Inverse Analysis of R-UHPFRC Beams to Determine the Flexural Response under Service Loading and at Ultimate Resistance

Bartłomiej Sawicki,Eugen Brühwiler,Emmanuel Denarié

doi:10.1061/(asce)st.1943-541x.0003239

Abstract

Ultra high performance fiber reinforced cementitious composites (UHPFRCs) have demonstrated their outstanding efficiency as structural materials. Determination of the bending resistance of members combining UHPFRC with steel reinforcement bars (R-UHPFRC) using material properties obtained by material testing gives satisfactory results. However, the synergetic interaction between rebar and UHPFRC in the tensile action due to bending, especially under loading–unloading of the structure is not yet well understood. This paper compared methods of analytical inverse analyses, as well as finite-element modeling and nondestructive testing (NDT), for determining UHPFRC material properties based on plates and R-UHPFRC members’ test results. It was demonstrated that UHPFRC in the tensile zone of R-UHPFRC members can enter into compression during unloading, influencing the structural response under service loading.

Highlights

Ultra high performance fiber reinforced cementitious composites (UHPFRCs) are a relatively new class of building materials (Naaman 2018)
Most of the research on stress distribution in R-UHPFRC members has focused on the ultimate resistance (Adel et al 2019; Farhat et al 2007; Habel et al 2007; Qiu et al 2020) or monotonic loading (Huang et al 2019; Yang et al 2019), without taking into account unloading of the member
Email: emmanuel.denarie@ epfl.ch of stiffness due to loading–unloading was discussed by Gao et al (2020), but without detailed analysis of stress distribution in the cross section or composite behavior between steel reinforcement bars and UHPFRC (Wang et al 2020)

Summary

Introduction

Ultra high performance fiber reinforced cementitious composites (UHPFRCs) are a relatively new class of building materials (Naaman 2018). Analytical and FEM inverse analysis methods were applied to determine material properties from bending tests of full-scale members and companion plate specimens.

Results

Conclusion