叉桩布置对高桩码头地震动力反应的影响

Seismic performance of the pile-supported wharf with varied batter pile patterns

为了解叉桩对码头抗震性能的影响作用,建立高桩码头结构动力有限元模型,以全直桩高桩码头、美国Okland港第七街高桩码头和霍华德高桩码头为算例,研究全直桩码头、叉桩承台码头、叉桩置于全直桩码头后方这三种码头结构型式的地震反应,在此基础上提出设计建议。分析结果表明,全直桩码头结构柔度大,延性好,内力分配相对均匀,可通过大变形吸收地震能量,抗震性能较好;叉桩置于码头承台时,码头结构刚度相对较大,使叉桩节点易于发生破坏;叉桩置于全直桩码头后方时,叉桩可阻挡部分地震波的传播,降低码头结构刚度,减小码头桩周土弱化程度,全直桩码头结构的抗震性能显著提高。

Recent researches have highlighted that batter piles might cause damage to pile-supported wharf during a violent earthquake, however, according to the performance of the batter piles in the 7th street Marine Terminal and the Howard Marine Terminal of Oakland outer harbor in 1989 Loma Prieta earthquake, it may not be true. In order to better understand the seismic performance of plumb pile system, batter pile system and plumb pile system with independent batter piles in the rear, the dynamic time history analysis was implemented for those three marine termi- nals. The analysis results indicate that, the plumb pile system could decrease earthquake energy through large de- formations to reduce the damage risk ; the batter pi pendent batter piles were in the rear of plumb pile waves, which could reduce seismic effects, so the le system might be damaged by the batter system, the batter piles would disturb the seismic performance of plumb pile system piles; while the inde- propagation of seismic could be better here.