The Study Of Finite-element Analysis To The Steel Lifting Caisson In Deep-water Foundation

With the development of construction technology and mechanic about deep-water foundation, the steel lifting caisson had being applied widely for construction of high pile cap. In this thesis, on the basis of the existing construction and design data in the world, as an example of Ma'anshan Changjiang River Highway Bridge, the author makes a review and summary of the steel lifting caisson construction method, introduces design and construction process of the steel lifting caisson of the middle tower's foundation below the left primary bridge in Ma'anshan Changjiang River Highway Bridge in detail.The paper introduces finite-element software, MIDAS/Civil, by which the author can build overall model about the steel lifting caisson of Ma'anshan Changjiang River Highway Bridge, and gives a comparatively accurate simulation of six loadcases, which include loadcase floating state of the steel lifting caisson, loadcase sinking to the steel lifting caisson's shoes, loadcase moulding enclosed concrete, loadcase pumping water, loadcase moulding the first cap concrete for 3.5 meter, loadcase moulding the second cap concrete after removing all the underprop. The author calculates stress and distortion of the steel lifting caisson when loads exerted in primary beams of the bottom board, the level ring plates, the bottom board, the wall board, the level inclined underprops of the wall board, the underpropped truss. The results of calculation accord with the structural strength and stiffness requirements. Study in the thesis indicates finite-element method is significant for the calculation of construction structure in the reality.