GLASS FIBRE REINFORCED CONCRETE (GFRC) PROTECTIVE COATING FOR WATERPROOF LAYERS ON CONCRETE BRIDGE AND CULVERT

摘要

To keep a concrete bridge or culvert in good condition it should be avoided that a waterproof layer on girder or culvert will be cracked or crushed. Such cracks were found to existed in protective coatings of waterproof layers from bituminous mortar, bituminous concrete and steel mesh reinforced mortar in the China Railway system. Steel fiber reinforced concrete is presently used in protective coatings, but steel fibers itself in protective coatings can damage a waterproof layer, moreover, surfaces of SFRC can not easily be finished. Now, the use of GFRC is promoted for improving the performance of protective coatings. Cem-fil alkali resistant HP fibres were provided by Cem-fil international Ltd.. These fibres are used in bundles, that do not breakdown during mixing, providing the improved properties to both in-situ and pre-cast concrete elements. Based on the recipe offered by Cem-fil, four mixing have been designed to meet the needs of a protective coating, a 20 kg/m~3 addition had significant effects on LOP, MOR and fracture energy of GFRC, especially at younger age. This composite will meet the specifications for protective coatings of a waterproof layer on a concrete bridge