Date of Completion
Ultra-high performance concrete (UHPC) has been developed in recent decades as a new class of concrete which exhibits increased strength, durability and long-term stability when compared with normal strength concrete (NSC) and high performance concrete (HPC). While extensive research has previously been performed on constitutive modeling of NSC, constitutive modeling of HPC and UHPC is very limited and more research needs to be pursued in this area. Robust constitutive modeling will allow for accurate and reliable modeling and simulation of UHPC structures which is needed for their analysis and design.
In this thesis, three elastic-plastic and damage models that were previously used to predict the mechanical properties of NSC were evaluated for use with HPC and UHPC. The models evaluated were the Concrete Smeared Crack (CSC) model and Concrete Damage Plasticity (CDP) model in ABAQUS, and the Continuous Surface Cap Model (CSCM) in LS-DYNA. ABAQUS and LS-DYNA are two widely used finite element analysis (FEA) codes. The constitutive models were calibrated using laboratory data from three different materials: two types of HPCs without fibers with compression strengths of 70MPa and 100MPa, and one UHPC with fibers with compression strength of 170MPa. The material parameters in the constitutive models were optimized for HPC and UHPC by fitting uniaxial and triaxial compression test data.
It is shown that all three constitutive models with optimized parameters reasonably fit the test data but addition testing is desirable to further generalize the results. Additionally, the optimized results indicate that the material parameters of UHPC are significantly different from NSC and HPC due to the presence of fiber.
Li, Jingcheng, "Evaluation of Elastic-Plastic and Damage Models for Ultra High Performance Concrete (UHPC)" (2011). Master's Theses. Paper 185.