A continuum damage theory for cyclic loading of concrete
Date of Award
Doctor of Philosophy (Ph.D.)
Civil and Architectural Engineering
First Committee Member
Wimal Suaris, Committee Chair
A continuum damage theory for the monotonic and cyclic behavior of concrete is developed and its validity is verified experimentally. The microcracking that occurs during loading is modelled by using a second order tensorial damage variable which is capable of modeling non-planar cracks which usually occur in concrete under uniaxial compression. The strain-energy release-rate due to crack growth obtained from the present theory complies with classical fracture mechanics results. Damage evolution is obtained using a scalar valued loading surface and bounding surface which are defined in terms of the thermodynamic force conjugates of the damage variables. A series of uniaxial compression and cyclic loading tests were conducted with stress/strain measurements. The damage growth during the tests were monitored by transmitting and receiving ultrasonic waveforms along axes perpendicular to the applied compressive stress. The damage growth was inferred from the amplitude-attenuation of the received waveform which was found to be a more sensitive indicator than the more widely used pulse velocity technique. The small difference in theoretically predicted curves and experimentally determined curves may be attributed to the plastic deformations. The ratio of compressive/tensile strength, damage growth rate curves and S-N curves for cyclic loading were found to be predicted well by the proposed theory.
Fernando, Viraj M., "A continuum damage theory for cyclic loading of concrete" (1987). Dissertations from ProQuest. 2637.