Environmental effects on the behaviour of wrapped concrete compression members

Long term exposure to harsh environments deteriorates concrete and the need for repair or rehabilitation is evident. In order for a new repair material to become accepted it must be evaluated for durability in these harsh environments. This thesis, aimed at rehabilitating reinforced concrete columns and compares the effectiveness of glass fibre and carbon fibre wraps against a polyurethane/polyurea (Rockguard) coating that is currently used in the mining industry.;Over 200 concrete cylinders, 150 mm x 300 mm in size, are exposed to freeze-thaw and wet-dry conditions in salt water, fresh water, and air. Cylinders are wrapped with one of glass fibre, carbon fibre or Rockguard. Compression tests to failure are conducted after exposure periods of 50, 100, and 250 cycles. The performance of the cylinders is evaluated by comparing their stress-strain behaviour and their ultimate load capacity.;To compare laboratory and field conditions, six reinforced circular concrete columns (800 mm high x 200 mm diameter) with spiral reinforcement are placed in Lake Ontario near Kingston, Ontario. These columns consist of two non-wrapped and two each coated with glass fibre and Rockguard. During this study they are exposed to wave action, ultraviolet light, biotic life, ice and freezing. These columns are also tested to failure in axial compression.