Title: Dynamic Behaviour of Two UHPC Matrixes in Direct Tension
Author(s): Ezio Cadoni, Deborah Briccola, Matteo Dotta, Daniele Forni
Publication: Symposium Paper
Appears on pages(s): 11-18
Keywords: UHPC; High strain-rate; Split Hopkinson Tensile Bar; Tensile strength; DIF
Understanding the dynamic response of cementitious materials is one of the key issues in the design and assessment of structures subjected to blast or impact loadings. The response of the material to these dynamic actions can be dramatically different and it must be carefully evaluated. The experimental response in direct tension of two ultra-high-performance concretes, tested in a wide range of stress-rate from 0.3 MPa/s (0.044 ksi/s) to 1.3 TPa/s (188’549 ksi/s), is presented in the paper. An electro-mechanic universal machine, a Hydro-Pneumatic Machine, and a Split Hopkinson Tensile Bar device were used to test low, medium, and high stress rates, respectively. The results showed a marked rate dependency of these materials. The resulting DIFs highlighted how Model Code 2010 underestimate the material dynamic strength both at medium and high stress-rate.