Experimental and numerical study of dynamic material properties of fibre reinforced concrete

Zhuo Xu

    Research output: ThesisDoctoral Thesis

    626 Downloads (Pure)

    Abstract

    [Truncated abstract] This thesis presents both numerical and experimental investigations on the dynamic resistance of fibre reinforced concrete (FRC) materials. The effects of fibre shapes, material properties and dosage on the dynamic properties of FRC, including the Dynamic Increase Factor (DIF) of both the compressive and tensile strength, dynamic stress-strain relationship, energy absorption capacity, fibre-metrics mesoscopic interaction and failure modes are studied through experimental tests and numerical simulations. The main content and achievement of this thesis are summarised blow. In Chapter two, a numerical method is developed to simulate dynamic impact tests on steel fibre reinforced concrete (SFRC) specimens to study the dynamic material properties of SFRC. In the analysis, an axisymmetric mesoscale SFRC model is developed with distinctive consideration of the fibres, aggregates and cement mortar to investigate the dynamic failure behaviour of SFRC material under impact loading at different strain rates. The aggregates are modelled with random size and distribution in the SFRC specimen. The hooked-end steel fibres are also randomly distributed in the specimen with random orientations. The developed model is used to numerically simulate a Split Hopkinson Pressure Bar Test (SHPB) on SFRC specimens. Numerical results are compared with available experimental data to verify the developed model. The comparison indicates that the mesoscale numerical model can reliably simulate SHPB tests on SFRC and concrete specimens. The developed numerical model is then used to perform a series of simulations of SFRC specimens with different volume fractions of steel fibres or without steel fibre under dynamic impact loads of different loading rates. From the numerical results, the influences of steel fibres on dynamic material properties, in particular the Dynamic Increase Factor (DIF), and on dynamic failure mechanism of SFRC are discussed.
    Original languageEnglish
    QualificationDoctor of Philosophy
    Publication statusUnpublished - 2011

    Fingerprint

    Dive into the research topics of 'Experimental and numerical study of dynamic material properties of fibre reinforced concrete'. Together they form a unique fingerprint.

    Cite this