Structural steel bond to concrete with waste aggregate

The article presents the results of bond tests of B500SP structural steel to concretes subjected to thermal stress. Concretes were designed purely on the basis on waste aggregate made of soft clay pottery with using two types of cements: Portland CEM 32.5R and aluminous cement Gorkal 70. In the research was used the method of direct pulling the steel rod out of the concrete cover (Pullout Test). For the tests were prepared four types of concretes: two bases of aluminous cement and two on Portland cement without additions. In the remaining mixtures containing the additive in the form of clinoptilolite, the method of simple weight replacement of the selected type of cement with clinoptilolite in the amount of 10% was used. Mineral puzzolana additives are intended to modify the phase composition of hardened cement slurry towards reducing the portlandite and changing the CaO/SiO2 ratio in the C-S-H phase. The results of the tests confirmed that the bond of the selected steel type to concrete on the recycle aggregate does not differ from the results achieved with natural aggregate. It was also confirmed that addition of clinoptilolite to concrete with Portland cement has beneficial effect when it is subjected to thermal stress.