港珠澳大桥西人工岛钢圆筒及岛内回填砂成岛技术

港珠澳大桥西人工岛钢圆筒及副格围护结构振沉完成后，为确保其整体稳定性，采用定点、接力、分层抛填的方案对钢圆筒及副格内回填砂施工，有效控制了钢圆筒围护结构在回填砂施工期间的结构稳定性，防止了不利工况的出现。人工岛围闭前，采取设置龙口直接抛填以及泵送等方式进行水下回填；人工岛围闭后，采取水上抛填加陆上倒运的方案快速实现了人工岛陆域形成，为外海人工岛快速成岛积累了经验。

Technology of island formation by steel cylinder and backfill sand in west artificial island of Hong Kong-Zhuhai-Macau Bridge

To ensure the overall stability of steel cylinders and auxiliary grids after vibration and sinking of the artificial island wall steel cylinders and auxiliary grids of the Hong Kong-Zhuhai-Macao Bridge,we adopt the fixed-point,relay and layered backfilling schemes for the backfilling construction of steel cylinders and auxiliary grids,which can better control the structural safety of the steel cylinder enclosure structure during backfilling construction and prevent the appearance of adverse conditions.Before the enclosure of the artificial island,underwater backfilling is carried out by means of direct dump and pumping.After the enclosure of the artificial island,the land area of the east and west artificial islands of the Hong Kong-Zhuhai-Macao Bridge is quickly formed by means of the scheme of dump and backhaul on the road,which accumulates experience for the quick formation of the offshore artificial island.