Test Method for Evaluating Bond Strength for 15.2 mm (0.6 in.) Diameter Prestressing Steel Strand, Grade 270, Uncoated, Used in Prestressed Ground Anchors

A wedged load test method is used to evaluate the adhesion strength of high-strength coatings, which have been processed with various sintering parameters. In this test, for stress concentration at cut tip, cracks are always induced and expanded rapidly cross the interface between coating and substrate. Macro-fracture and SEM image of coating interface of high-strength coating are characterized using optical microscope and scanning electron microscopy (SEM), respectively. In order to evaluate the bonding properties between coating and substrate effectively, corresponding finite element (FE) analysis has been conducted to evaluate the adhesion strength of high-strength coating. And stress distributions cross the interface of high-strength coating are obtained. The stress analysis can help to evaluate the bond strength of high-strength coating. Because of small specimen and contact relationship between wedged pressure head and wedged cuts, complex stress state is affected by many factors resulting from interface, and also by the thickness of coating.

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Wire Adhesion Testing

Rubber Chemistry and Technology ◽

10.5254/1.3544696 ◽

1972 ◽

Vol 45 (1) ◽

pp. 16-25 ◽

Cited By ~ 3

Author(s):

L. C. Coates ◽

C. Lauer

Keyword(s):

Bond Strength ◽

Physical Properties ◽

Test Method ◽

Material Strength ◽

Basic Design ◽

Rubber Compound ◽

Reliable Test ◽

Adhesion Testing ◽

Rubber Compounds ◽

The Relationship

Abstract The results of this study are conclusive. The ASTM D-2229 Test Method is not a reliable test for measuring adhesion of wire cords to rubber compounds. However, by using the basic design and modifying it, an accurate measurement of bond strength on a macroscopic level can be obtained. This test is insensitive for all practical purposes to compound physical properties and changes in cord diameter and embedded length—for both stranded and rod-like cords. It is also possible with this test to calculate the amount of stress that is exerted on the surface of the wire cord to determine the relationship between failing stress and the material strength of the rubber compound. Properly used, this new test should give the compounder a better tool to study the adhesion of compounds to metal.

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Experiment Study on Interfacial Normal Bond Strength of Concrete Filled Steel Tube

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.947 ◽

2012 ◽

Vol 594-597 ◽

pp. 947-954 ◽

Cited By ~ 3

Author(s):

Zhen Yu Liu

Keyword(s):

Bond Strength ◽

Temperature Change ◽

Concrete Strength ◽

Steel Tube ◽

Test Method ◽

Bending Test ◽

Concrete Filled Steel Tube ◽

Normal Bond ◽

Core Concrete ◽

Test Result

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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