| With the development of economy,the road and railway construction is gradually deepened,and more and more construction work will involve crossing rivers and water bay.The extensive research work of deep water foundation is also carried out in this context.the key point of deep water foundation construction lies in how to construct underwater temporary facilities economically and reasonably,and steel sheet pile cofferdam is an extremely important form in all kinds of deep water foundations.Larson steel sheet pile has been widely used in pier cofferdam construction for its advantages of high strength,good impermeability,convenient construction,reusability,low cost and strong operability.This paper takes the cofferdam of No.4 pier of wufengshan Yangtze river bridge as the research background,and makes a reasonable construction scheme for the cofferdam construction by fully understanding the engineering background information.Practical construction schemes are put forward from the following six aspects: preparatory work before the cofferdam insertion construction,insertion construction,steel sheet pile closure,foundation pit excavation,installation of internal support system and construction of foundation pit monitoring,which provides reference for the formulation of steel sheet pile construction technology in the future.Combining with the actual construction situation,this paper selects four main construction conditions to conduct MIDAS analysis.The analysis results show that the deformation,principal stress and shear stress of steel sheet pile,inner support,ring beam and back cover concrete meet the specification requirements under these four working conditions,and the degree of foundation pit uplift is within a reasonable range.Theoretically,the safety of cofferdam construction is ensured.The chopper software based on rhino platform can realize parametric modeling,making up for the defect that MIDAS is not good at modeling,especially the ability to modify the model repeatedly after it is established,effectively making up for the shortcomings of MIDAS.Chapter six describes in detail how to set up a parameterized cofferdam model by using the clipper battery block diagram,and how to decompose the model into MCT files that MIDAS can recognize by using python scripting language.At the end of this article,two python battery block codes are attached,which is also the core part of this parametric modeling.researchers who need to realize the functions described in this article can directly adopt this code content.I hope I can make some contributions to the future research work of MIDAS. |
