S形非规则高架曲线桥梁振动台试验研究

SHAKING TABLE TEST OF S-SHAPED IRREGULAR CURVE VIADUCT

为研究S形非规则高架曲线桥梁在地震作用下的抗震性能,制作一座相似比为1/20的模型桥梁,对该模型桥梁测试过程的试验现象、动力特性、加速度及位移测试数据进行详细分析研究。结果表明:S形曲线桥梁在整个测试过程中结构自振频率下降明显,阻尼比显著增大;多遇地震输入时墩底加速度峰值小于墩顶加速度峰值,罕遇地震输入时,由于墩梁扭转十分严重,导致墩顶加速度峰值小于墩底加速度峰值;多遇地震时,墩梁径向相对位移大于切向相对位移,罕遇地震作用下,墩梁径向相对位移小于切向相对位移。

In order to study the seismic performance of a S-shaped irregular elevated curve bridge under earthquake,a Sshaped curve bridge model with the similar ratio being 1 /20 was designed and produced,to analyze the experimental phenomena,the dynamic characteristics,acceleration and displacement test data of the model bridge in the processes of tests. The results showed that the S-shaped curve bridge during the whole test process,the self vibration frequency of the structure decreased significantly and the damping ratio increased significantly. The peak acceleration on the bottom of the pier was less than that on the top of the pier under frequent earthquakes; the peak acceleration on the bottom of the pier was larger than that on the top of the pier due to very serious torsion of pier beam under rare earthquakes. Pier beam radial relative displacement was larger than the relative tangential displacement in frequent earthquakes; pier beam radial relative displacement was less than the relative tangential displacement in rare earthquakes.