强震作用下风电塔损伤特征与振动台试验研究

Study on the damage feature and the shaking table model test of wind turbine tower under the action of earthquake

基于某轮毂高度为86 m的海上风电塔结构,考虑"叶片-轮毂-塔筒-桩"的精细化有限元模型,研究了考虑桩土作用时近远场地震动和不同加速度峰值对风电塔结构的非线性动力响应影响规律。为了验证有限元模拟的正确性进行了室内模型振动台试验研究,验证所建模型和数值模拟方法的正确性。研究结果表明:远场地震动对风电塔这种高耸柔性结构的动力响应影响最大,对其塑性极限状态极限值起着控制作用;由于受到偏心荷载作用,结构最薄弱部位位于结构的7/8左右高度处,此截面处应力和加速度随着地震动加速度峰值的增大而增大,首先进入塑性阶段;在弹性范围内,结构各部位的加速度响应峰值成几何倍数增长,与振动台实验得到的结果相吻合,验证了所建模型和数值模拟方法的正确性。

Based on an offshore wind turbine tower with the hub height of 86 m, considering the refined finite element model of ＂blade-hub-tower drum-pile＂, we studied the seismic dynamic responses of the structure under different seismic loads and the acceleration was studied when considering the soil and pile interaction. In order to verify the correctness of the model and numerical simulation method, a shaking table model test has been done. It is shown that far field earthquake has a greater influence on this kind of structure, it plays a controlling role on plastic limit value. The weakest area is located at the 7/8 height of the structure. The plastic stage will appear firstly at the area with the increase of the seismic acceleration. The peak acceleration response of each part of the structure is increased linearly. It is similar with the test results. This verifies the correctness of the model and numerical simulation.