Study of mixed beams of wood and concrete with rubber waste for use in bridges

Abstract

An appropriate dosage of added rubber particles in wood-concrete bridge beams would allow a proper final destination for wasted tires. Besides, impact absorption provided by added rubber in this type of structure improves their behavior regarding dynamic loads. This project aims to analyze the behavior of wood-concrete bridge beams by means of flexural strength tests. Eight wood-concrete beams will be tested in this study. These beams will be provided with steel bars set to "X", which allow the connection between wood and concrete, while in the high resistance connection is maintained. This type of connection reduces the wood-concrete beams manufacturing costs. Two tests will be performed with no added rubber particles specimens in order to be used as reference tests. The other wood-concrete beams will be prepared with different rubber percentages (5-15%, in volume). Firstly, wood-concrete beams will be submitted to nondestructive flexural tests to determine its maximum vertical displacement and the corresponding stress. Afterwards, destructive flexural tests will be performed with the same specimens to define their strength related to this type of load. These results will be used to compare the stress strain behavior of the wood-concrete beams. In addition, numerical analyses will be conducted in order to verify the stress-strain distribution in this type of structure. (AU)