Title: Experimental Results of Fracture Energy and Brittleness Numer for High-Performance Concrete Specified in Brazil

Author(s): V.S. Caland, M.S.L. Velasco, and R.A. Einsfeld

Publication: Symposium Paper

Volume: 207

Issue:

Appears on pages(s): 361-380

Keywords: experimental analysis; fracture mechanics; high-performance concrete

DOI: 10.14359/12401

Date: 10/7/2002

Abstract:
In this work, some experimental results for determination of fracture energy and brittleness number for high-performance concrete are presented. Three-point bend tests were conducted for different concrete mixture proportions, with compressive strengths of 70 MPa to 90 Mpa. The tests were performed using crack mouth opening displacement control in a closed-loop servo-hydraulic system. The experiments involved the testing of 75 single-notched beams of four different sizes in order to study the size effect. The compositions of the concrete were established according to, those specified by IBRACON (Brazilian Concrete Institute) in order to match the concrete commonly used by companies that operate in Brazil. The results found in this work by the method proposed by RILEM show that the size of the specimens influences the value of the obtained fracture energy, it being larger as the size of influences the value of the obtained fracture energy, it being larger as the size of the specimen increases, thus suggesting that the RILEM method is not valid in characterizing fracture energy as a material parameter. The results from this work found that the fracture energy obtained by the method proposed by Bazant and Pfeiffer can be adopted as a fracture parameter of the material, since its value is independent of the size of the specimen.