Exploring the Synergy: Experimental and Theoretical Investigation of Steel and Glass Fiber Reinforced Polymer (GFRP) Reinforced Slab Incorporating Alccofine and M-Sand

Introduction: This study investigates the Experimental and Theoretical Investigation of Steel and Glass Fiber Reinforced Polymer (GFRP) Reinforced Slab Incorporating Alccofine and M-sand. Objective: Specific objectives include evaluating the mechanical properties and structural behaviour of steel and GFRP-reinforced one-way slabs and comparing experimental and theoretical predictions. Methods: Four different mix proportions were arrived at, comprising both conventional concrete and Alccofine-based concrete. In each formulation, a combination of normal river sand and M-sand was utilized. Results: Concrete with Alccofine exhibits superior mechanical properties, while M-sand incorporation minimally affects strength but reduces reliance on natural sand. GFRP-reinforced slabs display distinct brittle behaviour with significant deflections post-cracking, contrasting steel-reinforced slabs’ gradual, ductile failure. Discrepancies between experimental data and design recommendations underscore the need for guideline refinement. Conclusion: Alccofine and M-sand enhance concrete properties, but reinforcement type significantly influences slab behaviour. GFRP-reinforced slabs, though exhibiting lower values than steel, offer advantages in harsh environments, warranting further optimization.

A review on machinability of carbon fiber reinforced polymer(CFRP)and glass fiber reinforced polymer(GFRP)composite materials

Fiber reinforced polymer(FRP) composite materials are heterogeneous and anisotropic materials that do not exhibit plastic deformation. They have been used in a wide range of contemporary applications particularly in space and aviation,automotive,maritime and manufacturing of sports equipment. Carbon fiber reinforced polymer(CFRP) and glass fiber reinforced polymer(GFRP) composite materials,among other fiber reinforced materials,have been increasingly replacing conventional materials with their excellent strength and low specific weight properties. Their manufacturability in varying combinations with customized strength properties,also their high fatigue,toughness and high temperature wear and oxidation resistance capabilities render these materials an excellent choice in engineering applications.In the present review study,a literature survey was conducted on the machinability properties and related approaches for CFRP and GFRP composite materials. As in the machining of all anisotropic and heterogeneous materials,failure mechanisms were also reported in the machining of CFRP and GFRP materials with both conventional and modern manufacturing methods and the results of these studies were obtained by use of variance analysis(ANOVA),artificial neural networks(ANN) model,fuzzy inference system(FIS),harmony search(HS) algorithm,genetic algorithm(GA),Taguchi's optimization technique,multi-criteria optimization,analytical modeling,stress analysis,finite elements method(FEM),data analysis,and linear regression technique. Failure mechanisms and surface quality is discussed with the help of optical and scanning electron microscopy,and profilometry. ANOVA,GA,FEM,etc. are used to analyze and generate predictive models.

Advanced Welding Technology for Highly Stressable Multi-Material Designs with Fiber-Reinforced Plastics and Metals

Organic sheets made out of fiber-reinforced thermoplastics are able to make a crucial contribution to increase the lightweight potential of a design. They show high specific strength- and stiffness properties, good damping characteristics and recycling capabilities, while being able to show a higher energy absorption capacity than comparable metal constructions. Nowadays, multi-material designs are an established way in the automotive industry to combine the benefits of metal and fiber-reinforced plastics. Currently used technologies for the joining of organic sheets and metals in large-scale production are mechanical joining technologies and adhesive technologies. Both techniques require large overlapping areas that are not required in the design of the part. Additionally, mechanical joining is usually combined with “fiber-destroying” pre-drilling and punching processes. This will disturb the force flux at the joining location by causing unwanted fiber- and inter-fiber failure and inducing critical notch stresses. Therefore, the multi-material design with fiber-reinforced thermoplastics and metals needs optimized joining techniques that don’t interrupt the force flux, so that higher loads can be induced and the full benefit of the FRP material can be used. This article focuses on the characterization of a new joining technology, based on the Cold Metal Transfer (CMT) welding process that allows joining of organic sheets and metals in a load path optimized way, with short cycle times. This is achieved by redirecting the fibers around the joining area by the insertion of a thin metal pin. The path of the fibers will be similar to paths of fibers inside structures found in nature, e.g. a knothole inside of a tree. As a result of the bionic fiber design of the joint, high joining strengths can be achieved. The increase of the joint strength compared to blind riveting was performed and proven with stainless steel and orthotropic reinforced composites in shear-tests based on the DIN EN ISO 14273. Every specimen joined with the new CMT Pin joining technology showed a higher strength than specimens joined with one blind rivet. Specimens joined with two or three pin rows show a higher strength than specimens joined with two blind rivets.

Experimental Investigation of Natural Fiber Reinforced Polymers

The potential usage of virgin Low density polyethelyne (LDPE) reinforced with different concentrations (2%, 5% and 6% by weight) of treated rice straw with different lengths (2 mm, 4 mm and 6 mm) is investigated to produce high value products that have technical and environmental demand. The two treatment methods used for rice straw are alkali and acidic treatments of rice straw. The removal of impurities and waxy substances from fiber surface avoid creation of rougher topography after treatment and improves the quality of fiber, also content of hemi cellulose and lignin decrease so increase effectiveness of fiber due to dispersing of fiber in matrix. The reinforcing material is embedded in the matrix material to enhance tensile and flexural behaviors of the synthesized composite. The result of investigating these two mechanical properties, using statistical analysis & design of experiments, showed an enhancement in the mechaniccal properties of the virgin polymer composite compared to the virgin polymer. The flexural stress of the composite increased three times the virgin flexural stress, while the tensile stress increased eight times the original tensile stress.

Reinforcement of Plastic Waste with Treated Natural Fibers

Plastic wastes are a major environmental concern that needs to be dealt with to minimize the amount of municipal solid waste and depletion of natural resources thus enhancing the sustainability concept for future generations. The objective of this study is to enhance the properties of plastic products using plastic wastes reinforced with treated natural fibers such as rice straw as well as carbonized rice straw, using a simple and efficient technology.

Flexural Experimental Study on Continuous Reinforced Concrete Beams Strengthened with Basalt Fiber Reinforced Polymer/Plastic

This paper discusses a new fibrous composite known as continuous basalt fiber reinforced polymer /plastic(BFRP).Compared with other fiber reinforced polymer/plastic,BFRP has many advantages,such as ductility,high thermal resistance,corrosion resistance and economic cost.To test mechanical properties and failure modes of flexural members strengthened with BFRP,flexural experiment is conducted on four two-span T-section continuous beams strengthened with BFRP and one un-strengthened comparative beam.The experimental result shows that the strengthened beams perform remarkably in terms of yield strength,ultimate strength and ductility.BFRP has good prospects in retrofitting and strengthening of concrete structures which require good ductility and corrosion resistance.

Natural Composite Material from Steelwool or Luffa cylindrica under Natural, Rigid and Flexible Resin

In a changing world with a high interest in new ecomaterials, natural fibers such as the steelwool or Luffa cylindriea appear in new presentations and mixing with other materials to develop better opportunities to replace synthetic fibers. This work presents a research on the use of steelwool fiber for composite materials, on the basis of the physical properties, that generate conditions of mixing with three binders （matrix） natural： the rosin, artificial hard： polyurethane resin and artificial flexible： flexible twin resin （epoxy） and finally a polyester resin to make a comparison with other major resins. A testing of compression and tension is carried out to the materials analyzed, obtaining three types of composite materials by the above mentioned binders and three proposed presentations of fiber （complete, tissue and ground）. The test tube in tension with polyester resin presented a high rigidity and a percentage of deformation of 14%, resulting in less distortion than the woven with resin polyurethane with 12% of deformation. The presentation with resin polyurethane presented greater resistance to compression, because the resin acts as a sponge absorbing the energy of charge and the join of particles is larger than the other presentations generating greater cohesion among them and avoiding its rupture easily for a load of 2,000 kg. The presentation that is least resisted was the woven in two resins in the stage of energy absorption of load where polyurethane is 800 kg and the flexible twin is 850 kg, because the form of woven fiber distribution creates spaces where there are more resin than fiber.

SUPER-THIN COATING MATERIAL FOR HIGH-GRADE HIGHWAY

The road surface of cement concrete in highway is easily cracked and even destroyed due to inhomogeneous subsiding of the road foundation. In this work, a super-thin-coating material is prepared in order to repair the destroyed thin road surface, in which polymers and steel-fiber are added into ordinary concrete to form a steel fiber reinforced polymer-cement-based composite, the composite was successfully used to repair road surface. Microstructure and mechanical properties of the composites are measured and analyzed.

玻璃纤维增强聚合物管约束高强混凝土柱轴压试验研究

为研究玻璃纤维增强聚合物管约束高强混凝土柱的轴压性能,设计了6个不同长细比的试件并对其进行了轴心受压试验,分析了其破坏过程及破坏形态、承载力、位移、荷载-位移曲线、骨架曲线、荷载-应变曲线。研究表明:玻璃纤维增强聚合物管约束混凝土柱轴压承载性能优异,随着长细比的减小,试件的轴压承载力提升显著;加载后期,该组合结构的破坏模式为玻璃纤维增强聚合物管发生环向破坏,内部混凝土被压溃;玻璃纤维增强聚合物空管轴压承载力相对较低,破坏时脆性特征明显;随着长细比的减小,玻璃纤维增强聚合物管约束高强混凝土柱的承载力和刚度逐步增加,长细比对结构的承载能力影响显著。研究结果对玻璃纤维增强聚合物管约束高强混凝土柱的理论研究和工程应用具有一定的指导意义。

FRP布材增强钢筋混凝土桩水平承载性能研究

纤维增强复合材料(FRP)由于其轻质高强的优点被广泛应用于抗震加固、结构补强等实际工程中,但有关FRP增强混凝土桩水平承载性能的研究较少。为了研究不同FRP布材加固混凝土桩承载特性问题,通过室内模型试验对FRP布桩(普通钢筋混凝土桩身包裹FRP布材)的水平承载规律进行研究,探究了不同包裹层数、不同FRP布材类型、不同布材混合包裹对钢筋混凝土桩承载性能的影响。同时利用ABAQUS软件建立FRP布桩三维有限元模型,对每种工况进行数值模拟。结果表明,FRP布桩的水平承载性能随着包裹层数的增加而提升,提升效果与包裹层数之间并不存在正比例关系;不同布材类型的FRP布桩中,CFRP布对FRP布桩的水平承载性能提升效果最优;混合包裹(CFRP+GFRP)的提升效果要略优于包裹2层GFRP布。

高性能高分子材料体系自立自强发展战略研究

高性能高分子材料具有高强高模、高绝缘、耐腐蚀、耐辐照或绿色低碳等特点,是保障国家安全和国民经济发展的战略性材料之一,广泛应用于航空航天、电子电器、生物医疗等重要领域。本文系统梳理了高性能树脂及工程塑料、有机纤维、生物基树脂及可降解材料、特种橡胶及弹性体四大类高性能高分子材料中的重点品种,分析了国内外重点品种的发展现状和特点。研究发现,目前我国在高性能高分子材料方面已建立起比较完备的化工原料–合成–加工改性–制品应用上下游产业体系,但同时也存在关键原料保障不足、产品应用开发有待拓展等问题。在此基础上,从加强技术创新、推进关键原料保障、组建创新联合体等方面提出对策建议,以期为我国高性能高分子材料体系发展提供参考。

防弹头盔选材及结构设计对其防护性能的影响

防弹头盔是单兵作战时不可缺少的重要防护装备。防弹头盔的防护性能主要受其选材和结构设计的影响。通过总结国内外防弹头盔的选材,结构设计及对应防护机理的相关研究进展,对目前防弹头盔广泛使用的纤维增强复合材料的纤维类型和织物组织结构进行了探讨;概述了现有防弹头盔的盔体、紧固和减震等各方面的结构设计,并通过总结测试实验和仿真模拟,多角度分析了其防护性能。考虑到复杂多变的战场环境,未来的防弹头盔的材料研发和结构设计要向兼具高防护性能和轻量化发展,还需集成更多的智能化装备。

冰球和钨珠非正冲击下T800-CFRP层合板损伤特性的研究

通过试验和仿真相结合的方法研究了T800碳纤维增强复合材料(CFRP)层合板在冰球和钨珠非正冲击作用下的损伤特性。首先开展了冰球和钨珠在给定工况下高速撞击T800-CFRP层合板试验,以此对仿真模型的有效性进行验证;然后讨论了T800-CFRP层合板在两种冲击体以不同冲击能量与冲击角度作用下的损伤特性及其差异性。研究表明:钨珠在冲击能量较低时就能对层合板造成穿孔损伤,但随着冲击能量增大层合板的损伤程度呈下降趋势;冰球对层合板造成损伤的冲击能量阈值与钨珠的相比要高很多,且随着冲击能量的增加损伤程度明显加剧;钨珠在冲击角度为45°和60°时造成的损伤与正冲击的情况相比要更加严重,而冲击角度为30°时造成的损伤却小于正冲击的情况;冰球冲击时,层合板的损伤程度随冲击角度的增加而减小。该研究有助于深化对T800-CFRP层合板在冲击载荷作用下的损伤与破坏行为的认识,具有重要的科学意义和工程应用价值。

考虑切削能耗和表面质量的碳纤维增强树脂基复合材料加工工艺参数优化决策

碳纤维增强树脂基复合材料(CFRP)二次加工能耗与质量的影响要素相比于传统材料加工更为复杂,导致现有相关经验公式难以适用。基于此,以CFRP二次加工的切削力分析为切入点,对考虑能耗和质量的CFRP加工工艺参数优化决策问题开展研究。首先分析纤维方向角对CFRP加工形式的影响,推导了切削力模型;然后建立了以切削三要素和纤维方向角为变量,以切削能耗和表面粗糙度为目标的多目标优化模型,并提出了多样化突变驱动的粒子群优化算法(DM-PSO)与层次分析法(AHP)集成的工艺参数优化决策方法;最后通过铣削试验设计验证了上述模型和方法的可行性和优越性。

纤维复合材料在调水工程长输管道中的应用

调水工程长距离输水管道的材料选择,对工程成本和输水线路的安全有着重要影响。纤维复合材料具有轻质高强、内壁光滑、耐腐蚀性好等特点,正逐步应用在输水管道中。文章分析了影响长距离输水管道材料选择的主要因素,介绍了钢管、球墨铸铁管、混凝土管等传统输水管道的材料特性,阐述了纤维复合材料在输水管道中的应用,重点分析了玻璃钢夹砂管的发展和特点,最后对纤维复合材料输水管道在产品升级、施工技术、安全防护和质量管理四个方面的发展进行了展望。

基于纤维混凝土材料试验的套拱加固隧道地震响应模拟

以一座山岭隧道为背景,选取钢纤维、玄武岩纤维、碳纤维为掺料进行纤维混凝土材料试验并确定纤维最佳体积掺量;结合试验数据与塑性损伤数值模拟结果,分析地震作用下有无纤维混凝土套拱加固隧道结构响应情况。结果表明:无套拱加固时衬砌拱脚、拱肩、拱腰处易发生拉裂损伤,拱顶与仰拱中心、左右拱肩的相对位移均较大。三种纤维混凝土套拱加固后,衬砌-套拱叠合结构拱腰、拱肩处损伤均有所改善,拉裂损伤向两端发展的趋势得到抑制;拱顶与仰拱中心,左右拱肩的相对位移较无套拱加固时有所降低,隧道结构稳定性提高。综合考虑衬砌损伤与测点位移,体积掺量为1.5%的钢纤维混凝土套拱加固效果最佳。

FRP复合材料在桥梁工程中的发展与应用

纤维增强聚合物(FRP)是一种由塑料基体和纤维增强材料组成的复合材料,具有轻质高强、抗腐蚀和耐久性等优点。在土木工程领域,尤其是桥梁工程中,它具有广泛的应用前景。该文综述了FRP复合材料的性能、结构和应用特点,并重点探讨了其在桥梁结构加固、竖向受力构件、劲性结构、预应力筋以及桥面板等领域的研究进展。在此基础上,指出了FRP复合材料存在的问题并展望了发展的主要方向。

FRP筋模块化夹片锚具设计及试验研究

纤维增强复合即FRP材料属于各向异性材料,需要针对FRP的特性开发新的锚固系统。与传统FRP锚固方式不同,FRP筋模块化夹片锚具是将FRP筋、多孔切片铝套以及夹片作为一个标准模块,并将其压入锚杯的模块安装孔内。根据实际工况,在锚杯上增加或减少模块安装孔的数量,从而达到拉索的使用要求。利用ANSYS Workbench有限元软件,对模块化锚具的内锥倾角、夹片与锚杯的角度差、锚固长度、FRP筋材间距、夹片预紧力等参数进行分析,提出了一种新型模块化锚固形式,并通过试验的方法来测试模块化夹片锚具的锚固性能。结果表明,采用模块化夹片锚具对FRP筋进行锚固的方法是可靠的,本文开发的模块化夹片式锚具的锚固效率超过90%,有利于锚固设计,降低成本。

不同纤维合成高分子增强材料在田径运动器材中的应用研究

从碳纤维、玻璃纤维和高强高模合成纤维这3种纤维增强塑料出发,借助不同纤维进行高分子塑料的增强改性,探究这些纤维增强塑料材料在体育领域中的性能优势和成型工艺。主要研究了3种纤维合成的高性能高分子塑料材料在跳高撑杆、自行车、田径服等田径体育器材领域的应用情况。以期在优化塑料材料综合性能的同时,提高田径体育器材的安全性和使用寿命。