Fatigue and fracture mechanical properties of selected concrete for subtle precast structural elements

¹ Institute of Physics of Materials, ASCR, v. v. i., Zizkova 22, 616 62, Brno, Czech Republic
² Faculty of Civil Engineering, Brno University of Technology, Veveri 331/95, 602 00 Brno, Czech Republic
³ Faculty of Civil Engineering, VŠB Technical University of Ostrava, Ludvíka Podéště 1875/17, 708 33 Ostrava-Poruba Czech Republic

^* Corresponding author: seitl@ipm.cz, seitl.s@fce.vutbr.cz

Abstract

Precast concrete elements used as a civil structure are usually made of a cement-based matrix and natural aggregates (such as sand, gravel, crushed stone, etc.). These structures are usually exposed not only to a static load but also to a cyclic load if they load the bearing part of a bridge (traffic etc.). The knowledge of fatigue and fracture mechanical characteristics is important in designing and modelling new structures. This paper introduces and compares fracture mechanical properties obtained from static and fatigue tests for three kinds of concrete. The focus was set on the bulk density, flexural and compressive cube strength, fracture toughness and fatigue properties (S−N − Wöhler curve). All of these tests are important for a practical application in the design of precast concrete structures. The experimental results were statistically analysed and they showed that the fatigue and mechanical fracture properties improved with improved mechanical parameters of concrete.