Investigation of fibre-reinforced thin repairs of concrete slabs or road pavements: Fid-Bau Portal

Investigation of fibre-reinforced thin repairs of concrete slabs or road pavements

Brandt, A.M. / Granju, J.L. / Wysokowski, A. / Glinicki, M.A. / Turatsinze, A. / Zurawicka, A. / Toumi, A.

The paper addresses the problem of interaction between a repair layer of fibre reinforced concrete and a plain concrete substrate. Theoretical considerations of the problem resulted in a conclusion that the debonding of the repair layer is the consequence of its cracking. The durability of its bond is principally affected by the post-crack residual tensile strength of the repair layer and its thickness. As well, the strength of the bond is efficient but only in a smaller extend. The objective of the investigation is an experimental verification of these theoretical results. It will be performed on full-scale repaired slabs, the paper presents its preparation. Performed laboratory tests covered various compositions of concrete reinforced with deformed-end steel fibres and amorphous metal fibres. A computer-controlled Instron testing machine was applied for direct tensile tests on homogeneous specimens as well as on bimaterial specimens, composed of a fibre concrete layer over a plain concrete layer. _The tensile behaviour was obtained as a function of fibre type and fibre content. On the basis of results obtained, a selection was made of fibre concrete compositions to be applied in full-scale testing of highway pavement slabs. The cracking and debonding of 5.25 m long concrete slabs seated on a compacted soil bed is to be tested using the full-scale testing facilities available in the Zmigrod's testing centre. The loading capacity available exceeds 2000 kN. The extend of the interface debonding will be monitored using an impact-echo device.