Investigation of concrete and reinforced concrete members having different section sizes under impact effect

Structural members are exposed to several loading cases and environment conditions during their economic lives. Behavior pattern of structural members under various loads have become more prominent with the advancing technology. Effect properties as time and instantaneous intensity that may reach very high values under impact loading which is a sudden dynamic one are not completely definite. It is stated by scientists and engineers that impact effect on solids shall not be ignored due to terrorist attacks and destructive earthquakes in recent years. For this reason, determination of structural members' properties under dynamic effects as sudden winds, earthquakes, vehicle accidents, missile and projectile crashing has become an important research subject. Number of studies gradually increases to determine the behavior of structural members under impact effect by using drop weight testing apparatuses according to free falling movement. In this thesis study, 6 concrete and 6 reinforced concrete members whose sizes differ from 100x100x710 to 200x200x710 mm are produced. These 12 test members are investigated under impact effect by designed testing apparatus. While weight of the hammer is 8 kg, drop height is taken as 1000 mm. There are 4 accelerometers, 1 force sensor, 1 data logger, 1 computer and connection wires used in tests as well as steel plate and rubber layer to distribute the impact force on test members and reduce the inner effects at impact moment. Drop times are measured by optic photocells which are placed in the testing apparatus. Damage situations of test members having different section sizes are determined and acceleration-time, velocity-time, displacement-time, impact force-time and impact force-displacement graphs are created. In addition, absorbed energy values by test members are calculated. Drop numbers causing damage situations and total drop numbers are read from the electronic screen which is also placed in the apparatus. Besides that, rebound numbers and time intervals are determined for each member. In finite elements analysis part which is performed after completing the experimental study, testing apparatus and test members are modeled by ABAQUS finite elements analysis program. After defining the material properties and support conditions, test members are analyzed under impact effect. Stress distributions are obtained for the first drop movement of the hammer. Finally, graphs and energy absorption capacities which are obtained by finite elements analysis are compared with the test results and suggestions are proposed. Keywords: ABAQUS, concrete and reinforced concrete test members, impact effect, testing apparatus, different section sizes, finite elements analysis