RCC bridges are more safe and useful in comparison to the steel truss and bailey

MAJOR BRIDGES ON HIGHWAY SHOULD BE RCC INSTEAD OF STEEL TRUSS AND BAILEY:--The highway authority  should  prefer RCC bridges  on the  main  roads where the  traffic  of the road is more  than  the routine  and  is continued for twenty  four hours  As the steel truss and bailey bridges are designed for the  restricted  loadings and in the case of  heavy duty  loading factor of  safely could be  affected and the stresses so developed  on the  preface line of the  movements may get strained and in balance  and may develop the   cracks in main stream of the trusses and could  also be  collapse  even if the factor of the  safety cross over the  climax of its value designed for the  safe loadings  only which  should  not be  enhanced  till the  recovery  of original  position  of  the  structure  how ever in the case of the RCC bridges factor of the  safety could be  well maintained and designed for the safe loadings  but  in the  hilly areas it is  very difficult to get the  safe bearing  capacity of the  soil at founding  levels as required  in the  sub structure and  generally  in the  maximum  cases the  substructure fails during the  rains or the earthquakes and the  super structure  damaged due to this uncertainty  So it is  necessary to verify the  safe bearing  capacity of the  soil after  its testing at the  proposed site of the  bridge and finalize the  design data after obtaining the  necessary  approval of the  competent  higher  authority however the  RCC bridges  are more  safe and  useful in comparison to the other  alternatives  arranged temporary  for the  crossing of the rivers.