Show v MODERN BRIDGE Why Bridges Are Built Less Permanent Today Anchorage Most Missouri Engineer Says He Has Seen Several Otherwise Which Have Been Swept Away Because of Their Insecure Anchor-age Tubular Piers as The question is frequently are the bridges which we build today less permanent than those which the ancients says F. J. deputy state highway engineer of in Good New One answer is the item of chiefly because we build a vastly greater number of bridges than did the We build solely for the accommodation of the as we live by peaceful whereas the ancients lived by being almost continually at and built mainly for army k financial conditions and the rapid growth of progress have made it necessary to do some things in the line of building which were regrettable because the prime object was to build cheap sometimes quickly built That state of affairs is and I am sure we all agree that the class of bridges we are to build in this state in the future should keep pace with the improved V There are conditions when it is the best policy to build a masonry perhaps a steel arch or a steel through There is no doubt but that when the funds are on hand and the conditions at the site are favorable it is best to build a concrete It will also be found to be economical in the long run to build concrete floors on all steel bridges regardless of the length of Many county officials through an idea that they are saving the county money build spans much too short for the waterway This is a serious mistake and the cause of the destruction of nearly all of those smaller bridges which have been by high County engineers should see that bridges are placed at a sufficient height above high water so that they will not catch Particular attention should also be given to the placing of anchor I have seen several expensive bridges washed off abutments during a time of high water when anchor bolts which had been omitted would have saved The state highway engineer is f asked about tubular and the inquirer is generally prejudiced against The proper material out of which to build piers or abutments is stone and Tubular piers an excellent They have been used for years not only on highway but also by There are several reasons for In the first there is usually a vast difference in the and were it not for the tubular pier many bridges in Missouri could not have been built Concrete or masonry piers require more excavation S l and when water level is reached an expensive dam is required along with much more pumping th necessary in sinking a tubular which itself aC acts as a When there is no rock the difference in cost is even There have been more failures of concrete and piers than there have been of tubular piers cases this is due to the poor construction of the Therefore there are many masonry piers built of the game class of stuff and in the same manner the mason employs when building a cellar wall in his The pressure against a tubular pier at time of high water is not great owing to its cylindrical it is also Dot apt to hold drift for this It is bad practice to set a tubular pier on a rock foundation in a stream where it has only a foot or two of gravel or clay to In this case it is best policy to build a concrete or masonry pier even though the first cost be twice that of tubular Town and |