Abstract
The main objective of this research was the charac terisation of the fracture toughness of concrete mortars exposed to high temperatures by using notched specimens in three point bending tests. The specimens have different lengths and were heated at different temperatures ranging from room temperature up to 900°C. The experimental test results obtained are closed with those reported by the literature, it shows tha t beyond approximately 300°C, the fracture loads decrease strongly with the rise in heating temperat ure. However, between the room temperature (25°C) and 300°C, we recorded an increase of the fr acture load. Two methods using the experimental critical load were applied to calculat e the fracture toughness of concrete mortars: an analytical method based on the mechanics of continu ous medium theory and a numerical approach using finite elements method. The numerical modelli ng has then been validated, discussed and compared with analytical solution. Comparison between the experimental results and the theory predictions was quite good.
Highlights
The elastic linear mechanics of fracture (MLER) is a usual theory for analysing the fracture of metals or brittle materials such as glass or ceramics[1]
The fracture load decreases with the rise in heating temperature
In order to push of advantage the study on the behaviour of these concrete mortars exposed to elevated temperature, we were interested in the characterization of their toughness in opening mode
Summary
The elastic linear mechanics of fracture (MLER) is a usual theory for analysing the fracture of metals or brittle materials such as glass or ceramics[1]. Concrete is a composite material, its mechanical performance did not reflect the simple theory of composites The non-linear (inelastic) behaviour of concrete under stress can be explained by defining concrete as a three phase heterogeneous material, the cement paste, the aggregates and the transition zone (TZ). Because of its high porosity and low strength, microcracks can propagate in the transition zone while the other two phases are not Cracked. This result is the non-linear behaviour of the concrete composite. While the ascending part of the concrete stress-strain curve is only dependent on cracking extent in concrete, the descending part is highly influenced by the testing machine characteristics especially its stiffness
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.