海上风机基础灌浆连接段抗震性能试验

Experimental Study on the Seismic Behavior of Grouted Connection of Offshore Wind Turbine Foundations

海上风机在使用期间可能会受到地震荷载的作用,因此需研究灌浆连接段在不同轴压比下受低周反复荷载作用的滞回性能。对3根不同轴压比的灌浆连接段试件进行低周反复加载试验,研究灌浆连接段试件在低周反复荷载下的破坏模式、滞回曲线、延性与耗能及强度与刚度衰减等抗震性能。试验结果表明:在低周反复荷载下灌浆连接段的最终破坏模式为底部钢管的鼓屈破坏,伴随着浆体不同程度的开裂和剪力键的压碎;灌浆连接段试件滞回曲线饱满,具有良好的耗能能力及延性;随着轴压比的增大,灌浆连接段试件水平极限承载力下降,位移延性和耗能能力不断下降。

Offshore wind turbine in service may be subjected to seismic load, so it is necessary to analyze the hysteresis behavior of grouted connections with different axial compression ratios under low cyclic loading. An experiment was carried out on three grouted connection specimens with different axial compression ratios under cyclic load to study the failure patterns of the grouted connection specimens, in which seismic behaviors of hysteretic curves, energy dissipation, strength and stiffness degradation, as well as ductility of the specimens are analyzed. The result shows that the failure of the grouted connection accords with the level of grout fracture on the local buckling at the lower end of the outer tube. All grouted connection specimens exhibited favorable energy dissipation and ductility, even for the specimens under high axial load. The higher the axial compression increases, the lower the lateral ultimate strength of the grouted connection becomes. The ductility in displacement and the capacity of energy dissipation also decreases in such case.