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Bonding between rebar and steel fiber reinforced concrete (SFRC) has a major effect on reinforced SFRC members exposed to chloride environments where both steel fiber and reinforcement are subjected to corrosion damage. This paper presents an experimental study of the effect of corrosion on the bond behavior of reinforcement and SFRC. The test parameters include corrosion ratio, fiber fraction, and cover thickness‐rebar diameter ratio (c/d). Failure patterns, bond‐slip curves, and bond strength were compared. Increasing fiber fraction and c/d ratio enhanced bond strength and residual bond strength through improved confinement by the surrounding SFRC. With increasing corrosion, bond strength at first retained its initial strength or increased slightly and then reduced at corrosion ratios beyond 6–8.88%. A bond strength model is proposed which considers the combined effect of corrosion ratio, fiber fraction, and c/d ratio.

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Ni-P amorphous alloy is prepared by chemical reduction with hypophosphite and modified by introducing trace Pd to the alloy and depositing it on SiO2, which results in the great improvement on both the thermal stability and hydrogenation activity. The stabilizing effect of SiO2 and activating effect of Pd have been observed and discussed.

To better assess the safety of cementitious materials containing crushed waste oyster shells (WOS), the workability, mechanical properties (compressive strength and static elastic modulus) and durability (volume of permeable void (VPV), water absorption (WA) and total charge passed) were studied. The effects of replacing river sand with different content of crushed WOS (0, 10, 20 and 30%) on flowability, mechanical properties and durability of mortar have been revealed. The results indicated that the addition of WOS had a significant effect on the flow table of the mortar, and the loss ratio of FT varied from 25% to 39% at 120 min. Although the compressive strength (fc), static elastic modulus (Ec) and apparent density gradually decreased with the increase of WOS content, the mechanical properties were improved by prolonging the curing time. The incorporation of crushed WOS in mortar increased the VPV and WA, as well as the transport properties of mortar. The replacement of natural river sand with crushed WOS greatly increased the drying shrinkage of mortar. The substituted ratio–Gardner model exhibited the best accuracy in predicting the drying shrinkage development of crushed WOS mortar.