Calibration of ABAQUS Concrete Damage Plasticity (CDP) Model for UHPC Material

Ultra-high performance fiber reinforced concrete (UHPFRC) is an advanced cementitious material with exceptional mechanical properties including, a compressive strength in the range of 120 to 200 MPa, a tensile strength up to 15 MPa with a hardening post-peak behavior, significant durability, and ductility. Due to their speed, affordability, and versatility in providing numerous results options, finite element (FE) simulations can be used to analyze various structural systems under different loads (e.g., mechanical, thermal, coupled field). Of the commercially available software, ABAQUS has been widely used to simulate the behavior of concrete members. The concrete damage plasticity (CDP) model is the flagship and only constitutive model in ABAQUS applicable for representing the brittle nature, cracking, and crushing failure in concrete-like materials. As the model inputs have been exclusively developed and calibrated for conventional concrete, they might not be applicable to UHPC. Particularly the model inputs related to shear and tension behaviors might differ between conventional concrete and UHPC, where aggregates present in the former provide shear mechanical interlock, lacking in the latter, while fibers in the latter provide tensile bridging effects, lacking in the former. This study aims to calibrate the various parameters of CDP model, including the dilation angle, eccentricity, stress ratio, stress-strain curve for tension and compression, for UHPC, using a large database of experimental results. Recommended values and ranges are provided in the manuscript to enable accurate analysis of UHPC members in ABAQUS.