Ring test for evaluation of bond properties of reinforcing bars

ABSTRACT A pull-out bond test with short bond length for estimation of the splitting tendency of different rib shapes for reinforcing bars is proposed and investigated. In the test the bond force component along the bar is separated from the radial one. The radial component is determined by measuring circumferential strain in a steel ring surrounding the concrete of the pull-out specimen. The force component, which is longitudinal to the bar, is obtained by supporting the pull-out specimen with a teflon covered circular support close to the bar. Bars with specially turned ribs are studied concerning rib height and rib distance. Swedish standard high bond bars are also studied. The splitting tendency is stated as a function of the slip of the free bar end and also of the related rib area of the bars

Building Materials in the Light of Physics of Matter

AbstractThis paper outlines an approach for joining physics of matter with the knowledge in building materials when teaching students in civil engineering. Students at most universities are schooled in physics and then building materials in separate courses, but nobody teaches them how to join both fields of science in a fruitful understanding. The described method of evaluating material properties and performances facilitates the understanding and judgment of how and what can be done to change and improve materials. The method is here related to iron and steel with special aim to understand the properties of amorphous steel, but can easily be used to understand for instance high performance concrete, wood or other materials