台灣位於環太平洋地震帶，板塊活動頻繁，常造成地震之發生，並常有強烈的有感地震發生，且因地狹人稠之緣故，高層建築漸漸已成為未來之趨勢。一般高層建築均採用施工效率較高、韌性較佳之鋼骨結構，但因採用鋼骨結構之高層建築勁度較差、造價昂貴且耐火性差，一般較不適用於住宅建築，使得鋼骨構造之發展受到侷限。為改善鋼骨構造之缺點，結構工程上發展出鋼骨鋼筋混凝土構造(SRC)，其不但保有鋼骨構造韌性佳之優點外，亦兼具RC構造勁度大、隔音、防爆效果及使用性較佳之優點。
本研究之對象主要為包覆型SRC結構，包覆型SRC結構具有眾多優點，在鋼骨四周以鋼筋混凝土包覆，可增加鋼骨之側向勁度、提升鋼骨抵抗受壓挫屈之能力、以及作為鋼骨之防火被覆，同時鋼骨亦可對四周包覆的混凝土產生圍束作用，提升其抗壓強度與韌性。由於其眾多優點，包覆型SRC近年來有漸受歡迎之趨勢。
過去的研究已指出，既有SRC規範對於柱箍筋耐震設計需求之計算公式，無法適當地考慮鋼骨對於混凝土圍束效應之影響，以及軸力對於箍筋需求量之影響。針對前述問題，過去的研究已針對I型、十字型與T型等包覆型SRC柱斷面，提出箍筋耐震設計用量之規範修正建議，並已透過一系列的構件試驗加以驗證。本研究之目的在於進一步透過大尺寸多跨構架試驗研究，觀察含包覆型SRC柱之構架耐震行為，並驗證前述構件層面之研究成果於構架結構之適用性。

Located on the Pacific Ring of Fire, Taiwan experiences numerous “feel able” earthquakes every year. Due to the dense population in Taiwan, high-rise buildings have become the trend for buildings of the future in Taiwan. High-rise buildings typically use steel structures due to the high ductility for seismic design and high construction efficiency. However, steel structures have low stiffness, high cost, and low fire resistance. Thus, steel structures are not suitable for residential buildings. Steel reinforced concrete (SRC) structures can improve the drawbacks of steel structures mentioned above. SRC structures not only preserve the high ductility advantage of steel structures but also have the advantages borrowed from reinforced concrete structures, i.e., high stiffness, reduced vibration and improved sound proof.
This research focuses on concrete-encased SRC structures. The concrete-encased SRC structures have several advantages compared to other types of structures. Concrete provides lateral support to the embedded structural steel member, thus increasing the buckling resistance of the steel member and hence increasing the ductility and energy dissipation capacity. Moreover, concrete serves as fireproof to the steel member. The steel member provides confinement to concrete, increasing compressive strength and ductility of concrete. Due to the advantages mentioned above, concrete-encased SRC structures have become more and more popular in recent years.
Previous research has indicated that existing Taiwanese SRC code provisions on the required amount of column transverse reinforcement for seismic design cannot properly include the confinement effect from the steel member to concrete and does not consider the effect of axial load. The principal investigator of this proposal has proposed a design model to address this issue and has been verified by testing of large-scale members with various cross sectional shape of steel members, i.e., I shape, cross H shape, and T shape.
A large scale SRC frame structure will be constructed and tested in this research. The SRC frame will be designed with various cross-sectional shapes of steel members with the amount of column transverse reinforcement determined based on the proposed model. Pseudo-dynamic and cyclic loading testing will be carried out. The objectives of this research are to examine the seismic performance of a SRC frame designed based on the proposed model for the amount of column transverse reinforcement and to further verify the model for future code implementation.

[1] ACI Committee 318, 2011. ACI 318-11/318R-11, Building Code Requirements for Structural Concrete and Commentary. American Concrete Institute.
[2] AISC 341-10, Seismic Provisions for Structural Steel Buildings. American Institute of Steel Structure.
[3] AISC LRFD 2005, Load and Resistance Factor Design Specification. American Institute of Steel Structure.
[4] AISC 318-14, Building code requirement for structural concrete. American Concrete Institute.
[5] AISC Design Examples Version 14.0. American Institute of Steel Structure.。
[6] James M. Ricles, and Shannon D. Paboojian. (1994). Seismic performance of steel-encased composite columns. Journal of Structural Engineering.
[7] Hsu, H. L., Jan F. J. and Juang, J. L., Performance of composite members subjected to axial load and bi-axial bending. Journal of Constructional Steel Research (2009).
[8] Hoang T.T.T., Seismic Behavior of Steel Reinforced Concrete Columns with Axial Compressive Force, NTUST Master Thesis (2009).
[9] Chen, CC., Suswanto B., Lin Y.J., Behavior and Strength of Steel Reinforced Concrete Beam-column Joint with Single Side Force Inputs. Journal of Constructional Steel Research, 65 (2009) 1569-1581.
[10] Cheng-Cheng Chen∗ , Keng-Ta Lin, Behavior and strength of steel reinforced concrete beam–column joints with two-side force inputs. Journal of Constructional Steel Research 65 (2009) 641–649.
[11] Priestly, M. J. N., and Paulay, T.(1992). Seismic Design of Reinforced Concrete and Masonry Buildings. John Wiley & Sons, lnc.
[12] K.J. Elwood, J. Maffei, K.A. Riederer, and K. Telleen. Improving Column Confinement. Concrete International, 2009-11.
[13] 陳正誠、詹鎧慎，(2012)，「含軸壓力包覆型鋼骨鋼筋混凝土柱之撓曲行為」，行政院國家科學委員會成果報告，NSC 99－2221－E－011－038。
[14] Mander, J. B., M. J. N. Priestley and R. Park (1988). "Theoretical stress-strain model for confined concrete." Journal of Structural Engineering 114(8): 1804-1826.
[15] Priestley, M. J. N. and R. Park (1987). "Strength and Ductility of Concrete Bridge Columns under Seismic Loading." ACI Structural Journal 84(1): 61-76
[16] Mirza SA, Skrabek BW. Statistical analysis of slender composite beam-column strength. Journal of Structural Engineering, ASCE 1992; 118(5): 1312-31.
[17] Chen CC, Lin NJ. Analytical model for predicting axial capacity and behaviour of concrete encased steel composite stub columns. Journal of Constructional Steel Research 2006; 62:424-33: 1312-31.
[18] E. Ellobody, B. Young. Numerical simulation of concrete encased steel composite columns. Journal of Constructional Steel Research 67 (2011) 211-222
[19] Dhakal R, Maekawa K. Path-dependent cyclic stress-strain relationship of reinforcing bar including buckling. Eng Struct 2002; 24:1139-4
[20] 內政部建築研究所，(2011)，「鋼骨鋼筋混凝土構造設計規範與解說」。