Construction Of A Two-span Self-anchored Suspension Bridge With Single Tower

Self-anchored suspension bridges are increasingly appreciated by engineers for their merits such as aesthetic appearance and high adaptability to the land form and geology.It has become a more competitive design scheme in middle-,and small-span in cities.Based on two-span self-anchored suspension bridge construction control,this paper studies the theory and method of self-anchored suspension bridge construction control.The main content covers the following aspects:(1) This paper studies the calculation theory and method,including initial elastic theory and finite displacement theory at present.Main cable force figure can be simplified as flexible cable with even load and focus force at the hanger,so main cable is more precise seen as segmental catenary than seen as parabola.Main cable configuration of completed bridge is calculated by segmental catenary theory,and the free length of each main cable,the hanger length,free main cable configuration,the saddle pre-offset are also calculated,and the position of each rope clip is determined.No passage is adopt in main cable construction.So money and time is in advance.The influence of error factors such as cable length change, temperature change to the main cable erection configuration,so the precision is much higher.(2) Hanger of self-anchored suspension bridges must be stretched many times because of many factors such as load-beating of structure.For the complicated nonlinear process of tensioning hangers,considering many nonlinear factors,such as the concrete shrinkage and creep,pre-stressing loss,etc.With making use of the finite element program,the paper studies the construction process,in the pouring part of beam and stretching all the tension,leading to the first pouring of concrete longitudinal compressive stress is too large,how to implement the tension to bridge state.(3) The saddle displacement on the top of the tower,the stress of the tower bottom and the main girder control section,the main cable configuration and the hanger force are observed and measured,and all the data should be analyzed and compared with the calculation data after every tension in order to guide the next tension.So the key problem of system transition in construction control of self-anchored suspension bridge is solved.It has some important reference value to the same bridges.