Behaviour of Composite I-Beams Under Crushing and Bending Modes

In structural applications, beam is one of the most common structural members that have been considered in design. This paper is intended to provide tools that ensure better designing options for composite laminates of I -beam. In this Paper an analytical method & FEM approach calculating axial stiffness , Axial stress ,Axial strain of flange and web laminates. The results show the stacking sequence and fiber angle orientation strongly affects strength of composite I-beam.

The worldwide demand for wood has doubled in the last 30 years to approximately 3.5 billion m 3 per annum, driven by the increase in world population and improvements in general living standards. Forest product industries previously relied on an inexhaustible supply of high quality log to produce large volumes of fine sawn timber, but now old growth timber is a declining resource. The reduced supply of good quality timber coupled with the increased demand for structural wood products led to the development of Engineered Wood Products (EWP), which include Glued laminated timber (Glulam), Parallel Strand Lumber (PSL), Laminated Strand Lumber (LSL), Laminated Veneer Lumber (LVL), Oriented Strand Board (OSB), Plywood, Structural insulated panels (SIP) and wooden I-beams all used in the construction industry. This research describes the fabrication and investigation of new engineered wood products called Composite Insulated Beams (CIB). The CIBs were tested to determine their structural performance, long term durability, thermal and dynamic behaviors. CIBs combine the efficiency of sandwich panels with existing engineered wood products to produce new, competitive and cost effective EWP with improved structural value and durability. The CIBs consist of a composite frame with I or rectangular cross-sections. Each frame is constructed by bonding at least two webs to the top and bottom flanges. The interior of a frame could be filled with a material which would enhance thermal properties, structural performance and long term durability of the beam. Three combinations of materials were used in beam frame construction, timberflanges with OSB-webs, timber-flanges with plywood-webs, LVL-flanges with plywood-webs. Five different beam designs have been manufactured in each of the three material combinations and all were then tested to determine their engineering

2011

Effect of geometry on crushing behavior, energy absorption and failure mode of woven roving jute fiber/epoxy laminated composite tubes were experimentally studied. Investigations were carried out on three different geometrical types of composite tubes (circular, square and radial corrugated) subjected to axial compressive loading. It was observed in axial crushing study that the load bearing capability is significantly influenced by corrugation geometry. The influence of geometries of specimens was supported by the plotted load – displacement curves of the tests.

2014

Researchers all over the world are attempting to develop high performance concretes by using fibers in concrete up to certain proportions. The present work deals with the results of experimental investigations on glass fiber reinforced concrete. Effect of these fibers on strengths of concrete are studied. Fiber content varied from say (1.0%, 2.0%, 3.0%, 4.0 % & 5%) by weight of cement. Various strengths considered for investigation are compressive strength and flexural strength for glass fiber reinforced concrete. All the specimens were water cured up to 28 days and tested subsequently. Result data clearly shows percentage increase in 28 days Compressive strength and Flexural strength for M-20 Grade of Concrete. A comparison of results of fiber reinforced concrete with that of normal concrete showed the significant improvements in the results of compressive strength and flexural strengths. The results of strengths of hardened concrete obtained experimentally for fibers reinforced co...

2014

Nowadays modern architecture demands more transparent building elements. The composite elements allow the best of the characteristics of two different materials to be brought together for a common purpose. This was one of the major reasons for carrying out the presented experimental research. This paper focuses on the analysis of experimental test of timber-glass I-beam on four–point bending tests. The work is being carried out as part of the EU Wood Wisdom-Net research project, with participants from Austria, Brazil, Chile, Germany, Turkey, Sweden and Slovenia. Contents

Journal of Materials Research and Technology, 2019

Epoxy composites reinforced with 10, 20 and 30 vol% of a natural lignocellulosic fiber, the mallow fiber, were investigated for mechanical properties associated with Izod notch toughness and flexural resistance. For Izod tests, 150 × 120 × 10 mm plates and for three-point bend tests, 150 × 120 × 6 mm plates were fabricated in a steel mold by mixing aligned fibers with necessary percentage of diglycidyl ether of the bisphenol an epoxy resin hardened with triethylene tetramine. Each plate was kept under load of 5 ton during 24 h of curing at 25 • C. Both Izod and bend specimens were machined from corresponding plates and tested according to ASTM D256 and ASTM D790 standards, respectively. The results showed that composites with 20 and 30% of mallow fibers display a more effective reinforcement, with the predominance of fracture mechanisms, such as fiber rupture and interfacial detachment between the fibers and the matrix. The analysis of the results of both impact energies and flexural properties, was performed by the ANOVA statistics and Tukey test. Based on a 95% confidence level, the Tukey test showed that the 30 vol% of mallow fiber reinforced epoxy composites has the best performance, achieving the highest values of energy absorption, maximum flexural strength and rupture modulus. These results revealed that mallow fiber reinforced epoxy composites have promising applications as engineering materials.

Silicon, 2019

The manufacturing of the composite material has been developed tremendously over the years due to its superior properties like low density, stiffness, lightweight and excellent mechanical as well as physical properties. These exceptional properties of composite materials have found its applications widely in aerospace, automotive, marine and many more engineering areas. The synthesis of the varieties of composites is continuously lookout without compromising its mechanical and physical properties. This paper deals in with synthesis as well as mechanical properties (Tensile Strength, Flexural Properties and Fatigue) of Glass-Epoxy as well as Glass-Vinyl Ester composites. The resins used in combination of composites were epoxy as well as Vinyl Ester while the reinforced material was glass fibers. The ultimate tensile strength in Glass-Epoxy composite was observed from 330 to 370 MPa while it was 270 to 330 MPa for Glass-Vinyl Ester Composites. Glass-Epoxy composites showed a 32% increase in flexural strength due to post-curing strength while it was 16% in case of Glass-Vinyl Ester Composites. The results of the fatigue analysis of composites indicate faster growth of cracks and defects at higher frequencies which results in a rapid drop in stress levels in the test specimen. The statistical analysis was carried out to establish mutual correlation among mechanical as well as physical properties.

Construction and Building Materials, 2010

This paper presents the structural behavior of an innovative hybrid Fiber Reinforced Polymers (FRP) beam consisting of carbon/glass fibers and vinyl-ester resin. The advanced feature of this hybridization is the optimum use of carbon and glass fibers in the flanges to maximize structural performance while reducing the overall cost by using only glass fibers in the web section. A series of beam tests were conducted under four-point bending varying ratio of flange to web width (b f /b w) and volume content of carbon and glass fiber in the flanges. Experimental investigations revealed that the ratio of flange to web width of hybrid FRP I-shaped beams plays an important role in their structural behavior. Small flange beams (b f /b w = 0.43) showed stable and linear behavior under bending moment and failed in a brittle manner by delamination of the compressive flange at the interfacial layers while wide flange beams (b f /b w = 1.13) exhibited unstable and nonlinear behavior in the buckling and post-buckling region leading to delamination failure of the compressive flange. The experimental and analytical results discussed in this paper emphasize on the best composition of carbon and glass fibers for the optimum design of such hybrid beams. It is found that the maximum strength of hybrid FRP beams can be obtained with the volume content of carbon fiber to be 25-33%. Furthermore, the results of this study show the potential of applying hybrid FRP beams for bridge components.

Composites are a type of material that generally combines two materials yielding mechanical properties that are different than its constituent parts. These constituents are classified as either a fiber or a matrix. The objective of this project is to create a carbon-fiber composite I-beam that meets the specifications of the SAMPE student bridge competition. The I-beam consists of carbon fiber unidirectional and woven laminas, as well as aluminum honeycomb and high density polystyrene foam to stiffen the structure. The bridge contest rules limit the dimensions and weight of the bridge. The cross-section must be within 4 inches x 4 inches with a minimum length of 24 inches, and a maximum weight 600 grams. Theoretical stress and deflection analysis of the bridge was performed using MSC Nastran finite element software. All bridges were manufactured using a wet layup technique and cured under vacuum. Composite bridges were tested using the Instron machine belonging to the architectural engineering department at Cal Poly San Luis Obispo. Through analysis and testing, it was determined that web stability was the driving failure mode to design for. Our final bridge failed under 3000 lb f due to buckling of the web directly beneath the applied load. Our first and fourth iterations saw twisting of the flanges because of the lack of stiffness in the flange structure. Our second bridge iteration had the highest strength-to-weight ratio and also took the highest load (3100 lb f ) before failing. Based on testing and performance at the SAMPE competition, there are many aspects of this project that can be improved, most importantly through manufacturing techniques. Use of an autoclave as well as using metal molds for curing the beam will dramatically increase load carrying capability.

Civil Engineering Journal, 2020

In this study, the effect of glass fiber reinforced polymer (GFRP) section and compressive strength of concrete in composite beams under static and low velocity impact loads was examined. Modeling was performed and the obtained results were compared with the test results and their compatibility was evaluated.‎ Experimental tests of four composite beams were carried out, where two of them are control specimen with 20 MPa compressive strength of concrete deck slab and 50 MPa for other. Bending characteristics were affected by the strength of concrete under impact loading case, as it increased maximum impact force and damping time at a ratio of 59% and reduced the damping ratio by 47% compared to the reference hybrid beam. Under static loading, there was an increase in all the parameters, including the maximum load, ductility, and stiffness. Mid-span deflection was reduced by 25% under static and impact loads. A finite element analysis was performed by using the ABAQUS software. The mi...