超大直径单桩埋深对桩身变形的影响研究

Study on influence of depth of a single pile with large diameter on pile deformation

我国近海风电场建设多采用超大直径单桩基础,其在风、浪等水平荷载作用下产生较大侧向变形。为了研究桩基埋深对桩身变形的影响,按照1∶100的比例将原型缩小后,利用室内模型试验和有限元软件对此进行分析。结果表明:桩基埋深对桩身变形有较大影响。桩基埋深较浅时,表现出刚性桩特性,增加埋深可减小桩身变形,但桩基埋深达到7倍桩径后,继续增加埋深对桩身变形影响很小,据此认为桩基埋深达到临界深度,建议实际工程中单桩基础的埋深不要超过7倍的桩径。

The single pile foundation with large diameter is generally used in offshore wind turbines and larger lateral deformations are observed under wind and wave loads. To study the influence of the pile depth on the pile deformation, the indoor model test with a scale of 1: 100 and the finite element analysis are conducted. The results show that the pile depth has a great effect on pile deformations. When the pile depth is small, it exhibits the characteristics of a rigid pile. The deformations can be reduced by increasing the pile depth. However, if the pile depth reaches seven times the diameter, the deformations are seldom influenced by increasing the depth, which is defined as the critical pile depth. It is recommended that the pile depth should not exceed seven times the diameter in practical engineering.