Characteristics And Stability Analysis Of Floating Construction Drilling Platform

The bridge construction becomes more and more difficult with the depth of water.In the construction of bridge in deep water,the large diameter bored pile is used as the Pier foundation of the bridge,and it is easy to be restricted by the change of water-level,wave and navigation in the construction,so it is necessary to set up temporary construction platform to eliminate the construction interference and to solve the problem of precise positioning.In deeper waters,using conventional fixed platform as construction platform has long construction period,high project cost and great impact on environment,and the floating platform assembling and erecting is simple,can shorten the construction period,the impact on water level change and depth is small,but it is influenced by wind wave force and flow force greatly.This paper takes the Longhu bridge in Fujian Cotton Beach Reservoir area as the construction background,aiming at the particularity that the water depth of the Cotton Beach reservoir is more than 70 meters and the bare granite topography condition,the large lifting equipment cannot enter the construction site.Under the premise of simply using a fixed or a floating construction platform construction platform,has been unable to meet the construction requirements for floating platform with a combination of fixed platform drilling platform construction research.First,understand the deep waters of bridge construction at home and abroad,the group pile foundation construction process of research and development platform,comparing the advantages and disadvantages of the fixed construction platform and the floating construction platform as the construction platform,the static analysis of floating construction platform and the method of adjusting its displacement should be studied more comprehensively.Secondly,using the method of theoretical calculation,the calculation and analysis of the floating construction platform of Longhu Bridge in five kinds of different working conditions in the process of locating pile steel casing by the action of wind load,wave load,water force and anchor rope pulling force,the Anti-overturning stability of floating platform and the inclination of floating platform moving orbit are analyzed and checked.Thirdly,the calculation formula of the force and displacement of the single anchorage system of the floating construction platform is deduced,the calculation formula of the anchor rope shrinkage and floating platform displacement of the anchorage system is deduced and optimized,the actual amount of the anchor rope of the Longhu bridge is contrasted with the theoretical calculation value,and the influencing factors of anchor system are analyzed.Finally,the Midas Civil modeling software is used to establish the mechanical model for the drilling platform composed of fixed platform and floating platform,and the whole and local elastic stability of the whole construction drilling platform is analyzed.