Title: Impulse Testing of Concrete Beams

Author(s): F. T. Mavis and F. A. Richards

Publication: Journal Proceedings

Volume: 52

Issue: 9

Appears on pages(s): 93-102

Keywords: no keywords

DOI: 10.14359/11589

Date: 9/1/1955

Abstract:
The purpose of this study was to find out whether reinforced concrete beams that are identical except for grade of reinforcement behave alike or differently under identical impulses; and if they behave differently, how much-and why? Structural-grade bars, and hard-grade bars that had heen rolled with identical deformations from a billet of rail steel, were obtained from the same manufacturer. Reams were cast in gang molds with structural-grade and hard-grade bars alternating in adjacent beams. After the preliminary tests, concrete was supplied by truck mixer in large enough quantities so there should be no question about uniformity of concrete in any one batch. A new testing machine was designed and built to apply identical impulses to two beams in any given test, and instruments and methods wrro devised to record what happened at, any instant during a test. Things that occured simultaneously were recorded photographically at a rate of 64 exposures a second; and charts were synchronized to shorn load-deflection-time data with comparable precision.