Laboratory investigation of steel fibre reinforced sprayed concrete using a computed tomography method

• A laboratory method for investigation of cored samples of steel fibre reinforced sprayed concrete (shotcrete) is described. A pilot study on computed tomography (CT) has been conducted, with focus on how the technique can be used for non-destructive testing where the cores remain intact after scanning and evaluation. The CT method require advanced integrated equipment for X-ray scanning and image detection, together with a computerized visualization system that can reproduce a threedimensional virtual, transparent model of the studied object. The method is well suited to describe orientation and distribution of steel fibres within the concrete. Interfaces between rock-concrete and concrete-concrete, between layers of differentsequences ofspraying, can also be identified. The results from the CT investigations can be presented as qualitative data that in 3D shows locations of steel fibres, aggregates, etc., and also as quantitative data showing relative distributions of cement paste, aggregates, steel fibres and voids, which is here demonstrated by a selection of examples. The method is well suited for practical analysis of sprayed concrete in situ specimens and it is recommended that it is established as a standard method for special inspections and performance evaluation of rock support in tunnels and subspace structures.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Samhällsbyggnadsteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Civil Engineering (hsv//eng)

Keyword

Byggvetenskap

Civil and Architectural Engineering

Publication and Content Type

ref (subject category)

kon (subject category)