PROPERTIES OF PRE-TENSIONED PRESTRESSED CONCRETE MEMBERS SUPPLIED WITH CATHODIC PROTECTION FOR TEN YEARS

摘要

This paper evaluates the effect of cathodic protection applied to prestressed concrete members. These members were T-type pretensioned PC beams, two of which had no-cathodic protection and three that were supplied with various levels of cathodic protection. NaCl was added at mixing stage to accelerate corrosion of the PC strands. The beams were exposed to severe environmental conditions for ten years. Measurements were carried out by way of electrical-chemical tests on the embedded PC strands, load-carrying tests on the beams, and after the beams were broken, visual observation of corrosion and the tensile tests on the PC strands. These test results through and after ten years indicated the followings: 1) beams protected with some type of cathodic protection had the same loading properties as beams tested at the initial stage (age zero years), 2) PC strands embedded in concrete had no corrosion for two types of anode materials and maintained suitable mechanical properties.