Open AccessCOMPREHENSIVE STUDY OF THE PROPERTIES OF FINE-GRAINED CONCRETE UNDER DYNAMIC TENSION AND SHEAR
Author(s) -
Mikhail E. Gonov
Publication year - 2020
Publication title -
problemy pročnosti i plastičnosti
Language(s) - English
Resource type - Journals
ISSN - 1814-9146
DOI - 10.32326/1814-9146-2020-82-4-442-457
Subject(s) - materials science , ultimate tensile strength , shearing (physics) , split hopkinson pressure bar , dynamic tension , composite material , shear (geology) , deformation (meteorology) , direct shear test , structural engineering , rod , dynamic testing , tension (geology) , strain rate , engineering , medicine , alternative medicine , pathology
An experimental study of the dynamic properties of fine-grained concrete under tensile and shear stresses has been carried out. A comprehensive study of the dynamic properties of concrete allows obtaining experimental data and constants. These data and constants are needed to equip dynamic strain and fracture models. The system of experiments is based on modifications of the Kolsky method. This system of experiments allows one to determine a wide range of strength and time characteristics of concrete under shock loading. The experimental setup according to the Kolsky method includes a system of measuring rods between which a test sample is installed, a gas gun for accelerating a cylindrical striker, strain gauges, a speed meter, recording and computing equipment with a software package. Conducted dynamic tests of concrete in a wide range of deformation rates (102–104 s–1). In experiments on direct tension and to determine the ultimate tensile stress of fine-grained concrete during splitting, two speed modes are implemented. In tests of shear strength, a modification of the Hopkinson split bar method was used to determine the dynamic shear strength, in which a sample made of the material under study is located in a rigid holder cut at an angle to the sample axis. The pulse recorded in the reference dipstick is used to plot the shear stress in the sample over time. Shear tests were carried out for three speeds. The results of the performed experiments on tensile, splitting and shearing are presented in the form of diagrams of stress versus deformation and stress versus time. The obtained characteristics can be used to equip computational experiments in the study of the strength of concrete structures subjected to dynamic influences.