Compression Bending Test Method for Advanced Composites.

To study the debonding of concrete filled steel tube (CFST), pulling and bending methods were used to test the normal bond strength. Based on the test result, debonding due to temperature change and shrinkage of core concrete in CFST was analyzed. The test and analysis result shows that the bending method is a better test method; the concrete strength has little influence on bond strength while the surface condition of steel has much influence on it. The bond strength of steel which is rust is greater than that of the steel with smooth surface. According to the analysis on the bending test result, the normal bond strength of 0.86MPa was got and the debonding of CFST arch was analyzed, the analysis result shows that debonding will easily happen under the action of temperature change and shrinkage of core concrete. The test methods and results can provide a reference for engineering applications.

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Study on the Creep Properties of Resin Concrete

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.472.649 ◽

2014 ◽

Vol 472 ◽

pp. 649-653

Author(s):

Hui Cun Shen ◽

Kui Tian ◽

Yan Hua Hu

Keyword(s):

Dynamic Stiffness ◽

Structure Design ◽

Test Method ◽

Bending Test ◽

Creep Properties ◽

Four Point Bending ◽

Long Term Effect ◽

Urgent Task ◽

Machined Parts ◽

New Material

Resin concrete is a new material which can be made into machine bed instead of the traditional pieces of gray cast iron as the machine base, it can improve the dynamic stiffness of machine tools and the quality of machined parts, and extend the campaign life, reduce noise and improve efficiency. However, due to the long-term effect of load of the resin concrete, the elastic deformation occurs in its component, and the strain will increase over time. Thus it can affect the resin concretes service life, and the calculation of creep has become an urgent task in structure design and use, which should be taken seriously. In this paper, the bending creep properties of resin concrete beam were studied and analyzed by using four-point bending test method. The creep curve under different load levels were obtained, and the viscoelastic properties were analyzed.

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Comparative Study on the Test Method for Tensile Elastic Modulus of Rock Materials

Advances in Civil Engineering ◽

10.1155/2019/3161953 ◽

2019 ◽

Vol 2019 ◽

pp. 1-18

Author(s):

Yan Zhang ◽

Dawei Yu

Keyword(s):

Elastic Modulus ◽

Comparative Investigation ◽

Test Method ◽

Bending Test ◽

Brazilian Disc ◽

Rock Materials ◽

Brazilian Disc Test ◽

Test Operation ◽

Uniaxial Compressive Test ◽

Tensile Elastic Modulus

Rock material has different mechanical behaviors under compressive and tensile loading. Correspondingly, there are two types of elastic modulus: compressive elastic modulus Ec and tensile elastic modulus Et, respectively. To distinguish which indirect test methodology, including three-points bending test and Brazilian disc test, is more suitable to measure the tensile elastic modulus Et of rock materials, a series of uniaxial compressive test (UCT), direct tensile test (DTT), three-points bending test, and Brazilian disc test are performed for three typical types of rock: marble, granite, and sandstone. Comparative investigation on the reliability of measurement results of tensile elastic modulus Et is systematically conducted. Finally, it is found that Brazilian disc test could be a suitable method to measure tensile elastic modulus of rock materials, due to the excellent agreement with that measured by DTT and the simplicity of sample preparation, as well as test operation.

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Characterization of the Constitutive Behavior of a Cathode Active Layer in Lithium-Ion Batteries Using a Bending Test Method

Experimental Mechanics ◽

10.1007/s11340-020-00613-5 ◽

2020 ◽

Vol 60 (6) ◽

pp. 847-860 ◽

Cited By ~ 1

Author(s):

P. Gupta ◽

İ. B. Üçel ◽

P. Gudmundson ◽

E. Olsson

Keyword(s):

Lithium Ion Batteries ◽

Active Layer ◽

Lithium Ion ◽

Test Method ◽

Bending Test ◽

Constitutive Behavior

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Investigation of Interlaminar Defects and their Influence on Interlaminar Strength

Advanced Composites Letters ◽

10.1177/096369359600500404 ◽

1996 ◽

Vol 5 (4) ◽

pp. 096369359600500

Author(s):

J Ziao ◽

J Tao

Keyword(s):

Tensile Strength ◽

Large Scale ◽

Peel Strength ◽

Test Method ◽

Bending Test ◽

Four Point Bending ◽

Transverse Tensile ◽

Interlaminar Shear ◽

Transverse Tensile Strength ◽

Set Up

In this paper, we directed our attention to the interlaminar defects and their influence on the interlaminar strengths. With the aid of a S-570 scanning electron microscope, the morphology and distribution of interlaminar defects were inspected and documented. According to their shape, size and cause of formation, the defects were classified into five types: flakiness void, irregular shaped debond, local imperfectly cured resin, debond in two multi-directional plies, and inhomogeneous fibers and the large scale debond by these fibers. The cause of defects formation was discussed by analyzing the manufacturing process of composites. The influence of defects on the interlaminar strength and its mechanism was analyzed experimentally and theoretically. The results indicate that these defects, with different effects, decrease the interlaminar strength because they form interlaminar cracks, and the interlaminar shear strength is less affected than interlaminar tensile strength, which is measured according to GB4944 test method. To comprehend defects distribution effect, a four-point-bending test method was introduced to measure the interlaminar peel strength, and a discussion was made on the correlation between the interlaminar tensile strength, interlaminar peel strength and in-plane transverse tensile strength. Finally the concept of interlaminar defect coefficient, which can be used to characterize the defects, was set up and the formula to calculate it was proposed.

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Sensitivity Analysis of Semi-Circular Bending Test using Plackett–Burman Matrix

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198120907587 ◽

2020 ◽

Vol 2674 (2) ◽

pp. 302-312

Author(s):

Shadi Saadeh ◽

Yazan Al-Zubi ◽

Enad Mahmoud ◽

David Renteria ◽

Louay Mohammad

Keyword(s):

Test Method ◽

Bending Test ◽

Test Results ◽

Notch Depth ◽

Air Voids ◽

Scb Test ◽

Negative Effect ◽

American Society ◽

Set Up ◽

Positive Effect

The semi-circular bending (SCB) test is a recently developed test method, adopted by the American Society of Testing and Material (ASTM) as ASTM D8044, to evaluate the cracking resistance of asphalt mixtures. To measure the robustness of the SCB test, a ruggedness test is needed. In this study, the effect of small changes in the key parameters of the test method on the results of the test were numerically investigated. The test method has many variables and set up conditions. Examining all of these parameters would be cumbersome using traditional testing and statistical techniques, as they require a significantly high number of samples. The Plackett–Burman (PB) technique was used to conduct the ruggedness test while reducing the number of tests required. Seven parameters have been examined: notch location, notch depth (low, intermediate and high), air voids, loading rate, and span length. Even using the PB technique, 16 scenarios need to be tested, and each scenario requires three specimens, one for each of the three notch depths. Hence the process requires plenty of time and material. In this study, the SCB test was modeled using a discrete element method (DEM) approach to analyze the fracture behavior of the samples. DEM was used to develop a model that reduced the time and materials required for the SCB test. Results showed that the parameters with most positive effect were intermediate notch depth and notch location, while those with the most negative effect were loading rates and air voids.

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