To optimize the multi-batch prefabricated dry dock closure scheme of inland river immersed tun-nel,a semi-gravity dock gate block & steel dock gate closure system was proposed based on a typical immersed tube tunnel dry dock on soft soil foundation in Guangzhou,and the economic and rational comparison was made with the dock gate cofferdam closure scheme.A 3D model was established based on numerical software to reveal the mechanical mechanism of lattice dock gate block,and the sensitive factors such as joint type,wall thickness and dock gate block length were discussed.The results show that the cost of the semi-gravity dock gate block &steel dock gate closure scheme is 20％lower than that of the multi-batch prefabricated inland river immersed tunnel,and the construction period is also reduced by half a year.The lattice dock gate block shows the similar characteristics as bidirectional plate,in which the bearing force is mainly in horizontal direction.The rigid joint dock gate block has strong overall cooperative force capacity and the flexible joint dock gate block also has good overall cooperative force capacity under the constraint of the top cover of the wall,but the amplitude and shape of their displacement and bending moment are different.With the wall thickness increases,the wall bending moment increases but the wall displacement decreases.With the length of dock gate block increase,both the wall bending moment and displacement decrease.
Immersed tunnelDry dockDry dock gate closureDock gate blockMechanical mechanism
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万方数据
