Functionally Graded Concrete for The Civil Infrastructure - A Multifunctional Material System Approach

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

This project develops novel multifunctional and functionally graded concrete materials (FGCMs) for the civil infrastructure. FGCMs consist of multiple sub-regions within a structural layer with varying concrete constituents following a predefined compositional function, e.g. functionally graded fiber-reinforced concrete slab with varying through-thickness toughness. A multi-scale testing (including small-scale specimen fracture tests and large-scale tests of concrete slabs), modeling, and education plan will be undertaken to achieve the project goals. The integrated modeling will be accomplished by distinct constitutive descriptions for the bulk (with special graded finite elements) and the ?separation? (cracked) materials through and a tailored cohesive zone model approach able to capture material degradation and material gradient effects at the mesoscale. A virtual internal bond (VIB) model will also be formulated using a continuum approach for strain localization employing a new pair-bond potential concept. A comprehensive educational plan is clearly essential to the success of this project since teaching of students (in-reach) and practicing engineers (out-reach) are needed to implement the multi-scale FGCM testing and fracture modeling program. The integrated research and education plan is expected to have a broad impact on the following areas: infrastructure materials research, civil engineering student education through development of an integrated design course at UIUC on ?Engineering Functionally Graded Concrete Materials for the Infrastructure,? interaction with practicing engineers through development of technology transfer activities (e.g. short courses), research experience and mentoring for undergraduate students and graduate research assistants, and summer mentoring and research experience for underrepresented students.