铁道标准设计
鐵道標準設計
철도표준설계
RAILWAY STANDARD DESIGN
2014年
6期
58-60,61
,共4页
铁路桥%连续梁%地基柔性效应%弹塑性%地震反应
鐵路橋%連續樑%地基柔性效應%彈塑性%地震反應
철로교%련속량%지기유성효응%탄소성%지진반응
railway bridge%continuous girder%subsoil flexibility effect%elastic-plastic%seismic response
以某高速铁路大跨连续梁桥固定墩纵桥向的弹塑性地震反应为研究对象,建立考虑地基柔性约束效应的单墩动力计算模型,分析地基柔性效应对桥墩动力特性及弹塑性地震反应的影响规律。结果表明:地基比例系数m值的改变对桥墩的1阶自振频率影响较明显;随着地基比例系数m值的降低,墩顶位移及基底位移逐渐增加;地基越软,桥墩的弹塑性地震反应有增大的趋势。为了更加合理的描述桥墩的塑性状态,建议对软土场地桩基础钢筋混凝土桥墩进行延性抗震设计时,优选墩底曲率延性指标进行评价。
以某高速鐵路大跨連續樑橋固定墩縱橋嚮的彈塑性地震反應為研究對象,建立攷慮地基柔性約束效應的單墩動力計算模型,分析地基柔性效應對橋墩動力特性及彈塑性地震反應的影響規律。結果錶明:地基比例繫數m值的改變對橋墩的1階自振頻率影響較明顯;隨著地基比例繫數m值的降低,墩頂位移及基底位移逐漸增加;地基越軟,橋墩的彈塑性地震反應有增大的趨勢。為瞭更加閤理的描述橋墩的塑性狀態,建議對軟土場地樁基礎鋼觔混凝土橋墩進行延性抗震設計時,優選墩底麯率延性指標進行評價。
이모고속철로대과련속량교고정돈종교향적탄소성지진반응위연구대상,건립고필지기유성약속효응적단돈동력계산모형,분석지기유성효응대교돈동력특성급탄소성지진반응적영향규률。결과표명:지기비례계수m치적개변대교돈적1계자진빈솔영향교명현;수착지기비례계수m치적강저,돈정위이급기저위이축점증가;지기월연,교돈적탄소성지진반응유증대적추세。위료경가합리적묘술교돈적소성상태,건의대연토장지장기출강근혼응토교돈진행연성항진설계시,우선돈저곡솔연성지표진행평개。
This study took the fixed pier of a long-span continuous girder bridge on high-speed railway as the research object, in order to ascertain the fixed pier's elastic-plastic seismic response in bridge's longitudinal direction. Thus, a dynamic calculation model of single pier considering the subsoil flexibility effect was established, and the influence on the bridge pier's dynamic characteristic and elastic-plastic seismic response caused by subsoil flexibility was researched. The results show:the change of the subsoil scale factor m has obvious influence on the first-order natural frequency of vibration; the pier top and foundation bottom displacements will increase gradually as the subsoil scale factor m decreases;the softer the subsoil is, the bigger the elastic-plastic seismic response of the bridge pier will be. Therefore, it is suggested in this study that the curvature ductility index of bridge pier bottom should has the first priority to be chosen when carrying out the seismic ductility design for reinforced concrete bridge pier with pile foundation in soft subsoil site, so as to reflect the plastic state of bridge pier more reasonably.