Research And Optimization On Compound Structures Of Open Style Offshore Deep-water Wharf

Our country is to a certain extent short of resources, with the high and continually development of the national economy, the requirement for the non-renewable resources especially petroleum is stronger than before. To complete this kind of long distance marine transport of major bulks, the use of ultra-large type vessels is obviously economical. Then, it's extremely urgent to build new deep-water wharfs that suit to the vessels.Pile-gravity type complex structure is a new and promising structure of open style offshore deep-water Wharf. But now it still doesn't form skilled technology in our country. This paper is combined with 300 thousand DWT crude oil terminal project in Dalian New Port. The pile-gravity type complex structure is chosen for the researching object. And this paper calculates and checks the whole structure owing to the physical condition and operating requirements. The main calculation includes: loads, stability of the whole structure, the bearing capacity of the piles and the stress between the pile and the caisson. After the calculation, methods suited for this kind of structure are summarized. According to the result, the original plan is optimized, and finally a safe and applied plan is afforded to support the actual project.Based on the actual project, the vertical pile and spur pile structure are studied separately. More general formulas and methods are proposed, and the optimization principles and referenced types are summarized for the pile-gravity type complex structure where the depth of water is larger than 25m. The study on the vertical pile structure includes: discipline for the size optimization of caisson and the recommend size, the formula and method to definite the demarcation point between pile and caisson, the recommend size for piles and the changing discipline of the stress and the changing discipline of the bearing capacity of the node. The study on the spur pile structure includes: discipline for the size optimization of caisson and the recommend size, the changing discipline of the pile stress and the comparison between the vertical pile plan and the spur pile plan. At last, the problems and the future development of this structure type are also discussed. Achievements from the study can guide the design of the complex structure deep-water wharf.New wharf structure type studied in the paper can be extensively applied for large open style wharf instead of gravity type caisson berth and long pile wharf. The new structure type is propitious for further expansion of port construction in our country and can enhance economic performance obviously.