Papers by Keyword: Composite Beam

Abstract: A total of seven simply supported composite specimens are tested under concentrated load at the mid-span of the beam to investigate the strength of specimens to resist the applied load if web buckling take place. A novel technique of using a corrugated CFRP struts to strengthen the web of the steel girder is presented in this study. This technique provides two layers of CFRP laminate which are from biaxial fabrics to provide a knitted material that can undergo the complex state of stress in the web. The studied specimens are divided into two groups in addition to the control specimen having the same length. There are three specimens in each group, these specimens have different castellation ratios of (33.3%, 43.3% and 54.3%), the first group is identical to the second one except that the second group was strengthened with the proposed CFRP corrugated struts while the first one kept unstrengthen as a reference. Composite beams have a vertical stiffener at the action area above the supports. The reference group showed decrease in deflection of (11.11, 20 and 26.67) % for (33.3, 43.3 and 54.3) castellation ratio while strengthened girders record (13.75, 6.11 and 13.93) % for the same opening depths, compared to the control specimen. In addition, CFRP struts decrease the web buckling from (1.6, 2.9 and 83.33) to (0.8, 0.4 and 0.3) mm for beams with castellation ratio of (33.3, 43.3 and 54.3) respectively.

Abstract: In recent years, thin-walled, cold-formed steel (CFS) structural members have gained expanding use in building construction and various sorts of structural systems [1,2,3].The utilization Cold-Formed Steel (CFS) structures has become progressively popular in different fields of building technology. The reasons behind the developing popularity of these products include their ease of fabrication, high strength/weight ratio and suitability for a wide range of applications. These advantages can result in more economic designs, as compared with hot-rolled steel, especially in short-span applications. In this project work attempt has been made to use Cold formed steel section as replacement to conventional steel reinforcement bar.

Abstract: The cost-efficient field design is very important in the civil engineering. Therefore, the cold-formed steel structures (CFS) are preferred for construction. A Sophisticated CFS structure which uses a Cellular Concrete is implemented in this paper. The utilization Cold-Formed Steel (CFS) structures have become increasingly popular in different fields of building technology. The reasons behind the growing popularity of these products include their fabrication ease, high strength/weight ratio and suitability for a wide range of applications. These advantages can result in more economic designs, as compared with hot-rolled steel, especially in short-span applications. In this project work an attempt to use a Cold formed steel section as replacement to conventional steel reinforcement bar has been made.

Abstract: The numerical analysis model and analytic formula, concerning flexural-tensile composite modulus of steel deck paving materials, were established with five-point loading composite beams, in order to explore the modulus value of steel deck paving materials. Regarding the three typical asphalt pavement material such as SMA10, GA10 and EA10, the composite modulus of paving material was calculated by analyzing stepwise loading data, and a universal flexural-tensile composite modulus range is proposed: SMA10 is 500 ~ 550MPa, GA10 is 500 ~ 600MPa, EA10 is 650 ~ 700MPa. The results show good agreement between the modulus of the numerical analysis method and analytical formula method. The proposed analytical formulas can calculate the flexural-tensile composite modulus more easily according to the actual load conditions, and the modulus value played a significant role in guiding the design and mechanical analysis of steel deck pavement system.

Abstract: In this study we investigated the dynamical behavior of aircraft wings and using piezoelectric actuation we implemented active vibration control. The aircraft wing is modeled as a thin-walled composite beam having a cross section of diamond shaped. The dynamic response of the beam under varying proportional and velocity feedback gain parameters is obtained and shown to be enhanced with optimal control procedure, minimizing the control effort and response.

Abstract: This work presents the experimental tests carried out to evaluate the behaviour of different types of shear connectors proposed for cold formed steel (CFS) section integrated with ferrocement slab as potential used for composite beam. Ten push-out test specimens of cold-formed steel lipped channel sections connected with ferrocement slab were tested. Three types of shear connectors were studied comprised of bolts, self-drilling-screw and bar angle. The connection behavior is analysed in terms of its load-slip relationship and the failure mode. The parametric studies were performed to investigate the effect on the shear connector’s capacity by varying the number of layers of wire mesh used in ferrocement slab and types of shear connector used. A theoretical analysis (Eurocode 4) was carried out to verify the experiment results. The results show that the experimental and theoretical proved to have good agreement with each other.

Abstract: The timber-concrete composite (TCC) beam is a new type of structural member, which formed by combing a timber beam and an upper concrete flange using different types of connectors. Compared with the traditional timber beam, the bending and stiffness of the composite beam is proved. In composite structure, the important factor of the structure is the shear connector. So structural efficiency of a TCC highly depends on the stiffness of the interlayer connection. This paper presents a survey on the state-of-the-art of shear connectors for TCC beam research in the past and recent years. And put forward to the subsequent study of shear connectors in TCC beams.

Abstract: The optical system with multiple light sources of steady solar simulator being developed in our country as the research object, analysis on the from and effect of spot convergence when the steady solar simulator in different spatial positions, by using the method of numerical calculation and software simulation, to determine the maximum position deviation which is allowed by the source. The research results show that: the spatial location of sources to solar simulator is the key factor to influence the shape and energy distribution of composite beam that may offer some references and gist for designing the light control system of solar simulator, anglicizing the spot data and determining the key parts of processing precision.

Abstract: The theme of the present work is the analysis of the guided waves propagation along a flat, narrow composite plate (beam). The investigated structure is made of the multi - layered composite material (carbon fabric with epoxy resin). The applied material posses the quasi - isotropic mechanical properties. The guided waves are generated with the use of the piezoelectric activator. The finite element method is used in order to carried out the computer simulations. The plain state of the strain is assumed. The computations are performed for the intact and the damaged structure. In the case of the damaged structure the received signal (voltage) is significantly different in comparison with the intact structure. The qualitatively similar results are obtained from the experimental investigations.

Abstract: In this study, free vibration responses of a carbon nanotube reinforced composite beam are investigated. The governing differential equations of motion of a carbon nanotube (CNT) reinforced composite beam are presented in finite element formulation. The validity of the developed formulation is demonstrated by comparing the natural frequencies evaluated using present FEM with those of available literature. Various parametric studies are also performed to investigate the effect of aspect ratio and percentage of CNT content and boundary conditions on natural frequencies and mode shapes of a carbon nanotube reinforced composite beam. It is shown that the addition of carbon nanotube in fiber reinforced composite beam increases the stiffness of the structure and consequently increases the natural frequencies and alter the mode shapes.