PRACTICAL METHOD OF CONDUCTING THE INDIRECT TENSILE TEST

Abstract

A PRACTICAL METHOD OF CONDUCTING THE INDIRECT TENSILE TEST TO DETERMINE THE TENSILE PROPERTIES OF STABILIZED MATERIALS IS DESCRIBED. A PAIR OF HALF-INCH-WIDE CURVED FACE LOADING STRIPS AND LOADING EQUIPMENT CAPABLE OF APPLYING A COM- PRESSIVE LOAD AT A CONTROLLED DEFORMATION RATE, PREFERABLY 2 INCHES PER MINUTE, MUST BE USED TO DETERMINE TENSILE STRENGTH. THE LARGE MOTORIZED GYRATORY PRESS IN USE BY THE TEXAS HIGHWAY DEPARTMENT CAN PROVIDE THIS LOADING RATE AND CAN BE EASILY MODIFIED TO ACCEPT THE LOADING STRIPS. FROM THE DIMENSIONS OF THE TEST SPECIMEN AND FAILURE LOAD, THE TENSIL STRENGTH CAN BE CALCULATED. THE DETERMINATION OF POISSON'S RATIO, THE MODULUS OF ELASTICITY, AND THE TENSILE STRAINS REQUIRES THE MEASUREMENT OF VERTICAL AND HORIZONTAL DEFORMATIONS OF THE SPECIMEN AT VARIOUS APPLIED LOADS. SIMPLE MATHEMATICAL EQUATIONS HAVE BEEN DEVELOPED TO CALCULATE THESE TENSILE PROPERTIES. /FHWA/