岸坡淤积对高桩码头结构受力的影响及清淤防治措施

The impact of sediment accumulation on the structural stress of high-pile wharf and sediment removal measures

利用有限元方法分析了岸坡淤积对高桩码头结构受力的影响,提出了码头下方局部清淤联合码头后方开挖以减小淤积影响的防治措施。通过构建高桩码头排架结构的实体单元模型,探讨了岸坡淤积和使用荷载的耦合作用对码头结构内力及水平位移的影响;通过比较岸坡淤积过程中的桩基受力及变形,揭示了桩基损伤机理,即岸坡淤积使桩土相互作用面积增大,桩基受到的附加淤积土压力作用增大,导致受横梁约束桩基的桩顶弯矩增大。岸坡淤积对码头结构存在显著影响,随着淤积高度的增加,桩基的内力及水平位移、横梁的水平位移显著增大;码头岸坡淤积、码头后方超淤及船舶撞击力的联合作用,对淤积岸坡的坡顶处和后侧的向岸斜桩的内力影响最大,桩基最易受损;对码头下方的淤积坡肩进行局部清淤,联合在码头后方挖槽的清淤措施,可有效降低危险桩基的桩顶弯矩,减小淤积对码头结构的影响。

This study employs the finite element method to analyze the impact of sediment accumulation along riverbanks on the structural stress of high-pile wharves and proposes mitigation measures,including localized dredging beneath the wharf combined with excavation behind the wharf to reduce the effects of sedimentation.A solid element model of a high-pile wharf bent structure was constructed to explore the coupled effects of sediment accumulation and operational loads on the internal forces and horizontal displacement of the wharf structure.By comparing the stress and deformation of pile foundations during the sedimentation process,the study reveals the damage mechanism of the pile foundation,where sediment accumulation increases the interaction area between the pile and soil,resulting in greater additional pressure from the sediment on the pile.This leads to an increase in the pile top moment constrained by the beam.Sediment accumulation has a significant impact on the wharf structure,as the internal forces and horizontal displacement of the pile foundation and the horizontal displacement of the beam increase markedly with the height of the sediment.The combined effect of sediment accumulation at the riverbank,excessive sedimentation behind the wharf,and ship impact forces exerts the greatest influence on the internal forces of inclined piles near the top and rear of the sediment slope,making the pile foundation more susceptible to damage.Localized dredging of the sediment slope shoulder beneath the wharf,combined with excavation behind the wharf,effectively reduces the pile top moment of critical piles and mitigates the impact of sediment accumulation on the wharf structure.