Average reinforcement strain in reinforced concrete structures

Abstract

Reinforced concrete’s versatility and strong structural performance make it one of the most prevalent materials used in civil engineering. The effects of impulse loads on reinforced concrete structures and the structural response that follows is of ever-growing interest amongst engineers. The purpose of this thesis is to better understand the impacts of altered parameters on the average strain in reinforced concrete prisms subjected to tensile loading. This average strain is of importance as it is correlated to the structure’s plastic deformation- and energy absorption capacity. Experiments were conducted on reinforced concrete prisms in which the prisms were subjected to static tensile loading until failure. Varying reinforcement diameters along with segments of PVC tubing around the steel reinforcement were implemented in prisms resulting in varying average strains. Digital Image Correlation (DIC) was used to analyze and document the testing and subsequent responses. Strain fields, crack widths, and total displacement for each prism were studied using the processed DIC data and then plotted using Microsoft Excel. Plastic deformation capacities were predicted to be higher amongst prisms with PVC due to the advantageous decrease in bond between the materials. Interpretation of the results, however, showed an inverse effect from the PVC tubing, i.e. lower strain values and total displacements. However, these results are difficult to apply to the study of full-scale beams as this thesis was limited to reinforced concrete prisms. Beams, with a more complex steel reinforcement configuration, may be influenced more by the PVC tubing resulting in higher average strain values. Further research on this subject is desired as protective concrete structures are of great interest amongst public agencies and engineers in the civil engineering field.