Title: Cracked Continuum Modeling of Reinforced Concrete Elements under Impact
Author(s): Serhan Guner, Trevor D. Hrynyk, and Andac Lulec
Publication: Symposium Paper
Appears on pages(s): 85-105
Keywords: axisymmetric, erosion, frame, missile, perforation, shear, shell, smeared, solid, strain rates
Current computational modeling approaches used to evaluate the impact-resisting performance of
reinforced concrete infrastructure generally consist of high-fidelity modeling techniques which are expensive in terms
of both model preparation and computation cost; thus, their application to real-word structural engineering problems
remains limited. Further, modeling shear, erosion, and perforation effects presents as a significant challenge, even
when using expensive high-fidelity computational techniques. To address these challenges, a simplified nonlinear
modeling methodology has been developed. This paper focuses on this simplified methodology which employs a
smeared-crack continuum material model based on the constitutive formulations of the Disturbed Stress Field Model.
The smeared-crack model has the benefit of simplifying the modeling process and reducing the computational cost.
The total-load, secant-stiffness formulation provides well-converging and numerically stable solutions even in the
heavily damaged stages of the responses. The methodology uses an explicit time-step integration method and
incorporates the effects of high strain rates in the behavioral modeling of the constituent materials. Structural damping
is primarily incorporated by way of nonlinear concrete and reinforcement hysteresis models and significant secondorder
mechanisms are considered. The objective of this paper is to present a consistent reinforced concrete modeling
methodology within the context of four structural modeling procedures employing different element types (e.g., 2D
frames, 3D thick-shells, 3D solids, and 2D axisymmetric elements). The theoretical approach common to all
procedures and unique aspects and capabilities of each procedure are discussed. The application and verification of
each procedure for modeling different types of large-scale specimens, subjected to multiple impacts with contact
velocities ranging from 8 m/s (26.2 ft/s) to 144 m/s (472 ft/s), and impacting masses ranging from 35 kg (77.2 lb) to
600 kg (1323 lb), are presented to examine their accuracy, reliability, and practicality.