Finite Element Analysis And Research On Large-scale Dock During Construction

For the efficient cost control of shipping and construction, major ships take dockyards into a completely new stage which is large scale and enlargement in recent years. Building docks, which are the soul of the construction of dockyards, the success of these projects are up to the structure design schemes, the project constructiont quality and rate. In this large-scale development process,some usual structures have been gradually replaced by revolutionary structures in building docks. To add a further refinement to improve and generalize,it is necessary to computational analysis field test in new structures. In recent years,the structural styles of wing wall and construction cofferdam are present to be diverse. Combined with practical work,this paper had carried on the analysis and research of anchor wall structure and new type construction cofferdam by using the finite element method. The main contents of this paper were listed as follows:(1) The development of modernized dry dock was introducd briefly,then the changes of the structural styles of wing wall and construction cofferdam were summarized.(2) The related concepts of finite element calculation were introduced in the dock engineering. The problems about structural types of dock walls and cofferdams were transformed into the mathematical problems which could be analysed by the computer and calculated with finite element method step by step in the construction period. The cell types, contact conditions,material constitutive relation and field variable model involved in this article were described.(3) According to the realities of the wing wall engineering in Qidong Fengshun dockyard,the correct construction procedure of anchor reinforced concrete wall was found,then the typical working conditions was determined. In order to find out the characteristics of deformation and force of the wing wall,the finite element calculating models were set up for typical working conditions respectively with the aid of the large-scale software MSC.MARC.(4) The scheme of monitoring spots location for the dockyard was arranged according to relevant specifications and the construction characteristics,and the important thing of monitoring was discussed. The practical datas of some typical monitoring spots in the wing wall were chosen to analyze,then the finite element calculation and measured data were compared. The results revealed the law of the basic mechanical behavior of which was caused by major working procedures and the degree of influences of prestressing force tension procedure about wing wall during construction period.(5) According to the actual situation of the cofferdam,the feasible designning plans were proposed. Considering of the cofferdam-type features,two-dimensional finite element models were built with finite element software AutoBank and saturation line,single wide seepage flow, exit gradient,critical slip surface and safety factor against sliding were calculated in the all types of cofferdam structure. Finally,the optimal type of cofferdam structure was confirmed by the ways of construction technology,economic investment, practical operation.