Development Length of Carbon-Fiber-Reinforced Polymer Bars in Self-Consolidating Concrete

摘要

Self-consolidating concrete (SCC) is widely used in the construction industry. SCC is a high performance concrete with high workability and consistency allowing it to flow under its own weight without vibration and makes the construction of heavily congested structural elements and narrow sections easier. Recently, fiber-reinforced polymer (FRP) reinforcements, with their excellent mechanical and non-corrosive characteristics are being increasingly used as a replacement for conventional steel reinforcement. In spite of the wide spread of SCC applications, the bond behaviour of FRP bars in SCC has not been fully studied. This paper presents the results of the first phase of an experimental study on the bond characteristics of sand coated CFRP bars in SCC beams. The experimental program of this phase consists of four SCC beams. All beams had the same geometric dimensions and were reinforced with single CFRP bar (12.7 mm in diameter). All beams were tested up to failure by four point bending regime with the shear span vary from 550 to 950 mm. The test results were used to evaluate the bond strength at different embedded lengths. These preliminary test results showed that the ACI 440.1R-06 [1] over estimated the development length of the CFRP bars in SCC, while CAN/CSA-S6-06 [2] equation is unconservative.