2018-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/705370摘要：本研究計畫於後拉預力混凝土梁中使用高強度非預力橫向鋼筋(SD 790)與縱向鋼筋(SD 690)以及高強度混凝土(70 MPa)，以降低預力梁擁擠的鋼筋配置，提升預力梁施工性，確保結構性能。本計畫初步的文獻回顧顯示，過去預力梁試驗中的非預力橫向與縱向鋼筋降伏強度最高約500 MPa，因此據以發展所得之撓曲與剪力強度計算公式於SD 690與SD 790高強度鋼筋之適用性存疑。本研究為三年期研究，前兩年研究使用SD 690與SD 790鋼筋預力梁之剪力行為，預計測試24座大尺寸預力梁試體，設計變數擬為預力量、剪力跨深比、橫向鋼筋用量與種類，最終將發展剪力強度計算公式。第三年則研究撓曲行為，預計測試12座大尺寸預力梁試體，試驗變數包括預力量、非預力縱向鋼筋用量、以及非預力縱向鋼筋種類，最終將發展撓曲強度計算公式。本計畫綜合三年的研究，將可完整釐清使用高強度鋼筋預力梁的撓曲與剪力行為，提出設計方法以及規範修訂建議，推廣高強度SD 790與SD 690鋼筋於預力梁之使用。<br> Abstract: This proposal proposes to use high-strength nonprestressed transvers reinforcement (SD 790) and longitudinal reinforcement (SD 690) together with high-strength concrete (70 MPa) in post-tensioned concrete girders. The use of such high-strength reinforcement can reduce the amount of reinforcement and hence decreases reinforcement congestion. This leads to better constructability and structural performance. Preliminary literature review shows that the highest yield strength of nonprestressed transverse and longitudinal reinforcement previously examined is approximately 500 MPa, much lower the yield strengths of SD 690 and SD 790 reinforcement. Therefore, it is questionable to use the flexural and shear strength equations available in the literature in prestressed girders with SD 690 and SD 790 reinforcement. This proposed research is a three-year study. In the first two years, shear behavior of prestressed girders with SD 690 and SD 790 reinforcement will be investigated. Twenty four large-scale prestressed girders will be tested. The design variables will include the amount of prestress, shear-span-to-depth ratio, quantity and type of transverse reinforcement. Based on the test results, shear strength equations will be developed. In the third year, the flexural behavior of prestressed girders with SD 690 and SD 790 reinforcement will be studied. The design variables will include the amount of prestress, and amount and types of nonprestressed longitudinal reinforcement. Twelve large-scale prestressed girders will be tested. Based on the test results, flexural strength equations will be developed. The deliverables of this three-year research will include complete flexural and shear design equations and code implications for post-tensioned concrete girders with SD 690 and SD 790 reinforcement. The results of this proposed research will promote the use of SD 690 and SD 790 reinforcement in prestressed concrete girders.預力梁高強度鋼筋SD 690鋼筋SD 790鋼筋高強度混凝土剪力撓曲prestressed girdershigh-strength reinforcementSD 690 reinforcementSD 790 reinforcementhigh-strength concreteshearflexure