Revision and development of material models of ultra-high performance concrete containing coarse aggregate and applications in structural-level flexural response predictions

Abstract

Ultra-high performance concrete recently has attained immense attention in the construction industry for its superior mechanical characteristics. Nevertheless, its application remains restricted by its high cost. Reintroducing coarse aggregate (CA) to the constituents of UHPC mixtures is a solution promoted by many researchers for addressing the high production cost and insufficient shrinkage performance. Although adding CA to UHPC does not significantly subvert its high performance, it alters its microstructure and adjusts its characteristics. Accordingly, developing new material and structural models is imperative. This paper establishes compressive and tensile material models accounting for the effect of CA, and then employs the developed material models in structural-level analytical and numerical models for predicting the flexural responses of CA-UHPC slabs. The experimental parameters used in the material models are obtained from a collection of a wide range of experimental data available in the literature. The proposed models account for the size effect by scaling the tensile strain values of CA-UHPC in accordance with the member size. The proposed models are validated against previous test data, which confirm the capability of the developed models in capturing the response of CA-UHPC on a material level and a structural level.