Effective compressive strength of strut in CFRP-strengthened reinforced concrete deep beams following ACI 318-11

다국어 초록 (Multilingual Abstract)

Strut-and-tie model (STM) has been recommended by many codes and standards as a rationalmodel for discontinuity regions in structural members. STM has been adopted in ACI building code foranalysis of reinforced concrete (RC) deep beams since 2002. However, STM recommended by ACI 318-11is only applicable for analysis of ordinary RC deep beams. This paper aims to develop the STM for CFRPstrengthened RC deep beams through the strut effectiveness factor recommended by ACI 318-11. Two setsof RC deep beams were cast and tested in this research. Each set consisted of six simply-supportedspecimens loaded in four-point bending. The first set had no CFRP strengthening while the second wasstrengthened by means of CFRP sheets using two-side wet lay-up system. Each set consisted of six RC deepbeams with shear span to effective depth ratio of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00.The value of struteffectiveness factor recommended by ACI 318-11 is modified using a proposed empirical relationship in thisresearch. The empirical relationship is established based on shear span to effective depth ratio.

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