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Polymers have been heavily used in manufacturing for decades, and with their use, improvements in the desired materials via composite materials utilizing a polymer matrix have been commonplace. Naturally, the increase in polymer additive manufacturing has come with an increase in interest in additively manufacturing polymer composites. This paper primarily covers the fused deposition modeling (FDM) method, ultraviolet (UV)-cured resin methods, multiple resin printing, and embedded sensors associated with additive manufacturing. In particular, the manufacturing and subsequent effect on material properties compared to unreinforced and unmodified 3D-printed polymers, the tradeoffs required in doing so, and the mechanisms behind these effects are discussed. The manufacturing methodology used or developed and the mechanisms behind these selections are discussed along with insights that could be gathered from material property effects seen across different studies. The mechanisms discussed also focus on the mechanisms between the different materials comprising the composite produced. [ABSTRACT FROM AUTHOR]

Prior research on cascading failures within interdependent networks has predominantly emphasized the coupling of nodes. Nevertheless, in practical networks, interactions often exist not just through the nodes themselves but also via the connections (edges) linking them, a configuration referred to as edge-coupled interdependent networks. Past research has shown that introducing a certain percentage of reinforced nodes or connecting edges can prevent catastrophic network collapses. However, the effect of reinforced inter-layer links in edge-coupled interdependent networks has yet to be addressed. Here, we develop a theoretical framework for studying percolation models in edge-coupled interdependent networks by introducing a proportion of reinforced inter-layer links and deriving detailed expressions for the giant and finite components and the percolation phase transition threshold. We find that there exists a required minimum proportion of the reinforced inter-layer links to prevent abrupt network collapse, which serves as a boundary to distinguish different phase transition types of a network. We provide both analytical and numerical solutions for random and scale-free networks, demonstrating that the proposed method exhibits superior reinforcement efficiency compared to intra-layer link reinforcement strategies. Theoretical analysis, simulation results, and real network systems validate our model and indicate that introducing a specific proportion of reinforced inter-layer links can prevent abrupt system failure and enhance network robustness in edge-coupled interdependent networks. [ABSTRACT FROM AUTHOR]

Composite material using coconut fiber to produce reinforced low-density polyethylene (LDPE) composite was produced for evaluating of the effect of varying fiber sizes on the mechanical (tensile, hardness, and impact strength), water absorption, and chemical resistance properties of the developed LPDE. Sample categories were prepared by varying the fiber sizes below 2.36 mm, = 2.36 mm, and = 3.35 mm at a constant 5% volume fraction loading. The water retting process was applied in the extraction and cleaning of the coconut fiber (or coir), while the developed composite material was prepared using the Hand layup Technique (HLT). The tensile and hardness properties were tested using the Universal Testing Machine (UTM) Model BDUM-2.5KN, while the impact properties were tested using the Izod Impact testing machine Model RI-300. The analysis of the water absorptivity showed that the developed composite materials have a low water absorptivity of 2% at fiber size loading below 2.36 mm. However, at higher fiber sizes of =2.36 mm and =3.35 mm loading, the water absorptivity increases significantly to 5.8% and 7.9%, respectively. Test results showed that the composites produced with fiber sizes less than 2.36 mm fiber loading has the most optimum combination of tensile and hardness properties, of 25.20Mpa and 22.96Mpa respectively but have the least impact strengths of 229 joules as compared to other sizes. It is recommended to use the hand layup technique for the production of low density polyethylene composites and this could further be used as an additive for the production of some lightweight polymer materials such as packing tools, furniture designs for tabletop, windows, door frames, cloth pegs, stool top, since its hardness, low strength, non-structural application, and moisture resistance analysis is within the acceptable limit of application for this purpose while eliminating pollution by using the waste sachets and nylon. [ABSTRACT FROM AUTHOR]

Zinc oxide reinforced composites are a promising class of materials with a wide range of potential applications. By combining ZnO with other materials, scientists and engineers can achieve advanced functionalities that go beyond the properties of the individual components. The article offers to researchers and specialists an organized and thoughtful overview on outlining the impacts of composites, emphasis on ZnO nanoparticles reinforced composites.

Background and Aims: During endoscopic sinus surgery, anaesthetic conditions significantly impact the intraoperative surgical field and bleeding during emergence. While the endotracheal tube (ETT) has been traditionally used in sinus surgery, a reinforced laryngeal mask airway (RLMA) that produces less upper airway stimulation may result in smoother emergence. Methods: A randomised controlled trial of 72 patients undergoing elective sinus surgery was conducted, with the allocation of airway technique to either ETT with a throat pack or RLMA. The primary outcome measure was emergence time, measured by time to opening eyes on commands at the cessation of anaesthesia, and the secondary outcomes were time to removal of airway device, remifentanil use, procedure times, mean arterial pressure (MAP) and the RLMA grade of blood contamination. The continuous variables were analysed using Student’s t‑tests and discrete variables, count tables were analysed using Fisher’s exact tests. Results: There was no significant difference in the emergence time between the ETT and RLMA groups (P = 0.83). Remifentanil use was significantly higher in the ETT group than in the RLMA group (P = 0.022). The ETT group showed a significantly increased total anaesthetic time (P = 0.01). MAP was not significant during preinduction, maintenance or post‑RMLA removal. The highest grade of contamination was grade 2 in RLMA. RLMA had lower rates of postoperative adverse events. Conclusions: RLMA comparable to ETT in terms of emergence time. The RMLA group had lower remifentanil use, anaesthesia duration and fewer postoperative adverse events such as cough and throat pain. [ABSTRACT FROM AUTHOR]

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Worldwide, construction and demolition wastes contribute the most wastes. Hence, environmental concerns have been raised, and more investigations have been recommended for recycling potential. Glass and Ceramic wastes are currently disposed of in landfills. This paper aims to study the structural behaviour of non-conventional concrete made of waste glass and ceramic tiles. A comparison is conducted between the normal and non-conventional concrete beams. The nonconventional concrete is made by replacing normal sand and gravel at 25% and 50% percentages. Both glass and ceramic tiles are used separately and blended in three different types (A, B, & C) of concretes. The laboratory experiments are verified with a Finite Element model for the three reinforced concrete types using ANSYS software. The results of conducted comparison shown that the non-conventional reinforced concretes have acceptable consistent with the normal reinforced concrete, and the reuse of glass and ceramic waste is technically feasible. [ABSTRACT FROM AUTHOR]

In the domain of modern timber structural systems, timber frame constructions distinguish themselves as preferred and commonly used building methods. Their appeal arises from their architectural adaptability and their distinctive attributes, which enable rapid assembly. In this type of structural system, the effectiveness of the connections between beams and columns plays a pivotal role in determining how forces are distributed, ensuring lateral stiffness, and upholding structural safety. Various methods have been developed to ensure column-beam connections in wooden structures. Column-beam connection points deteriorate and get damaged over time. These critical areas need to be strengthened over time. In this study, glulam columns (140 mm × 140 mm) and beams(140 mm × 280 mm), which are often used as load-bearing elements in wooden structures, were used. Columns and beams are connected to each other according to the wooden notching method. Column-beam connection areas are reinforced with carbon, glass, basalt and aramid fiber reinforced polymer fabrics. After the strengthening process, bending tests of the column-beam connection samples were carried out and the load carrying capacity, total amount of energy consumed, and maximum stiffness values were determined. Additionally, FRP damages occurring in the column-beam connection areas were observed during the experiments. The optimal outcomes for encasing column-beam connections have been identified with carbon-based fiber reinforced polymers. Glassbased fiber reinforced polymers yielded the least favorable results. Aramid-based fiber-reinforced polymers demonstrated similar outcomes to those wrapped with carbon-based counterparts. Consequently, it can be deduced that reinforcing column-beam connections with FRP fabrics, be they carbon, aramid, basalt, or glass-based, can markedly enhance their strength and durability, thereby extending their operational lifespan.

Pavement distresses are among the major problems that affects to a decisive extent on the using (operational capacity) the roads and reducing their service life. Therefore, its require to limitation this distresses and knowing the reasons that lead to appearing this distresses and give the correction during the construction of roads. The major distresses is the rutting which increases at intersections and the check points when the vehicle is stopping. The reinforcement pavement layer became an important step of design and the reconstruction of pavement layers which is control of almost distress, reduce the maintenance cost, and provide long service life of roads. In this study will study using the mats of palm fronds in reinforcement pavement layers instead industrial materials due to existence the palms with large quantity in Iraq. The result display the using the mats of palms fronds reduce the rutting percent 96.7, 88.3, 83.3 at 40, 50, 60 ºC respectively at surface course according the test by wheel track machine.

This paper presents the performance of three types of small-scale shell foundations (pyramidal frustum, semi-cylindrical and prismatic shell) of the same plan area on different states of sand provided with or without reinforcement. To understand the effect of reinforcement and its dependency on the vertical embedment depth, two cases were considered, i.e. reinforcement at a depth equal to 0.5 B (B=width of foundation) and another case at a depth equal to B. Bearing capacity for different shell foundations models and settlement behaviour were studied based on the load settlement curves and compared with that of conventional flat foundation model. The experimental results show that shell models perform better than the flat foundation model in terms of bearing capacity and settlement resistance on the different states of sand with or without reinforcement. The relationship of ultimate load with the angle of internal friction was found. Reinforcement embedded at 0.5B depth was found to be better than provided at B depth in all the states of sand. It is also noticed that the bearing capacity ratio is lower for the sand reinforced at a depth of B than that of 0.5B, showing the dependency on reinforcement embedment depth. [ABSTRACT FROM AUTHOR]

Epoxy-polyamide CNTs reinforced nanocomposites have the excessive ability for their uniform structures and specific properties and have considerable attention owing to their potential applications. In this work, epoxy/polyamide (ER-PA) and CNTs reinforced epoxy/polyamide (ER-PA/CNTs) nanocomposites were prepared by using the solution casting method. Herein, Fourier transforms infrared spectroscopy (FT-IR) was applied to indicate the responsible functional groups, presented in the prepared nanocomposites. Surface morphology and particle dispersion of the prepared nanocomposites were examined by scanning electron microscopy (SEM). The obtained results demonstrated that the CNT's weight content, dispersion rates, and the surface functionalization of CNTs nanoparticles have a strong influence on the surface morphology of the prepared nanocomposites. The thermal properties and crystalline nature of the ER-PA/CNTs nanocomposites were studied by using thermogravimetric analysis (TGA) and X-ray diffraction (XRD) analyses. The prepared nanocomposites showed good thermal stability and crystalline behavior as compared to the ER-PA nanocomposites network system. From the obtained results, it can be assumed that this effort can help to design other reinforced nanocomposites for promising applications in the nanocomposites materials industry. [ABSTRACT FROM AUTHOR]

Abstract Mortar coatings have a major influence on a building’s aesthetics, valorization, and habitability, with significant effects on the mechanical behavior of masonry walls. Multiple types of meshes can be embedded in plaster to enhance both masonry and coating’s mechanical behavior, restrain crack formation, enhance the bonding between layers, and increase the wall’s seismic resistance. The reinforcement technique has simple execution and is suitable for many applications, including the strengthening of non-load bearing walls, façade performance improvement, and restoration of historical buildings. However, there is an absence of guidelines and specifications for design and execution, resulting in high variability in field applications due to the many variables involved and few in-depth studies. This paper presents a systematic review of the effects of mesh reinforcement in cementitious mortar coatings and its major applications. Mortar and mesh parameters and influences, the status of analytical and simulation models, and suggestions for future research are described.

This article aims to simulate the behavior of reinforced concrete (RC) tapered columns subjected to static loads. The experimental data used in the study are from the literature. Two of the simulated columns are slender columns tested under uniaxial eccentric loads. The third one is a short column and was tested concentrically. The concrete damaged plasticity (CDP) model offered in the Abaqus software, which accounts for stiffness degradation of concrete in both compression and tension, was used. The modulus of rupture of concrete and the value of the cracking strain proposed by the Abaqus analysis user’s manual were used as the parameters of tension stiffening. The modified Hognestadʼs model was used for the compressive behavior of concrete. The Static Riks analyses were performed with an activated geometric nonlinearity. The numerical failure load is 100.125, 99.297, and 102.16% of the experimental failure load for Models 1, 2, and 3, respectively. The agreement of the numerical results with the experimental results has confirmed the efficiency of the CDP model to simulate the concrete behavior, and has also revealed the validity of the numerical models.

The current research deals with the Reinforced Concrete (RC) beams numerical modeling using the finite element analysis software ANSYS-standard and the proposed strengthening procedure if it is urgently required to drill rectangular or circular in shape openings within their shear zones under different applied service loads levels. The shear zone is selected to investigate drilling the opening within since it is a critical zone to reduce the structural section effective area against shear. The RC beams are analyzed under two concentrated loads till failure before and after applying the proposed opening strengthening technique by means of the Carbon Fibers Reinforced Polymer sheets (CFRP). The main aim of this research is simulating the real practice situation conditions where the RC beam is subjected to the service loads, supported temporary by means of hydraulic jacks, the opening is drilled and then the strengthening is performed after which the jacking supports are released. The used finite element modeling (FEM) is verified using one of the available experimental studies of FRP-strengthened simply supported beams with and without openings which found in the literature before achieving the investigation. The results of proposed numerical nonlinear modeling are introduced. Many aspects of structural analysis such as the initial cracking loads, load deflection curves, cracking patterns and failure loads and modes for the reference (solid without opening) and un-strengthened and strengthened opening main control and services loaded RC beams are introduced and analyzed in details. CFRP opening strengthening improved the beams structural behavior as a whole. The service loads up to about 40% of the ultimate design strength relatively have an unnoticeable influence on the strengthened opening RC beams bearing capacities regardless the opening shape. Some important conclusions and recommendations for designer and executive engineers are stated.

Incorporating distiller's grains (DG) into poly(ethylene terephthalate) (PET) has not been investigated because DG is not suitable for processing at high temperatures. Hence, in this study, DG was treated with methylenediphenyl diisocyanate (MDI) to prepare reinforced DG (RDG), which was then used as a biological filler that was melt-mixed with a PET resin to produce PET/DG and PET/RDG composites. The composite mechanical properties were investigated. Compared with PET/DG composites, PET/RDG composites exhibited improved mechanical properties. When the RDG content was 12.5%, the elongation at break reached the maximum. Scanning electron microscopy was used to observe the structure of composites filled with MDI-modified DG at the tensile section, and the compatibility between RDG fillers and the PET matrix was analyzed; RDG dispersed and adhered well in the matrix. The FTIR results showed the appearance of new characteristic peaks, indicating the possibility of DG reacting with MDI after the blending with PET, as well as providing clues about the probable reaction mechanism. Through X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, and water absorption tests, the crystallinity, thermal stability, and water absorption for the composites were analyzed. The results of TGA showed that RDG had a higher thermal stability than DG. Adding DG could significantly increase the crystallinity and rate of crystallization of PET, and at the same time, it could also improve the water absorption performance of the composites. But in the case of DG modification or treatment with MDI, the water absorption was slightly reduced. The results of contact angle analysis showed that the surface of PET/RDG composites had higher hydrophobicity than that of PET/DG composites because of the tighter structure. Relative to DG, RDG also effected improvement in the thermal stability of PET. [ABSTRACT FROM AUTHOR]

Hydrogels show promise in cartilage tissue engineering (CTE) by supporting chondrocytes and maintaining their phenotype and extracellular matrix (ECM) production. Under prolonged mechanical forces, however, hydrogels can be structurally unstable, leading to cell and ECM loss. Furthermore, long periods of mechanical loading might alter the production of cartilage ECM molecules, including glycosaminoglycans (GAGs) and collagen type 2 (Col2), specifically with the negative effect of stimulating fibrocartilage, typified by collagen type 1 (Col1) secretion. Reinforcing hydrogels with 3D-printed Polycaprolactone (PCL) structures offer a solution to enhance the structural integrity and mechanical response of impregnated chondrocytes. This study aimed to assess the impact of compression duration and PCL reinforcement on the performance of chondrocytes impregnated with hydrogel. Results showed that shorter loading periods did not significantly affect cell numbers and ECM production in 3D-bioprinted hydrogels, but longer periods tended to reduce cell numbers and ECM compared to unloaded conditions. PCL reinforcement enhanced cell numbers under mechanical compression compared to unreinforced hydrogels. However, the reinforced constructs seemed to produce more fibrocartilage-like, Col1-positive ECM. These findings suggest that reinforced hydrogel constructs hold potential for in vivo cartilage regeneration and defect treatment by retaining higher cell numbers and ECM content. To further enhance hyaline cartilage ECM formation, future studies should focus on adjusting the mechanical properties of reinforced constructs and exploring mechanotransduction pathways. [ABSTRACT FROM AUTHOR]

Plant fibers are one of the most promising calcium silicate board (CSB) reinforcement materials because of their many sources, suitable sizes, high tensile strengths, and natural renewable properties. In this study, an applicable plant fiber selection method for reinforcing CSBs was established. The morphology, components, and mechanical properties of different brands of plant fibers were analyzed for factor screening. Based on the wet processes of CSBs, the effects of plant fiber additions on the mechanical properties of CSBs were studied, and the optimum addition amount of plant fiber was determined to be 8 wt.%. Through multiple linear regression analysis of the physical and chemical properties of plant fibers and the mechanical properties of CSBs, a plant fiber strengthening index (Fsi) and toughening index (Fti) of CSBs were formulated as a plant fiber applicability index. The fitted R2 values of the plant fiber strengthening index and toughening index were 0.88 and 0.71, respectively, showing good correlation. The validity of the plant fiber applicability index in evaluating the fiber reinforcement potential was verified by experiments. The results provided a significant method for the prediction of plant fibers' reinforcement potential and the selection of plant fibers for CSB reinforcement. [ABSTRACT FROM AUTHOR]

Polymer materials have been widely used in modern industries duo to their characteristics such as lightweight, low price, and corrosion resistance. However, the inherent insulation of polymer materials can cause static electricity, which has become one of the major problems that has limited their application. Meanwhile, as the basis for ensuring the service field and life of the polymer materials, mechanical properties can affect the comprehensive properties of the polymer materials. Therefore, research on the preparation of composite materials with both antistatic properties and good mechanical properties with antistatic-reinforced modification has attracted extensive attention and achieved important progress. Based on the principle of electrostatic electrification of antistatic-reinforced modification, antistatic mechanisms and main preparation strategies, this paper summarized the research achievements of the antistatic-reinforced polymer materials in recent years. Additionally, some factors that have affected their antistatic properties were presented, and the development trends of the antistatic-reinforced polymer materials based on the deficiencies of current research were proposed. [ABSTRACT FROM AUTHOR]

At present, the self-supporting paper-based electrode has some problems, such as low mechanical strength and insufficient flexibility, which restrict its application in flexible electronics. In this paper, FWF is used as the skeleton fiber, and the contact area and the number of hydrogen bonds of the fiber are increased by grinding the fiber and adding nanofibers to bridge it, and a level three gradient enhanced skeleton support network structure is constructed, which effectively improves the mechanical strength and foldability of the paper-based electrodes. The tensile strength of FWF15-BNF5 paper-based electrode is 7.4 MPa, the elongation at break is increased to 3.7%, the electrode thickness is as low as 66 μm, the electrical conductivities is 5.6 S cm−1, and the contact angle to electrolyte as low as 45°, which has excellent electrolyte wettability, flexibility, and foldability. After three-layer superimposed rolling, the discharge areal capacity reached 3.3 mAh cm−2 and 2.9 mAh cm−2 at the rate of 0.1 C and 1.5 C, respectively, which was superior to the commercial LFP electrode, it had good cycle stability, and the areal capacity was 3.0 mAh cm−2 and 2.8 mAh cm−2 after 100 cycles at the rate of 0.3 C and 1.5 C. [ABSTRACT FROM AUTHOR]

This article focuses on the effect of nano-silica on an epoxy matrix of hybrid basalt-carbon fiber reinforced polymers (FRP) composites. Usage of this type of bar continues to grow in the construction industry. The corrosion resistance, strength parameters, and easy transport to the construction site are significant parameters compared to traditional reinforcement. The research for new and more efficient solutions resulted in the intensive development of FRP composites. In this paper, scanning electron microscopy (SEM) analysis of two types of bars is proposed: hybrid fiber-reinforced polymer (HFRP) and nanohybrid fiber-reinforced polymer (NHFRP). HFRP, in which 25% of the basalt fibers were replaced with carbon fibers, is more mechanically efficient than basalt fiber reinforced polymer composite (BFRP) alone. In HFRP, epoxy resin was additionally modified with a 3% SiO2 nanosilica admixture. Adding nanosilica to the polymer matrix can raise the glass transition temperature (Tg) and thus shift the limit beyond which the strength parameters of the composite deteriorate. SEM micrographs evaluate the surface of the modified resin and fiber–matrix interface. The analysis of the previously conducted tests—shear and tensile at elevated temperatures—correlate with the microstructural SEM observations with the obtained mechanical parameters. This is a summary of the impact of nanomodification on the microstructure–macrostructure of the FRP composite. [ABSTRACT FROM AUTHOR]

In the last decades plenty of fire tests with wall constructions consisting of reinforced AAC elements were executed. Many of the test results have been transferred to European and national technical regulations. Also, theoretical methods to design reinforced AAC elements for fire impact are available. These provide temperature curves for the commonly used dry densities and procedures to calculate and rate the influence of fire stress on the functional capacity of the wall systems. In the last years additional fire tests took place to show the fulfilment of special requirements for buildings with high demands regarding fire safety. For example, tests with six hours of firing were performed which is highly above the definitions and solutions given in standards. Xella's R&D Center meanwhile has its own test stand to execute suitability checks for fire walls and is accredited for performing these tests. In the last years the question about how to rate the performance of fire walls on basis of test results came up, especially regarding load bearing walls. This is the result of different definitions in the relevant national and European standards. Possible approaches for solving this topic shall be presented at the AAC conference. [ABSTRACT FROM AUTHOR]

In the current study, we successfully prepared chitosan/gelatin composite scaffolds reinforced by centrifugally spun polylactic acid (PLA) chopped nano/microfibers (PLA-CFs). Herein, different amounts of PLA-CFs (0 %, 1 %, 2 %, 3 %, and 4 % w / v) dispersed in chitosan/gelatin solution were used. Morphological characterization of prepared scaffolds revealed that at the initial stage of adding PLA-CFs, the chopped fibers were localized at the wall of the pores; however, as the fiber load increased, aggregations of chopped-fibers could be seen. Also, mechanical evaluation of scaffolds in terms of compression and tensile mode showed that samples reinforced with 2 % PLA-CFs had enhanced mechanical properties. Indeed, its tensile strength increased from 123.8 to 247.2 kPa for dry and 18.9 to 48.6 kPa for wet conditions. Furthermore, the tensile modulus associated with both conditions increased from 2.99 MPa and 44.5 kPa to 6.43 MPa and 158.4 kPa, respectively. The results of cell culture studies also confirmed that the prepared composite scaffold exhibited appropriate biocompatibility, cell proliferation and migration. The cell infiltration study of the samples revealed that scaffolds reinforced with 2 % PLA-CFs had significantly better cell penetration and distribution compared with the control ones on both days (7 and 14). [Display omitted] • Short PLA nano/micro fibers were obtained using centrifugal spinning/milling method. • Chopped PLA nano/micro fibers were dispersed inside the chitosan/Gelatin hydrogel. • Adding centrifugal-spun nano/micro fibers, enhanced mechanical properties of composite scaffolds specially at wet condition. • Prepared composite scaffolds revealed improved HDF-GFP+ cells bioactivity and infiltration. [ABSTRACT FROM AUTHOR]

Soil modification is a technique for improving poor soil properties to make them suitable for engineering projects. Regarding the previous studies, various types of stabilisations were used to improve mechanical properties in soil. Several methodologies and experimental tests were used to study the positive and negative effects of utilising fibre on lime/cementmodified soil. This paper reviews the strength behaviour and microstructural properties of Fibre-Reinforced Lime Stabilised (FRLS) soil and Fibre-Reinforced Cement Stabilised (FRCS) Soil. First, the impact of FRLS/FRCS soil on strength behaviour under freeze-thaw conditions, the California Bearing Ratio (CBR) value, and compression/tensile strength are all examined. Then synthetic and natural fibres are compared at the microstructure level. FRCS/FRLS soil has been studied for its influence on geotechnical characteristics such as peak strength, residual strength, ductility, bearing capacity, stiffness, and settlement values. In addition, the micro-level evidence demonstrates that lime/cement affects the interlocking between soil particles and fibre. Although lime/cement improves soil strength by making it solid and compact, it makes stabilised soil brittle. Fibre as reinforcement in lime/cement stabilised soil transforms the brittleness of the soil into ductility. Hence building various infrastructures on poor soils is possible if fibre with lime/ cement is used as an improvement method. Here, these three most used soil additive materials are investigated in terms of strength, microstructural, mineralisation, and some open issues are suggested for further research. [ABSTRACT FROM AUTHOR]

Mortar coatings have a major influence on a building's aesthetics, valorization, and habitability, with significant effects on the mechanical behavior of masonry walls. Multiple types of meshes can be embedded in plaster to enhance both masonry and coating's mechanical behavior, restrain crack formation, enhance the bonding between layers, and increase the wall's seismic resistance. The reinforcement technique has simple execution and is suitable for many applications, including the strengthening of non-load bearing walls, façade performance improvement, and restoration of historical buildings. However, there is an absence of guidelines and specifications for design and execution, resulting in high variability in field applications due to the many variables involved and few in-depth studies. This paper presents a systematic review of the effects of mesh reinforcement in cementitious mortar coatings and its major applications. Mortar and mesh parameters and influences, the status of analytical and simulation models, and suggestions for future research are described. [ABSTRACT FROM AUTHOR]

Current research paper deals with reinforced concrete (R.C.) beams numerical modeling and suggested strengthening procedure if it is required to create an opening within their shear zones. Strengthening is assumed to be achieved during different service load application conditions. Reinforced Concrete beams with rectangular or circular opening in shear zone; as critical regions; sustain two concentrated system of loads are tested till failure before and after performing suggested opening assessing technique by means of Carbon Fibers Reinforced Polymer sheets (CFRP). The main aim of this research is simulating real practice situation where the beam is subjected to service loads, supported temporary by means of hydraulic jacks, opening is created and strengthening is performed then jacking supports are released. Results of achieved numerical nonlinear modeling are introduced and influence of strengthening achieving on improving assessed beams almost structural behavior such as initial cracking loads, load deflection curves, cracking patterns, failure loads & modes for reference (without opening), main un-strengthened control beams, and CFRP strengthened opening beams are introduced and analyzed in details. Some important conclusions & recommendations for designer and executive engineers are stated.

In the present work, an attempt has been made to synthesize metal matrix composite using Al7075 as matrix material with B4C particles as reinforcement using liquid metallurgy technique in particular stir casting process. Microstructural characterization was carried out for the above prepared composites by taking specimens from central portion of the casting by microstructural studies and SEM analysis. Tensile, shear, compression and bending properties of the prepared composite were studied before and after addition of Al7075 particulates to note the extent of improvement. Microstructural characterization of the composites has revealed fairly uniform distribution of B4C particulates and some amount of grain refinement in the specimens. The design and analysis of wing root fitting of on medium fighter aircraft carried out using CATIA V5 and ANSYS workbench software. Finite element method is used for the stress analysis. Calculation of equivalent stress, shear stress and total deformation will be considered under this study. [ABSTRACT FROM AUTHOR]

Seismic performance evaluation is carried out for reinforced concrete bridge columns using both normal (SD400) and high (SD700) yield strength of reinforcement. A total of 12 column specimens are tested under lateral load reversals. Primary design parameters are types of cross-section, yield strength of both longitudinal and lateral reinforcements, longitudinal reinforcement ratio, and vertical spacing of lateral reinforcement. Lateral force-displacement hysteretic response reveals that experimental lateral forces are well above code-specified lateral forces in overall displacement range. Specimens using SD700 show higher lateral force carrying capacity than those with SD400. On the other hand, specimens using SD400 exhibit more ductile behaviour than those with SD700. Deformation capacity is also investigated in terms of displacement ductility and cumulative energy dissipation. Whereas experimental ductility values are in general greater than code-specified values, margin of safety is slightly reduced as yield strength and longitudinal reinforcement ratio increase. It is thus believed that use of SD700 in reinforced concrete columns seems to be promising. [ABSTRACT FROM AUTHOR]

A popular water pipe system used in many countries is one formed by prestressed cylindrical concrete pipes (PCCPs) formed by identical precast moduli joined together in situ. This technology was and still is quite popular in many water supply systems internationally. This technology was mainly selected at the time due to its cost-based comparative advantage. However, over the years, numerous incidents of structural failures have been reported for this type of pipeline, causing, in some cases, serious disruption of the water supply. This study summarizes the results of an experimental investigation on ten (10) PCCP specimens taken from an existing water pipeline with the objective of investigating their bearing capacity under either three-edge bending or internal hydraulic pressure loads. Moreover, there is a need to check the capability of specific retrofitting/strengthening schemes to upgrade this bearing capacity and thus enhance the operational period. Provided that the prestressing wires are fully active according to design specifications, the original specimen performed satisfactorily for the set internal hydraulic pressure limit of 8.5 bar. Specimens retrofitted with either internal or external CFRP or RC jacketing performed satisfactorily for internal hydraulic pressure levels well above this 8.5 bar limit. A critical factor is, as expected, the loss of prestress. [ABSTRACT FROM AUTHOR]

Soil–reinforcement interaction is a major factor in the analysis and design of reinforced earth structures. In current research the effects of attaching elements of different size and numbers as anchors on enhancement of interaction at soil–geogrid interface under direct shear conditions were studied. Poorly and well graded sands (SC & Sf), a high density polyethylene geogrid, anchors with three different size and numbers (layouts) and clamping length of 2 cm from shear surface were used. Samples were prepared dry at a relative density of 80% in a 30 × 30 cm direct shear box and subjected to normal pressures of 12.5, 25 and 50 kPa with the shear load applied at a rate of 1 mm/min. Results of the assessment show that anchored geogrids improve shear resistance at interface mainly due to mobilization of passive soil resistance that is significantly influenced by the magnitude of the normal pressure and the number and size of anchors. Interaction enhancements achieved varied between a minimum of 8% and a maximum of 42%. [ABSTRACT FROM AUTHOR]

Hydrogels show promise in cartilage tissue engineering (CTE) by supporting chondrocytes and maintaining their phenotype and extracellular matrix (ECM) production. Under prolonged mechanical forces, however, hydrogels can be structurally unstable, leading to cell and ECM loss. Furthermore, long periods of mechanical loading might alter the production of cartilage ECM molecules, including glycosaminoglycans (GAGs) and collagen type 2 (Col2), specifically with the negative effect of stimulating fibrocartilage, typified by collagen type 1 (Col1) secretion. Reinforcing hydrogels with 3D-printed Polycaprolactone (PCL) structures offer a solution to enhance the structural integrity and mechanical response of impregnated chondrocytes. This study aimed to assess the impact of compression duration and PCL reinforcement on the performance of chondrocytes impregnated with hydrogel. Results showed that shorter loading periods did not significantly affect cell numbers and ECM production in 3D-bioprinted hydrogels, but longer periods tended to reduce cell numbers and ECM compared to unloaded conditions. PCL reinforcement enhanced cell numbers under mechanical compression compared to unreinforced hydrogels. However, the reinforced constructs seemed to produce more fibrocartilage-like, Col1-positive ECM. These findings suggest that reinforced hydrogel constructs hold potential for in vivo cartilage regeneration and defect treatment by retaining higher cell numbers and ECM content. To further enhance hyaline cartilage ECM formation, future studies should focus on adjusting the mechanical properties of reinforced constructs and exploring mechanotransduction pathways.

This paper presents an exploration of choosing the optimum density for concrete that achieves the best structural performance for two-way slabs made of concrete with fine aggregate in different proportions less than the ratio used in ordinary concrete to produce different densities, by taking advantage of the idea of fine aggregate concrete which considers as light-weight concrete to achieve lighter concrete with higher structural endurance. The experimental program includes constructing and testing five slabs, four of them made of concrete with different fine aggregate radios 75%, 50%, 25%, and 0% to get different densities (2207, 1792, 1536, 1310 kg/m3) as well as another slab made of normal concrete used as a reference slab with a density of 2414 kg/m3. The outcomes reveal that decreasing the density of the slab from 2414 kg/m3 to 1310 kg/m3 by reduction fine aggregate in concrete from 100% to 0% respectively has more effect on the first crack load than that on the ultimate load of two-way slabs as the first crack load decreases with percentages 16.7%, 33.3%, 38.9%, and 61.1% the while the ultimate load decreases with percentages 7.3%, 21.9%, 46.3%, and 56.1%, respectively as compared to the reference (normal wight concrete slab). Also, decreasing the density of the slab made the cracks form and spread quickly and the slab failure tends towards the brittleness, and the cracks diffused and grew faster and wider.