What is the difference between epoxy-coated steel bars and ordinary steel bars?

The surface of the ordinary steel bar is coated with epoxy resin coating, which is epoxy resin coated steel bar, and the coating thickness is generally 0.15mm~0.30mm. The use of such steel bars can effectively prevent the steel bars in harsh environmental conditions from being corroded, thereby greatly improving the durability of the engineering structure.

However, after the coating is applied, the bonding force between the steel bar and the concrete decreases, so the anchor length is required to be longer than that of the ordinary steel bar.

Under normal circumstances, the reinforcement anchorage length is: la, and the seismic requirement for reinforcement anchorage length is: lae (see 03G101-1 revised atlas). Epoxy resin coatings are generally used for rebar reinforcement. The anchorage length of rebar reinforcement cannot meet the requirements of lae, but the epoxy resin coating has high strength and corrosion resistance. This is no way in construction. It is better to pre-embed steel bars according to the anchoring length. The difference lies in the construction method used when it is not easy to embed or omit some parts. For example, the column reinforcement can be strengthened by 1:6, but it needs to be reinforced with epoxy resin outside the offset line of the column reinforcement (cut off the reinforcement of the offset column and replant the reinforcement at the correct position). The anchorage length of the reinforcement is not The length of lae that may meet the specification requirements. This is a reinforcement measure