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An experimental investigation has been conducted to assess the damage control properties of ultra-high performance fiber reinforced concrete (UHP-FRC) in comparison to traditional concrete. Five identical reinforced concrete (RC) plates, with the exception of concrete material, are damaged gradually using repeated impact technique. Damage progression has been evaluated stepwise based on the change in dynamic parameters and validated by visual inspection, midpoint residual displacement and successive number of impact tests to each specimen. Test results showed that UHP-FRC exhibits superior damage characteristics. The damage rate of UHP-FRC materials are approximately in the range of 6–15% the damage rate of normal-strength concrete. [ABSTRACT FROM AUTHOR]

A comparative numerical study has been conducted to investigate the advantage of using ultra-high performance fiber reinforced concrete (UHP-FRC) material as an alternative to replace traditional cross sections of nuclear waste container. Three different finite element (FE) models of a typical waste container with identical dimensions and steel reinforcement detailing are developed. The cross section (HSC, HSC with steel liners, UHP-FRC) is varied parametrically to study its effect on mass, principal stresses, damage distribution, and plastic deformation. The current investigation considers the worst load case scenario by simulating accidental drops of the containers from a full stack height of 5.00 m. Two different accidental drop scenarios are considered (flat on-base and corner drop). The detailed 3D-FE models have been built considering nonlinear material properties and the simulations are performed using ABAQUS/Explicit. The material constitutive models have been calibrated based experimental tests. Based on the results of numerical comparative study, the UHP-FRC container suffered the least damage level and distribution among the three designs under considered loading cases. Both HSC, HSC with steel liners containers suffered high damage levels aligned between lid and container’s body which might lead to an opening of the container. On the other hand, stresses and damage levels at the lid to body interface are substantially improved in case of using UHP-FRC. [ABSTRACT FROM AUTHOR]

An experimental investigation has been conducted to collect fundamental data and to develop more understanding of the effect of steel reinforcement distribution on the dynamic response of reinforced concrete plates. Five high strength concrete (HSC) plates are tested using free-fall low-velocity impact technique. A total of 10 impact tests are conducted, including two tests on each specimen. The impact loads are applied at the mid-point of the HSC plates by dropping a 475 kg steel weight from a constant height of 4.15 m. Two parameters are investigated namely: the main bottom steel reinforcement ratio (1.0, 2.0, and 3.0%); and the steel reinforcement arrangement (single or doubly reinforced plates). The top reinforcement of all doubly reinforced plates is kept constant as shrinkage reinforcement of 10 mm diameter spaced at 210 mm. The experimental results are evaluated focusing on the impact force characteristics and the impact behaviors of reinforced concrete plates. The test program was successful in providing a simple method for validating impact test setup using impulse–momentum theorem. Results showed that the change of reinforcement ratio and/or reinforcement arrangement has no significant effect on impulse and absorbed energy values for same impact loading condition. Additionally crack pattern and failure mode are found to be more dependent on the reinforcement arrangement rather than reinforcement ratio. [ABSTRACT FROM AUTHOR]