超高性能纖維混凝土(UHPFRC)為一種新興材料，能展現出比傳統混凝土更優秀的抗壓強度和韌性。目前已有許多研究顯示，計算超高性能纖維混凝土梁的撓曲強度時，須考慮混凝土抗拉強度的貢獻。然而根據現今的相關研究結果，仍未出現通用的計算方式，本研究的目的為驗證超高性能纖維混凝土梁計算撓曲強度的預測公式。為了探討超高性能混凝土梁之撓曲行為，設計了10支梁試體，設計參數為縱向鋼筋比(2.8%、5.9%、11.1%)、纖維量(2%、0.75%)、纖維種類(端鉤型、直線型)、澆置方式(標準澆置、反向澆置)。
根據ACI 544中的力學模型，並透過先前的超高性能纖維混凝土梁之四點彎矩試驗結果，建議極限時拉力側矩形應力塊的折減係數值，再利用先前文獻中的實驗結果，驗證此強度預測分析模型的精確性。最後建議在模擬梁之撓曲行為時，可使用的材料分析模型。
研究結果顯示，和實驗結果比較後，本研究建議的撓曲強度預測公式，可合理預測梁斷面的降伏撓曲強度。

The objective of this study is to evaluate the model that predicts the nominal flexural strength of ultra-high performance fiber reinforced concrete (UHPFRC) beams. In order to investigate the flexural behavior of UHPFRC beams, ten beam specimens were designed with different longitudinal rebar ratio, fiber volume fraction, fiber types and placing directions. Based on ACI 544 model, the factor relating depth of the equivalent rectangular tension stress block is proposed with the four-point bending tests result. The verification was carried out with the test result of previous researches to check the accuracy of the calculated flexural strengths. Furthermore, according to the four-point bending tests result, the material models of UHPFRC beams are suggested. The result shows that the ultimate moment capacity of UHPFRC beams can be predicted by the proposed model when compared to the experimental results.

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