振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2014年
1期
176-182,208
,共8页
蝶形拱桥%冲击系数%车桥耦合振动%钢管混凝土
蝶形拱橋%遲擊繫數%車橋耦閤振動%鋼管混凝土
접형공교%충격계수%차교우합진동%강관혼응토
butterfly-shaped arch bridge%impact factor%vehicle-bridge coupled vibration%concrete-filled steel tube
通过建立车桥耦合动力学模型,编写计算程序研究了行车速度、偏载距离、结构阻尼、路面不平度、行车方向、轴距、车间距、车辆数及结构设计参数等对蝶形拱桥各构件动力冲击系数的影响。结果表明:主吊索力的冲击系数整体上随着速度的增大而增大;偏载侧主拱拱顶横向位移的冲击系数随着偏载距离的增大迅速增大,而竖向位移的冲击系数却呈现迅速下降的趋势;阻尼比使得各构件的冲击系数均有所降低;构件的冲击系数随着路面不平度等级的不同而不同;异向行驶时,左右对称的各构件冲击系数差别较大;存在某个矢跨比值使得主梁跨中挠度的冲击系数最小;采用尼尔森体系,各构件的冲击系数明显减小。
通過建立車橋耦閤動力學模型,編寫計算程序研究瞭行車速度、偏載距離、結構阻尼、路麵不平度、行車方嚮、軸距、車間距、車輛數及結構設計參數等對蝶形拱橋各構件動力遲擊繫數的影響。結果錶明:主弔索力的遲擊繫數整體上隨著速度的增大而增大;偏載側主拱拱頂橫嚮位移的遲擊繫數隨著偏載距離的增大迅速增大,而豎嚮位移的遲擊繫數卻呈現迅速下降的趨勢;阻尼比使得各構件的遲擊繫數均有所降低;構件的遲擊繫數隨著路麵不平度等級的不同而不同;異嚮行駛時,左右對稱的各構件遲擊繫數差彆較大;存在某箇矢跨比值使得主樑跨中撓度的遲擊繫數最小;採用尼爾森體繫,各構件的遲擊繫數明顯減小。
통과건립차교우합동역학모형,편사계산정서연구료행차속도、편재거리、결구조니、로면불평도、행차방향、축거、차간거、차량수급결구설계삼수등대접형공교각구건동력충격계수적영향。결과표명:주조색력적충격계수정체상수착속도적증대이증대;편재측주공공정횡향위이적충격계수수착편재거리적증대신속증대,이수향위이적충격계수각정현신속하강적추세;조니비사득각구건적충격계수균유소강저;구건적충격계수수착로면불평도등급적불동이불동;이향행사시,좌우대칭적각구건충격계수차별교대;존재모개시과비치사득주량과중뇨도적충격계수최소;채용니이삼체계,각구건적충격계수명현감소。
On the basis of the dynamic model of vehicle-bridge coupled vibration,the influencial parameters on the impact factor of each member in butterfly-shaped arch bridge were studied by a self-compiled computing program,such as the velocity of vehicle,distance of eccentric load,structural damping,road roughness,traffic direction,wheelbase, vehicle-to-vehicle distance,vehicle number and structural design parameters.The results show that:as a whole,the impact factors of main cable forces will increase with the increase of vehicle velocity;the impact factor of transverse displacement at the vault of major arch ribs on eccentric side will increase with the increase of the distance of eccentric load,however,the impact factor of vertical displacement will decrease rapidly;the increment of the structure damping will make the impact effect weakened;the impact factor varies along with the grade of road roughness;there is great difference between the impact factors of symmetric members when the driving direction is different;there is an optimum rise/span ratio that minimizes the impact factor of mid-span deflection;the impact factors will be reduced obviously when the Nielsen system is used.