纵肋-横隔板弧形切口应力响应的面外特征研究

STRESS CHARACTERISTICS OF OUT-OF-PLANE DISTORTION AROUND DIAPHRAGM CUTOUT AT RIB-DIAPHRAGM INTERSECTION

为获得正交异性钢桥面板横隔板弧形切口母材在典型轮载作用下的应力响应的面外特征,开展了随机车流下正交异性钢桥面板弧形切口应力监测和分析。研究表明:一辆卡车通过横隔板弧形切口将产生与轴组数量对应的应力幅,其应力响应不能分辨轴组内单轴;在超载卡车作用下横隔板弧形切口将产生很大的应力响应,应力峰值可能会大于钢材的容许应力,而此时弧形切口处于双向受压状态,活载应力幅为压应力幅;研究同时发现,横隔板会受到面外弯曲作用,靠纵肋-横隔板焊缝下端越近,其面外变形越大,产生的面外应力越大。

In order to obtain the stress characteristics of out-of-plane distortion on base metal around diaphragm cutout under typical wheel loadings,stress monitoring and analysis were carried out on diaphragm cutout detail at orthotropic steel bridge decks under random traffic flows. The research shows that one truck passage produces stress cycles which are the same as the number of truck axle groups,while individual axles among an axle group can not be indentified based on stress records. High stress peak on the diaphragm cutout,which may beyond the steel allowable strength,could appear under overweight trucks,and at this moment the diaphragm cutout is under bi-axle compressive state which presents compressive stress range. The research also found that the diaphragm cutouts at rib-diaphragm intersection were undergoing significant out-of-plane distortion,and the level of the distortion is gradually high close to the low end of rib-diaphragm welding with increased stress value.