岩基上双壁钢套箱围堰施工关键技术

Key Construction Technologies of Double Wall Steel Box Cofferdam on Rock Foundation

双壁钢套箱围堰主要应用于构(建)筑物水下基础的施工,用于管道接驳目前较少见。韶关市第三污水处理厂项目过江管道工程采用沉管+顶管组合方式跨越北江敷设,沉管、顶管在双壁钢套箱围堰内接驳,由于该围堰施工场地位于北江上游,大型浮吊船无法抵达现场,且围堰范围内没有施工的基础桩钢护筒可设沉放导向装置,面临吊装、定位对位、水下充填钢围堰壁仓等技术难题。通过研究应用岩基上双壁钢套箱围堰施工技术,钢围堰单节整体吊装,利用法兰板、高强螺栓进行节与节之间的连接,达到快速吊装与拆卸的目的,同时质量安全也得到了保证。

Double walled steel boxed cofferdams are mainly used for the construction of underwater foundations of structures,and are less commonly used for pipeline connections.The cross river pipeline project of the Third Wastewater Treatment Plant in Shaoguan City adopts a combination of sunken pipes and top pipes to be laid across the Beijiang River.The sunken pipes and top pipes are connected inside the double wall steel casing cofferdam.Due to the construction site of the cofferdam being located upstream of the Beijiang River,large floating cranes cannot reach the site,and the steel casing of the foundation piles that have not been constructed within the cofferdam area can be equipped with sinking guidance devices,facing technical difficulties such as lifting,positioning and alignment,and underwater filling of the steel cofferdam wall warehouse.By studying and applying the construction technology of double wall steel sleeve box cofferdam on rock foundation,the steel cofferdam is lifted as a whole in a single section,and flange plates and high-strength bolts are used to connect the sections,achieving the goal of rapid lifting and dismantling,while ensuring quality and safety.