Study On Structural Ice-resistant Performance For The Bridges Of Deepwater Area In Bohai Sea

The Bohai Sea is an inland sea area of China,which is adjacent to the economically developed Beijing-Tianjin region in the west and the less developed northeast region in the east.However,the space restrictions in the Bohai Sea area causes the problems of long shipping time and long distance of land transportation between the two places,which affected the economic interaction between the two places.Therefore,it is particularly necessary to build a maritime transport project that connects the two banks across the Bohai Sea.The proposed Qin-Da Sea-crossing Channel Project is located between Qinhuangdao City and Dalian City,which is used to connect the Bohai sea area to solve the problems of poor communication connection conditions and big economic development gap in the two places.However,there are still many difficulties in the construction of the project.Ice load is one of the severe challenges facing the project.In the proposed Qin-Da Sea-crossing Project,non-navigation-hole bridge accounts for more than 80%of the total project scale.This part of bridge is sensitive to dynamic ice load disturbances.In addition,the latitude of the Bohai sea is high.It is the ice area with the most severe ice conditions in China,which has an annual icing period of about 3⁴ months in the winter.The harsh ice environment poses a great threat to the structures in the sea area.It is necessary to carry out adequate anti-ice research work.In view of the above-mentioned problems,this paper takes the proposed Qin-Da Sea-crossing Project as its research background and uses finite element numerical simulation methods to study the performance of ice resistance on bridge in the project.The main works are as follow:First,review the relevant literature on anti-icing research at home and abroad,summarize the main theoretical results of other people's anti-icing research and learn from others'anti-icing research methods to provide theoretical support for the anti-icing research work of the bridge;Second,summarize the research status of static ice loads at home and abroad and list some extreme static ice force calculation formulas when structures damaged by ice loading.Based on the calculations and analysis,suitable extreme static ice force calculation method for this project structure are obtained.Third,with reference to ISO 19906:2010 specification^[1]and IEC 61400-3:2009specification^[2]and combined with finite element numerical analysis method,the response law of key positions of the bridge under dynamic ice loading is obtained after the analysis of ice-induced vibration time-course response for selected bridge structures.Fourth,analyze and compare the effects of changes in pile length,ice thickness,soil conditions and the existence of wave forces on the ice-induced vibration of bridge structures,and conclude some problems that should be paid attention to.Fifth,some anti-icing measures are summarized for the current bridge structure.According to the actual situation of the bridge structure studied in this paper,a comprehensive anti-icing method suitable for this bridge is proposed.