高墩连续刚构桥不同影响因素的地震响应分析

摘要

taking a continuous rigid frame bridge as the background,The finite element model of the main girder bridge pier pile foundation is established,The influence factors on the internal force and deformation of the bridge are analyzed,and the influence factors such as the height of bridge pier,the sec-tion of bridge pier,the distance between the piers and the piers of the bridge are analyzed.The results show that:in the 60 ~65 m range of bridge pier height,the bridge to the bridge is basically stable,and no longer decreases with the increase of the height of the pier;Increase of pier height increases the risk of peeling off the beam body,pier height of 100 m beam write cross section along the bridge to cross the bridge and to the displacement reached 139.1 ,97.5 mm;From the point of view of seismic resistance,the influence of circular section bridge piers on displacement is larger,the effect of hollow rectangular pier section and solid rectangular pier section on the internal force of pier is small,so the hollow pier is more economical;For the continuous rigid frame bridge,the reasonable distance between the double piers and thin wall piers can effectively reduce the force and displacement of the pier top,and can effectively im-prove the safety factor of the seismic action.%以某连续刚构桥为背景，建立了考虑主梁－桥墩－桩基－土层的有限元模型，分析了地震荷载作用下桥墩高度、桥墩截面、双肢薄壁墩间距等影响因素对桥梁典型截面内力及变形的影响。结果表明：在桥墩高度为60～65 m 范围内，中墩顺桥向剪力基本稳定，不再随桥墩高度的增加而递减；桥墩高度的增加增大了梁体脱落的风险，桥墩高度为100 m 时梁体中跨跨中截面顺桥向与横桥向位移达到139．1，97．5 mm；从抗震角度分析，圆形截面桥墩对位移影响较大，空心矩形桥墩截面与实心矩形桥墩截面形式对墩顶内力的影响不大，故空心墩较节约材料；对于文中连续刚构桥，合理的双肢薄壁墩间距能有效降低墩顶受力与梁体位移，能有效提高地震作用下的安全系数。