【摘要】 为了获得钢管高强混凝土拱桥的和振型特征，文中以某双跨拱桥为例，通过改变拱肋中混凝土强度、钢管厚度、径厚比等参数，分析其对钢管混凝土拱桥的刚度及自振频率的影响，明确混凝土强度及拱肋钢管厚度对固有频率及拱肋位移的影响规律。结果表明拱桥最大竖向振动频率与最大水平振动频率均小于人体感知范围，振动发生时并不会使人感觉到有明显的振感。拱肋、桥面系的平面内刚度大于平面外刚度，拱肋和桥面系的平面内弯曲变形出现的时间较晚。拱肋中混凝土强度的增加对拱肋刚度的提高并不明显。随着钢管厚度的增加，拱肋的延性和拱桥的竖向刚度逐渐提高，但钢管厚度过大会不利于拱桥的整体稳定性。钢管径厚比的增大有利于提高拱肋的平面外刚度及拱桥整体的竖向刚度。为进一步开展拱桥的动力响应分析奠定基础。更多还原

【Abstract】 In order to obtain the natural frequency and vibration mode characteristics of high-strength concrete filled steel tube arch bridge, a double-span arch bridge was taken as an example to carry out the modal analysis,and the first 10 natural frequencies and vibration modes of the structure were obtained. By changing the parameters of concrete strength, steel tube thickness, and diameter-thickness ratio in arch ribs, the influence of concrete strength and steel tube thickness on the stiffness and natural frequency of concrete filled steel tube arch bridge is analyzed. The influence law of concrete strength and steel tube thickness on the natural frequency and arch rib displacement is clarified. The results show that the maximum vertical vibration frequency and the maximum horizontal vibration frequency of the arch bridge are less than the perception range of human, and the vibration does not make people feel obvious vibration. The in-plane stiffness of arch rib and bridge deck system is larger than that of outplane stiffness, and the in-plane bending deformation of arch rib and bridge deck system occurs later. The increase of concrete strength is not obvious to the increase of arch rib stiffness. With the increase of steel tube thickness, the ductility of arch rib and the vertical stiffness of arch bridge gradually increase, but too large steel tube thickness is not conducive to the overall stability of arch bridge. The increase of diameter-thickness ratio of steel tube is conducive to improving the out-of-plane stiffness of arch ribs and the vertical stiffness of the whole arch bridge. The dynamic characteristic about arch bridge is also analyzed,which lays the foundation for further dynamic response analysis of arch bridge.更多还原