Experimental Investigation on Interfacial Defect Detection for SCCS with Different Contact NDT Technical

Abstract

Knowledge about air-incorporating additives in concrete can favor civil construction with structures that are lighter and more economical. This study investigated the production of concretes with the addition of 1 to 3% of air-entraining additive via the Micro-CT imaging technique. From the microtomography obtained, it was possible to obtain two-dimensional and three-dimensional images of the analyzed samples. The analysis of these images, using FEI Avizo 9.0 image processing software, allowed for obtaining the volumes of concrete, mortar, voids, and porosities of concrete mortars, in addition to the quantities, shapes, and dimensions of pores (voids) present in the samples. The air contents of the concrete with incorporated air were higher than the reference concrete, directly proportional to the additive contents used, and very close to the mixes with the same additive contents. Both the standard and modified mixes showed an increase in air content as the additive content increased. The specific mass of the concretes decreased as the additive content increased in the standard and modified concretes. As for consistency, the air-incorporated concretes showed greater slumps compared to the reference concrete and increased as the additive content increased, demonstrating the action of the air-incorporating additive in improving workability.

Keywords

• air entrained concrete
• Micro-CT
• concrete
• pores
• density