A Direct Tensile Strength Testing Method for Concrete from Existing Structures

Abstract

Tensile strength is a crucial property for the function, safety and durability of all concrete structures. The general procedure to assess the tensile properties of concrete from existing structures is to perform indirect tests and predict the tensile strength based on established empirical relationships. In this study, the direct tensile strength of concrete was investigated using cylindrical specimens. The aim of the study was to propose, test and evaluate a general method for direct tensile tests of concrete from existing structures. A total of 16 specimens were tested under deformation-controlled tensile-loading until failure. The concrete samples were prepared with 10 or 15 mm grooves at mid-height to obtain cracking in the groove region, where the crack-opening sensors were installed. The load and corresponding deformation were recorded continuously during the test to obtain the load–crack-width relationship of the concrete. The tests showed that the method can be used to assess the tensile properties of concrete from existing structures. The study provides important insights regarding the assessment of direct tensile strength of concrete and the results can be used to improve the structural health monitoring of existing structures and thereby ensure their safety and durability.