根據ACI318-08,梁可分為細長梁及深梁兩種形式,其分類是以跨度長(a)及斷面深度(h)之比值來做區分,比值小於2時稱之為深梁。在計算深梁之剪力強度現今均是以壓拉桿理論為主,但目前提出之壓拉桿理論中,一般均使用在矩形斷面,對於非矩形斷面梁上應用,有其困難存在。但在一般建築物當中,樓版及矩形梁形成之T形斷面梁,就屬非矩形斷面類型,如何利用壓拉桿理論準確評估T形斷面梁之剪力,及樓版是否對剪力有貢獻,為本次研究方向。 本實驗之試體針對不同之翼版大小作設計,矩形梁及T形梁共8根試體。由實驗結果得知,翼版之大小對於剪力強度有其影響,並且提出現有之加拿大CSA壓拉桿理論在評估斜向壓桿強度有失準的情況。最後提出有效翼版寬及斜向壓桿強度之假設,來改進CSA之壓拉桿理論。 According to ACI-308-08,the RC beam can separate into slender beam and deep beam. If a/h < 2, it is classified as deep beams. Recently, we use Strut and Tie Model to calculate the shear strength. But in this theory, it is difficult to apply to non-rectangular beam. Among the normal structures, T-beam, which is formed from flange and rectangular beam, belongs to the type of non-rectangular beam. The research focuses on the effect of flange on shear strength. The specimen of this experiment designs different flange areas, included rectangular beam, T beam…. all 8 specimens. The result of this experiment confirms that different flange areas really affect shear strength and that strut and tie model, which is issued by CSA Code, inaccurately assess diagonal strut strength. Finally, The effect flange width is mainly adopted in to the evaluation of shear strength of T-section short beam by means of strut and tie model methodology