Fatigue of Plain Concrete Subjected to Biaxial-Cyclical Loading concrete; stresses; tension.
Leonard A. Traina and Abdulmajeed A. Jeragh
Appears on pages(s):
biaxial loads; cubes; cyclic loads; deformation;
fatigue (materials); fatigue tests;plain concrete; stresses;
stress-strain relationships; volume change.
The objective of this investigation was to study ex-perimentally the behavior of plain concrete subjected to slow cyclical loading in compressive uniaxial and biaxial states of stress. A triaxial testing machine which had been successfully used to study the response of plain concrete cubicai specimens subjected to static multiaxial stress states was used in this study. The test specimens were subjected to prescribed stress histories which included 15 maximum stress levels. In addition to the uniaxial state of stress, biaxial stress states of two types were studied. The first was a proportional loading type in which two loading paths were used, namely 02/q = I .O and 02/01 = 0.5. The second loading type consisted of a constant stressing the direction with a cyclical loading in the 01 direction. The cyclical loading ranged from zero to various percentages of the unconfined static strength of the cube. Cycle rates used were in the range of one- cycle per minute. Strain measurements in all three principal directions were recorded for each test. This data was used to show the effects of number of cycles, load paths, and state of stress on the dilatational, as well as stress-strain response for plain concrete. The data waslso used to show the effect of state of stress and load path on the fatigue strength of concrete.