曹妃甸煤码头起步工程钢板桩沉桩振动设备的选型与改造

Model Selection and Renovation of Vibratory Driving Equipment for Driving of Steel Sheet Piles for Initial Phase of Caofeidian Coal Terminal

码头前墙采用我国首创的大型H和AZ型组合钢板桩,需先穿过20 m厚的密实砂层后至设计标高,入泥32m左右。需要2 300 kN以上激振力的大型振动锤才能完成施工。在国内无厂家生产,外购又不能满足工期要求且价格昂贵的情况下,将2台APE400型液压振动锤进行改造,由原先振动壁厚250 mm钢筋混凝土大圆筒的夹具,改为振动厚度小于80 mm钢板的夹具,并重新设计制作了相应的过度梁,将5 468 t钢板桩振沉至设计标高,使新结构的使用在如此复杂恶劣的地质上成为可能。文章介绍了振动锤的选型和改造方法,可供类似工程参考。

Large composite steel sheet piles of H sheet pile and AZ sheet pile, which were originated in China, were used for the quay wall of the terminal. The composite piles were required to＇ first penetrate the 20 m thick dense sand and then be driven down to the design level, embedded in the soil for about 32 m. For this purpose, large vibratory hammers with an excitation force of more than 2 300 kN had to be used to complete the installation of the piles. Under the exigency that no domestic manufacturer could prodtice such large pile hammers, order from foreign manufacturers could not meet the construction period and the price were high, two APE400 hydraulic vibratory hammers were renovated and the clamps for reinforced concrete large diameter cylinders with walls of 250 mm thick were remade into clamps for steel sheet piles with a thickness of less than 80 mm. Transition beams were redesigned and fabricated. With the renovation, steel sheet piles of 5 468 t were driven down to the design level, thus making it possible to employ the new structure in complicated and inclement geological conditions. The paper describes the methods for selection of models and renovation of vibratory hammers for the reference of similar projects.