Dynamic triaxial compression experiments on Cor-Tuf specimens

A set of dynamic triaxial compression experiments at 50 MPa, 100 MPa, and 200 MPa confinement have been conducted with a modified Kolsky bar on cylindrical ultra high strength concrete Cor-Tuf specimens of diameter 19 mm and length of 12.7 mm. The experiment is composed of a hydrostatic phase which occurs at a quasi-static strain rate followed by a dynamic shear phase which occurs at a high strain rate. A set of 28 experiments were conducted at strain rates of 100 s−1 and 200 s−1. The experiments show that the fracture strength of the material increases under the test conditions. The specimens showed higher strength in the dynamic confined experiments than both the quasi-static TXC tests and the unconfined dynamic tests. The strength increase was attributed to specimen size difference and not a strain rate or confinement effect. Although the trend towards brittle ductile transition is observed the specimens were not tested in a high enough confinement for the phase change to occur.