液化场地高桩码头抗震性能地震动效应

为了研究地震动特性对液化场地高桩码头抗震性能的影响，本文依托高桩码头工程实例，建立了液化场地全直桩高桩码头地震反应分析数值模型，系统分析了地震作用下高桩码头的关键动力响应特征，确定了高桩码头各抗震性能需求指标，揭示了地震动特性对各抗震性能需求指标的影响规律。研究表明：地震作用下高桩码头桩基受弯、受剪和受压薄弱环节分别出现在持力层与上部粉质黏土层交界处、岸坡标高处和砂层与上部粉质黏土层交界处；峰值加速度、频谱特性和地震动输入方向均会显著影响高桩码头各项性能指标的抗震需求；高桩码头桩基的抗弯、抗剪和抗压性能需求分别由最靠陆侧桩桩顶处弯矩、各薄弱环节剪力和砂层与上部土层交界处轴力控制，抗震延性需求均由最靠海侧桩桩顶处水平位移需求控制。

Effects of Ground Motion Characteristics on Seismic Responses of Pile-Supported Wharf in Liquefiable Soils

In order to study the effect of ground motion characteristics on seismic performance of pile-supported wharf in liquefiable ground, a numerical model for seismic response analysis of pile-supported wharf with all-straight piles was established. The key dynamic response characteristics of pile-supported wharf under earthquakes were systematically analyzed, and the seismic performance demand indexes of pile-supported wharf were determined. The influence law of ground motion characteristics on seismic performance demand index was revealed. The results show that the weakness of bending, shear, and compression of pile foundation of pile-supported wharf occur at the junction of bearing layer and upper soil layer, bank elevation, and sand layer and upper soil layer, respectively. The peak acceleration, spectrum characteristics, and input direction of ground motion significantly affect the seismic demand of various performance indexes of pile-supported wharf. The flexural, shear, and compressive performance demand of pile-supported wharf are controlled by the bending moment at the top of the pile closest to the land side, the shear force of each weak link and the axial force at the junction of sand layer and upper soil layer, respectively. The seismic ductility demand is determined by the displacement demand at the top of the pile closest to the sea.