Finite element modeling of bond-slip relationship: Constitutive modeling and computational aspects.

摘要

This dissertation addresses the problem of finite element modeling of the bond-slip relationship between deformed reinforcing steel and the surrounding concrete. The bond mechanism is known to be influenced by many parameters, such as lateral confinement, the yielding of the reinforcing steel bar and the relative slip between steel and concrete. However, it is common to assume that the bond stress is solely dependent on the relative slip between the reinforcing bar and the concrete in finite element modeling of reinforced concrete structures. A new approach is developed here aimed at adjusting the bond strength dynamically in this research within the framework of an embedded reinforcement approach.; Research efforts have been focused on accurate constitutive modeling of these different materials---concrete, steel and bond-slip, and their integration into an object-oriented finite element program, Structural Analysis Utility for Civil Engineers (SAUCE). It is important to note that conforming to the mechanics of the problem and improving computational efficiency of solution are two major priorities of the constitutive modeling. Material models have been verified with experimental data and satisfactory agreement has been reached. SAUCE is developed as a case study of the formal software engineering approach and tested in different levels. SAUCE results are seen to match well with experimental results in numerical examples.