combine materials such as aluminium, magnesium, titanium, steel, and copper with various forms of reinforcements to offer lightweight alternatives for a range of applications. The present investigation aims to fabricate a Silver-Grey Magnesium (Mg-25%Si) alloy-based nanocomposite with silicon dioxide (SiO2) nano reinforcement at weight % of 0, 3.25, 6.5 and 9.75 utilizing the two step stir casting method. Prosopis juliflora is utilized in the production of different weight percentages of SiO2 nano reinforcements. The microhardness, tensile, wear, and impact tests are performed on the Silver-Grey Magnesium nanocomposites (Mg-25%Si/SiO2) utilizing a computerized tensometer testing machine, a Vicker’s hardness tester, a pin-on-disc tribometer, and an Izod impact, respectively. The x-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), and Energy-dispersive x-ray spectroscopy (EDAX) with elemental mapping microstructure were employed to scrutinize the tensile specimen fracture, EDAX, elemental mapping microstructure, wear, CoF, and worn surface characterization and impact strength analysis. When compared to the Silver-Grey Magnesium (Mg-25%Si) base alloy, the results of the Mg-25%Si/SiO2 nanocomposites demonstrated an increase in SiO2 nano reinforcements that significantly increased microhardness, tensile strength, wear resistance, and impact strength. The corresponding values are 113.36 VHN, yield and ultimate tensile strength of 603.25 MPa and 665.84 MPa, 0.00478 mm3 m−1, CoF of 0.38421 and 400 J m−1.

Strengthening of mechanical and tribological properties in CrFeCuMnNi high entropy alloy through dispersion of TiO2 reinforcement via powder metallurgy processes

The present study reports the effect of TiO2 reinforcement on the phase, microstructure, mechanical and tribological properties of CrFeCuMnNi/TiO2 high entropy alloy composites (HEACs) processed by powder metallurgy. The results reveal the formation of single-phase face-centered cubic (FCC) structure after 30 h of milling in the original HEA, while TiO2 peaks in the HEACs indicate uniform distribution. After sintering, multiple phases including FCC, Cr-rich, Cr2O3 were observed. The hardness of HEAs increased from 330±10 to 440±10 HV and compressive yield strength increased from 480 to 760 MPa while scarifying the strain from 43.5 to 21 % with TiO2 content. The addition of TiO2 content slightly reduces the coefficient of friction and specific wear rate decreased by 45.16 % due to increased hardness and formation of stable oxide layer on the worn surface inhibits plastic deformation. The addition of TiO2 reduces the dominance of abrasive and adhesive wear and enhances the strength of HEACs.

Enhancing sapphire/Kovar alloy brazed joint through combined effect of TiB whisker reinforcement and surface micro-nano structures

The brazed joining between Kovar alloy and sapphire was successfully achieved by using TiB whisker reinforcement and applying the surface micro-nano structure. We systematically studied the composition and mechanical properties of Kovar/Sapphire joint. The typical interfacial structure of the joint brazed at 825 °C for 10 min was determined as Sapphire/ γ-TiO/ Ti3(Cu,Al)3O/ Ag(s,s) + Cu(s,s) + TiB/ Ti2Cu + TiFe2 + TiNi3/ Kovar alloy. The addition of B forms tiny TiB whisker reinforcement phase in situ, which refines the interface structure. The presence of micro-nano structures improves the interface products on the sapphire side: reducing the generation of Ti3(Cu,Al)3O and replacing it with γ-TiO. This makes the phase transition on the sapphire side smoother and reduces thermal expansion coefficient mismatch, thereby enhancing joint strength. Under suitable brazing parameters, the maximum shear strength of the joint is 137 MPa. This study provides new insights for optimizing and improving connections between sapphire ceramics and metals, with potential applications in more ceramic/metal joining.

Evaluating the effect of Incorporating Chicken Feather Fibers on the Technological Properties of Eco-Friendly Compressed Earth Bricks

This paper investigates the feasibility of improving the performance of raw bricks by using chemically treated chicken feather fibers as a sustainable reinforcement material. Although numerous studies have already explored the use of chicken feathers in brick composites, this work is distinguished by the application of a novel chemical treatment involving formaldehyde and silane to enhance the fibers' compatibility with the clay matrix. The treated fibers were incorporated into raw brick samples at varying concentrations. The effects of fiber reinforcement on critical properties such as porosity, bulk density, compressive strength, and thermal conductivity were systematically analyzed. The results indicate that incorporating chemically treated chicken feather fibers reduces porosity and bulk density while increasing compressive strength within an optimal concentration range. Additionally, a significant reduction in thermal conductivity was observed, demonstrating the potential of these materials to improve thermal insulation in construction applications. This study highlights the promise of utilizing chicken feather waste, treated with formaldehyde and silane, as reinforcement in the production of eco-friendly bricks, with implications for sustainable construction practices.