以某高速公路项目为依托,针对变截面双柱排架墩进行抗震行为研究。结合混凝土用量及配筋原则,分别选取墩高相同的变截面双柱排架墩和等截面双柱排架墩进行Pushover分析。采用强度及位移延性两种指标对两种桥墩的抗震性能进行比较,并对不同高度变截面桥墩的抗震行为进行评价。此外还研究了中系梁布设位置及刚度变化对变截面双柱排架墩抗震行为的影响,并根据分析结果提出桥墩中系梁布设原则,对桥墩抗震设计具有一定的指导意义。 Based on a highway project, aiming at the seismic behavior of double-column mound pier with variable cross section. According to the amount of concrete and the principle of reinforcement, the pushover analysis of double-column mound pier with variable cross-section and double-column mound pier with equal cross section were selected respectively. The seismic performance of the two piers are compared by using two indexes of strength and displacement ductility, and the seismic behavior of piers with different heights is evaluated. In addition, the influence of the location and stiffness of the middle beam on the seismic behavior of the double-column mound pier with variable cross section is studied. According to the analysis results, the principle of the tie beam in the bridge piers is proposed, which is of guiding significance for the seismic design of the bridge piers.