摘要(英) |
Since 2007 in Taiwan, the National Center for Research on Earthquake Engineering (NCREE) has launched the Taiwan New RC Project. This study, belonged to one of topics in the project, was designed four rectangular cantilever beams with a/d=3.0 and different stirrup layouts. The objective of this study is to investigate the seismic behavior of these specimens.
The shear strength of the beam HRB-S1b, which had shear stirrups with the combination of U-shape ties and lateral 90°-135° degree tie bars on the top of U-shape ties, did not show significantly different in comparison with the beam HRB-S1a, which had standard close-type stirrups, when the hysteresis loop sustained until DR(drift ratio)=3.5%. However, after DR=3.5%, the beam HRB-S1b had earlier shear degradation comparing with the beam HRB-S1a.
The other two specimens (HRB-S2a and HRB-S2b) were the beam HRB-S2a, which had shear stirrups with 90°-135° degree hook vertically taking turn to tie the middle flexural bar, and the beam HRB-S2b, which had no take-turn 90°-135° hook arrangement in a substandard method. The beams HRB-S1 series had contrary results to the beams HRB-S2 series. That is, the beam HRB-S2b had lower shear strength than the beam HRB-S2a when the hysteresis loop reached DR=3.5%. However, they (HRB-S2a and HRB-S2b) had similar tendency in the shear strength degradation.
Test results indicated that the measured maximum stress of stirrups of all the specimens ranges from 680MPa to more than 895MPa (the actual yielding stress). In the fore-mentioned specimens, concrete still had shear contribution in plastic hinge zone.
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參考文獻 |
[1] ACI Committee 318, Building Code Requirement for Structural Concrete, ACI318-11 & Commentary, American Concrete Institute, 2011.
[2] ACI Innovation Task Group 4, Report on Structural Design & Detailing for High Strength Concrete in Moderate to High Seismic Applications, American Concrete Institute, 2007.
[3] NZS3101, Concrete Structures Standard, The design of Concrete Structures & Commentary on the Design of Concrete Structures, New Zealand Standard, 2006.
[4] NIST GCR 14-917-30, Use of High-Strength Reinforcement in Earthquake-Resistant Concrete Structures, National Institute of Standards and Technology, 2014.
[5] N.J. Brooke, “The Effect of Reinforcement Strength on the Overstrength Factor for Reinforced Concrete Beams,” Pacific Conference on Earthquake Engineering, 2011.
[6] N.J. Brooke, “Improving the Performance of Reinforced Concrete Beam-Column Joints Designed for Seismic Resistance,” The University of Auckland, Thesis of Ph.D., Nov. 2011.
[7] ACI Committee 363, State-of-the-Art Report on High-Strength Concrete, American Concrete Institute, 1997, pp. 23-24.
[8] ACI Committee 374, Acceptance Criteria for Moment Frames Based on structural Testing and Commentary (ACI 374.1-05), American Concrete Institute, Farmington Hills, MI, 2005, pp. 1-9.
[9] T. Paulay, and M.J.N. Priestley, Seismic Design of Reinforced Concrete and Masonry Building, John Wiley & Sons, New York, 1992.
[10] P.E. Kavitha, “Strain Transformation and Rosette Gage Theory”, Georiga Institute of Technology School of Aerospace Engineering, AE3145 Laboratory, 2009, pp. 1-7.
[11] J.C. Varney, M.D. Brown, O. Bayrak, and B.W. Poston, “Effect of Stirrup Anchorage on Shear Strength of Reinforced Concrete Beams”, ACI Structural Journal, V.108, No.4, July-August. 2011, pp. 469-478.
[12] 洪立彥,「New RC梁撓曲剪力行為研究」,國立中央大學,碩士論文,民國一百零三年。
[13] 廖于興,「New RC梁撓曲剪力設計研究」,國立中央大學,碩士論文,民國一百零四年。
[14] 內政部建築研究所,「高強度鋼筋混凝土應用在高樓層建築物之耐震性能探討」,民國一百年。
[15] 陸景文,「台灣地區混凝土抗壓強度與彈性模數特性研究」,國立台灣大學,博士論文,民國一百零四年。
[16] 經濟部標準檢驗局,土木材料及品質管理相關國家標準(CNS規範),民國九十七年。
[17] 中國土木水利工程學會,混凝土工程設計規範與解說,土木401-100,民國一百年。
[18] 財團法人國家實驗研究院國家地震工程研究中心,「新世代超高強度鋼筋混凝土結構系統研發」,民國一百年。
[19] 內政部建築研究所,「超高強度鋼筋混凝土建築結構設計施工審核要項之研擬」,民國一百零二年。 |