A Numerical Stress-strain Response Model of All Grades of Concretes under Uniaxial Compression

摘要

An important problem facing stress-strain response modeling of concrete is the complexity of the compressive strength grades. 21 groups of specimens with different cubic compressive strength (56.3-164.9 MPa) have been numerically analyzed. Using only the compressive strength, a stress- strain response model of different concrete grade was established. The numerical simulation model not only quantitatively reproduces the relationship of uniaxial compressive strength, peak value stress and cubic compressive strength , but realizes the consistence of the ascending branch of stress-strain curves with different strength grades by introducing the correction coefficient k. The results indicate k increases gradually from 0 to approximate 1 with the increase of the compressive strength, corresponding to the transition from the paracurve to straight line branch in stress-strain curves. When k is 0, the model is identical to the Hognestad equation. A good agreement with the experiment data was obtained.