Estudo comparativo de pontes de aderência para recuperação de estruturas em concreto

Abstract

The efficiency of the products with the role of adherence bridge is still very debated in the civil construction sector when it comes to the process of structural repair of the concrete. It is possible to say that there is negligence regarding the material selection study when it comes to adherence bridges applications. Considering the actual circumstances, it is essential to enhance and enrich the knowledge about such materials. The objective of the present study is to establish performance comparisons between two types of adherence bridges (epoxy and mineral), as well to measure the bonding capacity of two kinds of structural repair mortars both in the presence and absence of adherence bridges. The methodology consists of making axial compression tests in samples made of two combinations of materials (concrete substrate and structural repair mortar with and without adherence bridges being applied on the interface). Due to making a sloping interface with the angle of 45 degrees between the concrete substrate and the repair material (mortar and bridge), when charging the sample with an axial force, a rupture tension directly related to the bonding capacity between the materials appears. To produce the substrate, two kinds of concrete were used (conventional and self-compacting concrete) and also two types of mechanical treatments, what made possible different levels of adherence between the concrete and the repair material. It was possible to notice that the adherence bridges applied separately or already included in the structural repair mortar did not contribute directly to the bonding performance between the materials. It was also noticed that the mechanical treatment applied to the concrete surface affects directly the bonding capacity between the materials, since the samples which surface didn’t receive a mechanical treatment (abrasion) presented bigger frequency of oblique shear ruptures, providing the detachment between the concrete substrate and the repair material.