海上振动沉管碎石桩施工关键技术

舟山市岱山县大小鱼山促淤围涂项目大桥接线成陆工程采用斜坡堤结构,地基处理采用塑料排水板和振动沉管碎石桩2种形式,其中振动沉管碎石桩全部为水上施工,是国内港航工程至今应用的桩长最长的振动沉管碎石桩。针对海上振动沉管碎石桩施工技术难点,通过改造打桩船、优化桩位布置、制定有效的质量保证措施以及碎石出运监控措施,解决了设备功效低、定位慢、定位精度差、碎石拒落、灌量不足、密实度差等一系列难题,形成一套海上振动沉管碎石桩施工关键技术。

Key construction technology for marine vibrating sinking-pipe macadam pile

The bridge connection and landing project of Daxiaoyu hill reclamation project in Daishan County,Zhoushan City adopts sloping breakwater structure,and the foundation treatment adopts two types:plastic drainage board and vibrating sinking-pipe macadam pile,among which,vibrating sinking-pipe macadam piles are all constructed on the sea,which is the longest vibrating sunken pipe gravel pile applied to the domestic port and waterway engineering up to now.A set of key technologies for the gravel piles construction involving the marine vibro- pipe-sinking installation is established against the technical difficulties previously faced during construction by making necessary modifications on the pile-driving barges,optimizing the pile layout,working out a set of effective quality assurance measures and monitoring measures for gravel delivery,effectively solving a series of difficulties such as low equipment operational efficiency,slow positioning,poor positioning precision,non-sinking gravels,insufficient grouting,and poor compactness.