現行傳統鋼橋柱受地震作用下非彈性變形通常集中於柱底，容易造成柱底產生局部挫屈或銲道開裂，而本研究採用預選塑性區鋼橋柱的設計觀念，由中鋼最新製程之LP鋼板(Longitudinally Profiled Steel Plate)設計四組橋柱試體，利用LP鋼板板厚漸變的特性，用來降低柱底與基座交界面之應變需求，使預先選定之區域產生均勻降伏，消散能量發揮其韌性，可將柱底容易產生之局部挫屈行為往上提升於預選塑性之區域，並改變其漸變段之高度，藉以控制鋼橋柱在地震下的破壞位置，以方便日後發生大地震後的破壞檢測與維修補強之動作。從研究結果顯示：(1)從文獻中所提出的漸變率作為設計考量，可有效發揮LP鋼板之特性並得到LP鋼橋柱最佳設計。(2) LP鋼橋柱的消能能力與挫屈行為皆比傳統鋼橋柱為佳，並輔以有限元素分析來印證其試驗結果。

It is generally recognized that the inelastic deformation of steel bridge usually concentrates at the bottom of the column under the earthquake, which will easily cause local buckling and cracking of welds. The use of longitudinally profiled steel plate (LP steel plate) producing by CSC can be applied in this situation. Columns made by LP plate which can effectively reduce the demand of strain at the bottom, bring uniform yielding at selected zone and perform excellence ductility by the character of longitudinally profiled. The damage location of columns could be controlled by changing the height of tapering region.
In this study, four specimens designing by the concept of pre-selected plastic zone. The damage location of columns could be controlled by changing the height of tapering region. The results indicated that：（1）The taper ratio provided form this study can use the characteristics of LP steel plates efficiently. A correct design approach of the greatest LP steel bridges is suggested. （2）The behavior of energy dissipation and local buckling of LP steel bridge column are better than the traditional steel bridge columns. Comparison of the result from finite element method to the experiment is established.

[1] 內政部營建署，「鋼構造建築物鋼結構設計技術規範（二）鋼結構極限設計法規範及解說」，2010。
[2] 內政部營建署，「鋼結構施工規範」，2008。
[3] 交通部，「公路橋梁耐震設計規範修」，2008。
[4] 交通部，「鋼橋柱極限設計法規範及解說草案之研究(二)」，三民書局，2004。
[5] 財團法人鋼材俱樂部阪神高速道路公團，研究報告書，2000。
[6] 陳傑，「預選塑性區鋼橋柱耐震行為之研究」，國立台灣科技大學營建工程系，博士論文，陳生金指導，2008。
[7] 陳生金，「鋼結構行為與設計」，科技圖書，2009。
[8] 羅章貴、許中聘、兵亮志、張滿福，「精進之路–中鋼LP鋼板開發與應用」，鑛冶，第56卷，第一期，2012。
[9] AASHTO. LRFD Bridge Design Specifications,“American Association of State Highway and Transportation Officials,”; 2010.
[10] ATC 32, Improved Seismic Design Criteria for California Bridges: Provisional Recommendations, Applied Technology Council, Cal-trans, (1996).
[11] Aoki T, Takaku T, Fukumoto Y, Susantha KAS,“Experimental Investigation for Seismic Performance of Framed Structures having Longitudinally Profiled Plates,”Journal of Constructional Steel Research 2008; 64: 875-881.
[12] Bruneau M.,“Performance of Steel Bridge during the 1995 Hy-ogoken-Nanbu, (Kobe, Japan) Earthquake, a North American Per-spective,”Engineering Structures 1998; 20(12): 1063-1078.
[13] Chen SJ, Yeh CH, Chu JM,“Ductile Steel Beam-to-Column Connections for Seismic Resistance,”Journal of Structural Engineering 1996; 12(11): 1169-1177.
[14] Fukumoto Y, Uenoya M, Nakamura M, Saya H,“Cyclic Performance of Stiffened Square Box Columns with Thickness Tapered Plates,”Steel Structures 2003; 3: 107-115.
[15] Fukumoto Y, Takaku T, Aoki T, Susantha KAS,“Innovative Use of Profiled Steel Plates for Seismic Structural Performance,”Advances in Structural Engineering 2005; 8(3): 247-257.
[16] Japan Road Association,“Specifications for Highway Bridges,”Part Ⅱ: Steel bridges, Tokyo(1996a).
[17] Japan Road Association,“Specifications for Highway Bridges,”Part Ⅴ: Seismic design, Tokyo(1996b).
[18] Kumano T, Tukamoto Y, Hiroe A, Aoki T,“Experimental Study (1) on Seismic Performance of Steel Piers with LP plates (Mold line and Tapering Ratio),”Proceeding of the Annuals of JSCE, 2003；No.58 (in Japanese).
[19] MacRae GA, Kawashima T.,“Seismic Behavior of Hollow Stiffened Steel Bridge Columns,”Journal of Bridge Engineering 2001; 6(2): 110-119.
[20] Miki T. and Kawada S., “An experimental study on the elasto-platic hysteretic behavior of partially tapered steel beam-columns,”Journal of Structural Mechanics and Earthquake Engineering, JSCE, Vol. 647, No.I-51, 345-355(in gapanese).
[21] Murakami S. and Nishimura N.,“Ultimate strength evaluation of tapered plate in compression,”Proc. 5th International Colloquium on Stability and Ductility of Steel Structures,Nagoya, 133-140 (1997).
[22] Nishikawa K., Yamamoto S., Natori T, Terao K, Yasunami H, Terada M,“Retrofitting for Seismic Upgrading of Steel Bridge Columns,”Engineering Structures 1998; 20(4-6): 540-551.
[23] Nishikawa K., Murakoshi J., Takahashi M., Okamoto T., Ikeda S.,Morishita H.,“Experimental study on strength and ductility of steel portalframe bridge pier,”Journal of Structural Engineering, JSCE 45A 1999;235–44.
[24] Susantha KAS, Aoki T., Kumano T.,“Strength and Ductility Evaluation of Steel Bridge Piers with Linearly Tapered Plates,”Journal of Constructional Steel Research 2006; 62: 906-916.
[25] Takaku T., Fukumoto Y., Aoki T., Susantha KAS.,“Seismic Design of Bridge Piers with Stiffened Box Sections using LP Plates,”13th World Conference on Earthquake Engineering 2004; Paper No. 3224, Vancouver, B. C., Canada.
[26] Timoshenko, S.P., and Gere, J.M., Theory of Elastic Stablilty, 2nd ed., McGraw-Hill, New York(1961).
[27] Usami T., Fukumoto Y.,“Local and Overall Buckling of Welded Box Columns,”Journal of the Structural Division 1982; 108(3): 525-542.
[28] Usami T., Fukumoto Y.,“Deformation Analysis of Locally Buckled Steel Compression Members,”Journal of Constructional Steel Research 1989; 13(2-3): 111-135.
[29] Usami T.,“A Simplified Analysis of the Strength of Stiffened Box Members inCompression and Bending,”Journal of Constructional Steel Research 1990; 17(3): 237-247.
[30] Usami T., Ge HB.,“Cyclic Behavior of Thin-Walled Steel Struc-tures-Numerical Analysis,”Thin-Walled Structures 1998; 32: 41-80.
[31] Uenoya M., Nakamura M., Fukumoto Y., and Yamamoto S.,“An experimental study on the elastic-plastic hysteretic of tapered column,”Journal of Structural Engineering, JSCE, Vol. 9, No.33, 25-35 (2002).
[32] Yamamoto R., Aoki T., Kumano T., TuKamoto Y,“Experimental Study (2) on Seismic Performance of Steel Piers with LP plates (Stiffeners and Tapering Ratio),”Proceeding of the Annuals of JSCE, 2003；No.58 (in Japanese).
[33] Zheng Y., Usami T., Ge HB.,“Ductility of Thin-Walled Steel Box Stub-Columns,”Journal of Structural Engineering 2000; 126(11): 1304-1311.