Vol. 6A (6 3 ) Fundamental consideration on the redundanc of a steel Langer bridge based on nonlinear finite element analsis Isao Saiki, Kota Kawamura, Kaname Iwatsubo, Tetsuo Iwakuma -57 6-6-6 63- -- 66-5 67 Ph.D. -57 6-6-6 Since the accident of the I-35W Mississippi river bridge in 7, a lot of research on the redundanc based on numerical analsis has been conducted. Although there is a lot of research related to truss bridges and girder bridges, there is few research about Langer bridge. Since Langer bridges are regarded as staticall indeterminate structure in the design process, we can epect that Langer bridges are more redundant than staticall determinate structures such as truss bridges. However there is no research on quantitative evaluation of the redundanc of Langer bridges so far. In this paper, influence of modeling of panel points and slab on evaluation of the redundanc of steel Langer bridges is investigated through a series of nonlinear finite element analses. Ke Words: steel Langer bridge, nonlinear finite element analsis, redundanc, failure of hangers. 7 ),) 3) I-35W 4),5),6),7) 5) / Corresponding author E-mail: isao.saiki.a4@tohoku.ac.jp ) Su et al. ) ) ),) -6-
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アーチリブストラット剛体要素 吊材 5 6 7 () Young.65 4 N/mm Young 5 mm 6 (3) 7) 7-64-
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3 ( f = 6 ) 5 J7 ( f =.5 ) 4 ( f = ) f =.4 S6 kn S S 3..6 S S. 4. S3 S3 3..4 S4 S4 5 43. S5 S5 74. 77. S6 6.. S7 S7 73. 75.4 S S 5.7 46. S S.7 5.4 J J J J 7.6 53.5 6.6.7 f =. J5 J7 J6 f =.5 J5 J7-67-
荷重パラメータ f 軸力 [kn] 軸力 [kn] 3 J J J J J J3 J3 J4 J4 J5 J5 J6 J6 J7 J7 J アーチリブの位置 J J Case Case Case3 Case4 Case5 J J 6 3 J J J J J J3 J3 J4 J4 J5 J5 J6 J6 J7 J7 J アーチリブの位置 J J Case Case Case3 Case4 Case5 J J 7 ピン結合モデル ( 床版あり ) ピン結合モデル ( 床版なし ) 4 6 相当塑性ひずみ % 4 % 3 % 3 4 % S6 S6 f =. S S S S S6 S6 S6 S6 3.3 % f c f c 33 f c -6-
荷重パラメータ fc.5 5 荷重パラメータ fc.5 5 ピン結合モデル ( 床版あり ) ピン結合モデル ( 床版なし ) S S S3 S4 S5 S6 S7 S S ピン結合モデル ( 床版あり ) ピン結合モデル ( 床版なし ) S S S3 S4 S5 S6 S7 S S 破断想定部材 破断想定部材 f c 3 f c 4 荷重パラメータ fc.5 5 荷重パラメータ fc.5 5 ピン結合モデル ( 床版あり ) ピン結合モデル ( 床版なし ) S S S3 S4 S5 S6 S7 S S 破断想定部材 ピン結合モデル ( 床版あり ) ピン結合モデル ( 床版なし ) S S S3 S4 S5 S6 S7 S S 破断想定部材 3 f c 33 f c 5 荷重パラメータ fc.5 5 ピン結合モデル ( 床版あり ) 破断想定部材 ピン結合モデル ( 床版なし ) S S S3 S4 S5 S6 S7 S S 3 f c 3 S S f c p 6, 7 Romeijn and Bouras 3) 4) f c S5 f c 33 f c S5 3 3 S4 f c 3 f c S f c f c S5 p 4 p p p -6-
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