Flowable high-strength system as repair material

摘要

The use of steel fibres in concrete or mortar is known for its potential to enhance the flexural toughness, the energy dissipation and the impact resistance for many structural applications, especially in building repairs and other civil engineering works. The use of steel fibres in flowable mortar provides a great advantage in arresting cracks and enhancing the flexural rigidity of the composite material. Hence, this experimental investigation was performed to provide a clear indication and understanding of the behaviour and structural performance in engineering construction. The experimental tests conducted were: density, compressive strength, splitting tensile strength, flexural strength and toughness indices tests. These tests are required to show that the best performance of high-strength flowable mortar or high-strength flowing concrete could be fulfilled by using steel fibres and the optimal percentages of silica fume as partial replacement of cement. The conductivity of the repair material was evaluated by adoption of some combined systems of repair materials with concrete to determine the bond action of this repair material (flowable high-strength system). The results indicate that the high-strength flowing concrete has an excellent performance in terms of compressive strength for the repaired system. On the other hand, the high-strength flowable mortar improves significantly the tensile strength of the repaired system.