Compressive strength of concrete in test specimens and structures

The research project aims to:

• Uncover how different variables in concrete cores affect the compressive strength of concrete, and

Improve our understanding of the behaviour of air-entrained concrete in bending.

There are certain situations where the compressive strength of concrete must be determined based on an existing structure. In this case, the most reliable estimate for compressive strength is obtained from concrete cores. The variation of several different properties is characteristic of concrete cores. The effects of these variables on the compressive strength of test specimens representing current Finnish concrete types have not been studied before. This project seeks to determine the relation between the compressive strengths of different-sized concrete cores and the compressive strengths of standard specimens. The project will also improve or understanding of how the strength of test specimens is affected by their moisture condition and end preparation method as well as the condition of the diamond core drill bit. A further objective is to examine the response of air-entrained concrete to short-term and long-term bending stresses. We will also compare the compressive strength of concrete cores and concrete strength in bending. The results of this project can be utilised in future standardisation work.

The research project builds on the results of a preliminary study published in the Finnish Transport Agencys publication series (http://urn.fi/URN:978-952-317-555-6). The first stage of the project explores the effects of different properties of concrete cores on compressive strength. We will manufacture and test more than a thousand specimens of varying sizes and grades of concrete.  During the second stage, we will manufacture several reinforced concrete beams. The specimens of varying air content will be tested under different loading rates to shed light on the behaviour of concrete in bending.

Project manager Jukka Haavisto    

jukka.haavisto [at] tut.fi    

040 198 1885