Key Construction Technology for Steel Sheet Pile Cofferdam and Embedded Pile Cap of Tuojiang River Bridge
Tuojiang River Bridge on Jintang-Jianyang-Renshou Expressway has a total length of 963m,and the main bridge is a space curve single pylon cable-stayed bridge with twisted cable planes.The overburden at the bridge site is a thin layer of pebbles.The underlying stratum consists of high-strength moderately weathered siltstone and sandy mudstone.The main pile cap is a mass concrete structure which is buried below the riverbed surface.In order to overcome the construction problems of traditional cofferdams under such engineering conditions,a new type of composite cofferdam solution of"steel sheet pile+rock wall"was proposed.To ensure that the socket length of the steel sheet piles was greater than 10m and the perpendicularity deviation was less than 0.5%,the guide hole technology supported by full casing was adopted.Meanwhile,to ensure the anchoring stability and watertightness of the cofferdam,the water sealing technology by backfilling sand and grouting was adopted.During the construction of the main pile cap,the pouring quality for the mass concrete was ensured by the comprehensive temperature control technical measures.The monitoring results show that the control indexes,including the cofferdam deformation,internal bracing stress and concrete temperature difference,are within a reasonable range.The safety,efficiency and quality assurance are achieved for the super-large bridge foundation construction.
NETL
NSTL
万方数据
维普
