Development of a new test method for Mineral Based Composites: Wedge splitting test

The well-known wedge splitting test, often used for characterizing brittle materials has been modified and adapted to testing MBC-reinforced concrete under splitting load. MBC (Mineral Based Composites) is a newly developed strengthening system for existing concrete structures where FRPs, mainly CFRP grids are externally bonded to the concrete surface by means of cementitious bonding agents.

Crack development, crack patterns, crack opening displacement (COD) versus splitting load and fracture energy are investigated and evaluated. Development of a suitable test specimen and test setup has been accomplished. Bond provided by both mortars was excellent leading to CFRP rupture. By applying PVA-reinforced ductile ECC as bonding agent, improved performance, significantly higher fracture energy, multiple cracking and enhanced ductility were observed, caused by improved bond between grid and mortar due to the refined grain structure, the bridging effect of the embedded fibres working against crack opening and via direct mechanical interlock with the grid