Method for the Improvement of the Elasticity Module of Concrete Specimens by Active Confinement

The purpose of this work is to improve the modulus of elasticity of reinforced concrete pillars in the area where it is known with certainty that the concrete is elastic. To achieve this, an innovative method was devised to introduce an initial tension ( σ i ) resulting in an 11% increase in the working compression. Three concrete batches of five specimens each were prepared for this study. The first batch was used as a control without applying any reinforcement, the second was reinforced with a carbon fiber fabric (CF) layer in the usual way, and in the third batch, an initial tension was introduced to the CF fabric by a technique devised for this purpose. After measuring the modulus of elasticity of each of the specimens that made up each batch, it was observed that the modulus of elasticity obtained for the specimens in the third batch was 8% higher than the specimens in the first and second batches. The compression–deformation behaviour of the specimens observed throughout the study allows us to propose a stress–strain model with three different behaviours: linear elastic, parabolic elasto-plastic and linear elastic.