Research on a Smart External Prestressed Bridge with Position-Adjustable Saddles

摘要

This paper is based on such a widely accepted concept that if the equivalent load of prestressing balances the applied load,the beam structure would have no deflections.Though there are many factors generating deflections,it is still feasible to control the bridge deformation by regulating the magnitude and distribution of equivalent action of external tendons.In the numerical example,the regulating procedure could be easily realized by setting a series of length-adjustable bars as the saddles of externally prestressed bridge.When the length of these bars varied to some rules,both the configuration and tension of the cable would be affected and vary remarkably,hence the equivalent load and distribution of external prestressing vary correspondingly.The calculation shows the relationship between the bar elongation and the adjust value of the key points deformation is not purely linear as well.This paper provided an effective arithmetic to establish the relationship,which could calculate an accurate numerical solution and supply correct adjusting magnitude for the smart controlling.