Papers by Keyword: Bending Test

Abstract: Experimental study of the damage energy is a reproduction of the GFRP vessels’ slamming in the sea. The investigation was carried out to the laboratories by the construction of two types of GFRP panels: viscoelastic and non- viscoelastic modified. Through a bending test, the data collection was developed to get the measurement of the variables in key points. The obtained results showed an expected behavior because the modified specimens were able to spread the force induced from the center to the edges. Besides, the damage energy in the modified panels return in bigger amounts than the unmodified. Flexibility demonstrated a higher rate of increase in the unmodified panels, indicating that the viscoelastic layer contributed to the stiffness increment in the modified panel. In conclusion, viscoelastic materials help to dissipate the energy absorbed by the structure, elongating the lifetime. Also, this study expands the basic knowledge of viscoelastic materials’ behavior in the GFRP planing hull vessels.

Abstract: Materials of thermoplastic polymer when they break is usually thrown away, or is recycled which requires a long process. The purpose of this study is splicing the broken thermoplastic polymer using hot gas hand welding with different variations of welding wire/electrodes. Materials of thermoplastic polymer used are Polyethylene (PE), Polypropylene (PP), and Polyvinyl chloride (PVC) by using welding wire like the three materials. The method is carried out by using hot gas hand welding, there are two materials that cannot be connected, namely PE with PVC welding wire, and PP with PVC welding wire. The permeable liquid penetrant test is PP with PE welding wire, and PVC with PE welding wire. The longest elongation is PE with PE welding wire is 15.96% and the best of bending result is PVC with PVC welding wire reach value 181.2 kgf/mm². The microstructure was all described in Scanning Electron Microscopy (SEM) observations.

Abstract: In recent years, the studies on producing data on physical and mechanical properties of Malaysian timber specimens have evolved from small clear specimen to structural size specimen, where most of the research method was based on the American Standard Testing Manual ASTM D198. Numerous data regarding mechanical properties on structural size specimen have been produced through this method, such as bending and compression test. Unfortunately, studies on shear properties on structural size timber are very scarce. It has reviewed that the global timber researchers are focusing to produce data on shear properties of European timber species such as Oak, Spruce and Pine where both shear strength and shear modulus data were obtained from bending and torsion test. Furthermore, from the review of the existing literature, it is clear that there is no proper studies focusing on development of shear properties of Malaysian tropical timber, especially torsion test in accordance with EN 408:2010. Therefore, the aim of this study is to investigate the shear properties (shear strength and shear modulus) of Malaysian Tropical Timber in large size.

Abstract: For structural health of mechanical structures, non-destructive detection and material defect characterization represent the main useful tools for mechanical decay prediction caused by local composite damage phenomena. In this work, internal delamination due to alternate bending were characterized in flat specimens, performing fatigue and static tests, coupled with thermographic, optical, and ultrasonic analysis for damage detection and evolution purposes. Damage to rupture behavior of CFRP material through mechanical tensile tests is performed on several samples and non-destructive inspection procedures are optimized during successive HCF tests to detect in real time local compliance variations and damage initiation. Thermographic continuous monitoring and occasional ultrasonic analysis are implemented to analyze composite anomalies during fatigue life and to elaborate a procedure for identification of delamination induced damage before failure. IRT and UT results are computed with MATLAB analysis for damage evaluation with strain and compliance data acquired during tests.

Abstract: In the field of economic and ecological material research which can replace the composite material currently used in several fields such as glass wool, research leads to a comparison of the mechanical properties and the quality of plates made from recycled materials with those of glass wool, in particular in terms of surface condition and geometric precision thus. In this study, we recycled and used damaged wool fibers in a composite material; the results showed that the new product has mechanical characteristics similar to those of fiberglass composite materials. The recycling of wool fiber reduces the cost of a product made of composite materials, with the possibility of a later study of the machinability of the plates made from this material and its use in various sectors.

Abstract: This work presents the analysis of the influence of several material input data to the FE results of the forming process of fiber reinforced thermoplastics within a sensitivity study. The *Fabric material model of Abaqus/Explicit is used for the description of the shear, tensile and compression behavior. It is a test-data based model. The bending behavior will be modeled with beam elements. The interaction between input data will be analyzed and its influence onto the FE forming results and FE analysis of material tests like bias-extension-test, compression and bending test with focus on interactions of input data and test procedure itself.

Abstract: This paper focuses on the determination of the flexural strength of thin slabs made of the Ultra High Performance Fiber Reinforced Concrete (UHPFRC). The load-bearing capacity in bending of elements reinforced only with steel fibers (used as a scattered reinforcement) is primarily influenced by the orientation and distribution of the fibers. A size-effect occurs by these elements. Some special bending tests were executed within the development of precast bridge deck segments for an innovative timber-concrete composite bridge system. The bending tests were executed on the slab strips under similar boundary conditions as by the bridge deck segments. The slab strips of various thickness of 40, 50, 60, 70 and 80 mm were tested in 4-point bending tests with span 1900 mm and in 3-point bending tests with span 600 mm. Half of the test specimens was tested in casting position, the other half was tested upside down. The obtained values of the flexural strength were compared to values from reference bending tests of the beams 150 x 150 x 700 mm, 100 x 100 x 400 mm and 40 x 40 x 160 mm. An influence of the different size of the tested specimen, of the slab thickness, of the span size and of the positioning of the slab with respect to the direction of casting on the flexural strength are evaluated. The experiments are further supported by numerical simulation.

Abstract: The tensile and bending properties of composite materials with geopolymer matrix reinforced by layers of basalt plain weave fabric were investigated experimentally. We present the results of the quasi-static tensile tests and the quasi-static and cyclic three-point bending tests. The composite panels were made by hand laying with subsequent vacuuming. The plates were stayed in a compression press and left in a compressed state for a month. After 5 months the samples were made from the plates and subjected to tests. The material behaves as linear almost to the failure, which occurred at tensions of about 100 MPa. The elastic modulus is between 6000 and 7000 MPa.

Abstract: To evaluate the bending performance of a steel fiber-reinforced concrete shield segment, bending testing was conducted on prism specimens and full-scale segments with 30 kg/m³ and 40 kg/m³ steel fiber. The results show that, with increasing fiber content, the ultimate and equivalent flexural strengths increase, while the flexural toughness of the prism concrete specimen increases by approximately 15%. With increasing fiber content, the flexural capacity of the shield tunnel segment increases, the peak load increases by 24%, the crack number increases, and the average crack width decreases. During bending tests, the steel fiber-reinforced concrete segment shows remarkable characteristics of strain hardening and multiple cracking. The embedded parts reduce the cross-sectional area and cause stress concentration in the mid-span; therefore, the main crack form in this region.

Abstract: The production technology for automotive foundry castings has developed significantly during the past decade. The production of cylinder hats with more and more complex designs could be rather challenging for core makers. Heating might cause the annealing of the core, thus, the buoyancy of the molten metal increases which might cause the movement of the core. The heat distortion of the cores was examined with a Hot Distortion Tester. A universal Instron 5982 device was used for bending, wedge penetration strength and cold and hot compression tests. The test bars were prepared with cold- and hot-box processes using DMPA (Dimethylpropyl-amine) under laboratory conditions. The tests showed that the decrease of the bending strength is proportional to the amount of additives. The compression test results showed that the test bars produced with cold-box compression have the lowest and the ones with furan resin mixtures have the highest compressive strength.