The Modified Compression-Field Theory for Reinforced
Concrete Elements Subjected to Shear
Frank J. Vecchio and Michael P. Collins
Appears on pages(s):
aggregate interlock; axial loads; biaxial loads; cracking (fracturing); crack width and spacing; finite element method; offshore structures; reinforced concrete; shear strength; stiffness; stresses;stress-strain relationships; structural analysis;tension.
An analytical model is presented that is capable of predicting the load-deformation response of reinforced concrete elements subjected to in-plane shear and normal stresses. In the model, cracked concrete is treated as a new material with its own sttress-strain characteristics. Equilibrium, compatablity, and stress-strain relationships are formulated in terms of average stresses and average strains. Consideration is also given to local stress conditions at crack locations. The stress-strain relationships for the concrete were determined by testing 30 reinforced concrete panels under a variety of well-defined uniform biaxial stresses including pure shear. It was found that cracked concrete subjected to high tensile strains in the direction normal to the compression is softer and weaker in compression than conrete in a standard cylinder test. Additionally, significant tensile stresses were found in the concrete between the cracks even at very high values of average tensile strain.