Application of Steel Sheet-pile Cofferdam in Construction of Bridge Pier in Water

Combining with the construction of piers in water of Suijiang bridge on Guiyang-Guangzhou railway using steel cofferdam,according to the actual stress state of steel sheet pile cofferdam,mechanic model is established,the steel sheet pile to be taken is designed,and the overturning resistance and slip resistance of steel sheet pile cofferdam are analyzed and calculated.Combined with the practical experience,the construction preparation of steel sheet pile cofferdam,the guide frame layout and steel sheet pile inserted construction technology process,the steel sheet pile construction quality control measures,measures of seepage prevention,construction monitoring method and steel sheet pile cofferdam demolition,etc are expounded.Among them,the following several aspects are summarized in detail,first,measures such as pile driving speed and verticality control,etc.are taken to ensure accurate folding of steel sheet pile in the process of steel sheet pile cofferdam construction;secondly,by using such measures as butter set within lock of steel sheet pile,plugging pipe set outside of steel sheet pile,drilling grouting outside the steel sheet pile which can not meet the design elevation,seepage from steel sheet piles is prevented;finally the dynamic monitoring method and the demolition method of steel sheet pile cofferdam are taken in the process of steel sheet pile construction.