新世代高性能混凝土抗裂指標與力學性質研究

CRACK RESISTANCE INDEX AND MECHANICAL PROPERTIES OF NEW GENERATION HIGH PERFORMANCE CONCRETE

廖文正(Wen-Cheng Liao) ； 張家維(Jia-Wei Jhang) ； 吳丞駿(Cheng-Jun Wu)

《中國土木水利工程學刊》 34卷1期 (2022/03) Pp. 73-87

https://doi.org/10.6652/JoCICHE.202203_34(1).0008

摘要

在發展了近50年的高性能混凝土之應用已臻成熟的台灣，應朝新世代高性能混凝土繼續提升；新世代高性能混凝土除了保有高流動性、更高抗壓強度外，更應有在新拌及硬固時具抑制收縮裂縫能力，並完全跳脫傳統混凝土的力學限制，在承受大變形、甚至是受拉下，都還能維持相當強度，保護鋼筋完全伸展，在可觀變形下仍能維持發揮構件設計強度，即受拉時呈應變硬化的特徵。因應未來模擬、設計及施工需求，本研究分別針對新世代高性能混凝土新拌及硬固性質進行一系列材料實驗，提出相關抗裂指標及基本組合律、力學性質建議公式，供後續實務應用設計使用。本研究分別對塑性收縮及乾燥收縮進行實驗及評估其抑制收縮裂縫的能力；並針對設計或模擬所需之各項力學基本性質進行各項力學實驗，也同步建立資料庫進行迴歸及整理國內外鋼纖維混凝土之預測公式，透過比較文獻於資料庫中擬合表現來挑選合適預測式，並參照本研究實驗結果進行最佳化分析，最終提出適用於新世代高性能混凝土之建議公式，供產官學界直接參考及使用。

關鍵字

鋼纖維 ； 高性能混凝土 ； 應變硬化 ； 收縮裂縫

並列摘要

High performance concrete (HPC) has been developed for nearly 50 years. In Taiwan, where HPC has been well developed and widely applied, concrete should move towards a new generation of multi-functional high performance concrete. In addition to high flowability and higher compressive strength, new generation HPC shall not only have excellent crack resistance from shrinkage, but completely beyond the mechanical limitations of traditional concrete. New generation HPC can maintain considerable strength even under large deformation or even under tension, and secure the steel bars fully developed; that is, it exhibits the characteristics of strain hardening under tension. In response to future simulation, design, and construction practical demands, this research proposes relevant crack resistance index, basic constitution laws, and suggested formulas for mechanical properties according to its fresh and hardened properties. In this study, resistance crack propagation from plastic shrinkage and drying shrinkage were evaluated for new generation HPC. In terms of the basic mechanical properties for design or simulation, this research has also conducted experiments and established a database for regression to propose formulas for further reference and use by the industry, government and academia.

並列關鍵字

steel fiber ； high performance concrete ； strain hardening ； shrinkage crack

參考文獻

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