In recent years, with the rapid development of water transportation in China, the old terminal facilities have become increasingly unsuitable for the development needs of ships. Such as low berthing level, inability to adapt to changes in cargo types, low utilization rate of shoreline resources, insufficient terminal capacity, etc. In order to further improve the port function and adapt to the new development needs, the existing code head structure needs to be reinforced and modified accordingly.

1 Characteristics and classification of the reinforcement and reconstruction of the wharf structure

Through the investigation and comparative analysis of hundreds of domestic and foreign code head reinforcement and transformation projects, it is concluded that the code head structure reinforcement and transformation has the following characteristics.

1) Reinforcement of wharf structure is the main way of wharf construction in today's world.

Countries such as Europe and the United States have experienced the construction of new terminals, the coexistence of new construction and reinforcement and reconstruction, as well as the development process of terminal construction with emphasis on reinforcement and reconstruction. Wharf structure reinforcement and transformation technology has become mature. Although China's large-scale code head reinforcement transformation has just begun in recent years, there have been many very successful cases.

2) The purpose of strengthening and reconstructing domestic and foreign wharf structures is the same.

The structural reinforcement of domestic and foreign terminals is to adapt to the size of the ship, to adapt to the loading and unloading of new cargoes, restore or improve the structural function

3) The technical methods for the reinforcement and transformation of the wharf structure are diverse.

Due to the variety of terminal structure types, diversified cargo types, and diversified industry requirements, the technical methods for strengthening and rebuilding the terminal structure are also diverse.

The key technical classifications of the reinforcement and reconstruction of the wharf structure are as follows:

① Reinforcement and transformation technology of high-pile wharf structure;

② Reinforcement and reconstruction technology of gravity dock structure;

③ Reinforcement and transformation technology of sheet pile wharf structure;

④ The key construction technology of wharf structure reinforcement and transformation.

2 Key technologies of wharf reinforcement

1) The engineering methods for the reinforcement and reconstruction of high-pile wharves mainly include the split pier and abutment method, local reinforcement method, sheet pile reinforcement method, front pile and abutment method, expanded fender method, etc. or a combination of the above methods.

2) Gravity wharf structure reinforcement and transformation engineering methods mainly include pile-pile method in front of wall, pier-abutment method in front of wall, expanded fender method, foundation bed grouting method, wall grouting method, breast wall expansion method, and foundation treatment method behind wall, decompression platform method behind the wall, etc. or a combination of the above methods.

3) Reinforcement and reconstruction engineering methods of sheet pile yard head structure mainly include pile-in-wall method, pier-in-wall method, foundation reinforcement method behind wall, newly-built sheet pile method, pressure-reducing bearing platform method in wall, behind the wall half curtain or curtain pile method, adjusting anchorage installation method, etc. or the above combination method.

4) Vibration-free linear cutting technology involved in wharf reinforcement and reconstruction projects, pneumatic dredging technology at the yard head, piling technology on the land of the wharf, grouting technology on the foundation bed, non-destructive penetration of caissons or deep hole-throwing (sand) site-forming holes, etc.