Norwich bulletin., 1916-04-27

above the determined foundation win be removed The cells win then be filled with concrete. making a solid pier from tide level to the founda- ble of sustaining the great loads which 1t will be necessary to carry
 Above the tide level the piers and abutments will extend 25 feet high in an artistic design. They will furnish the support for the steel pedestals of the bridge trusses. which are to carry the railway tracks.
 The new bridge win be a fave-span structure. with bascule type of lift. This was chosen because of the say ing in time required for opening and closing to permit vessels to pass up or down stream. as compared with the time consumed in opening and closing draw span of the swing type. The i've spans from west to east will be 300 feet and sso feet About 1000 tons of steel win be used in the construc- ton of the bridge. The approaches to the bridge will be 1900 feet on the west side and 1.e00 feet on the east side. The abutments on either side will be of reinforced concreta- The extreme dimensions of the Foundations of the piers win be 42 feet by ss feet. and 1t will require about 4s.000 cubic feet of material
 In authorizing the construction of | tAAN AM9N 4AA4MAC8 ElNGE OTlQK6 Lne Ql- rectors of the New Haven acted fin line with the policy of the Elliott ad- ministration to put the property in a position to do the maximum amour, of business and to perform its duties as a common carried with the utmost safety and efficiency The operation oi | the present Thames river bridge as a single track has reduced the capacity | and efficiency of the entire main line from Boston to New York It has been | the intention of the directors to correct this sitxation as soon as there wa. any flnanciaf~ability to do so. The new bridge and approaches will cost approximately s2.60000o This sum fl much less than one-tenth of the entirt amount the company ehould spend, ai President Elliott has announced. tG bring the property up to the standard of New England. Tn the next ter years over $50, ,o00. 900 will have to b, expended upon improvements, it Is es
 ttmated. in order that trains may bl operated Co the fullest extent of econ
 omy, efficiency and safety. An illustra
 tion of the extent the company 1
 spending money to put the propert,
 upon basis suitable to the require
 ments of the sections it serves is af
 forded in a statement recently issued
 This showed that a total of over s1o, ordered since President Elliott ha
 
 In considering the engineering prob
 lems for this bridge. and designin
 the structure so that the most eco nomical and proper foundation pier could be worked out extensive bor
 ings were required. The borfnes yak
 en to determine the nature of tn
 materials, and at what depth found
 atfons should be carried, were mad : from lighters by the use of large fro
 casing pipe driven down to rock. Tn , material enclosed by the casing pin
 was pumped or lifted out and man samples carefully indexed and pre-
 served. Upon reaching the rock tn
 test holes were continued by borin l into the rock from ten to 20 fes by means of drills. so arranged ths a core was removed to permit its be 5 ing tested and examined to deterTnir ? its character. The examination | l this method required a total Of T,zs 3 lineal feet of borings. of which 6,6. feet were through overlying mud, cla
 and gravel. and 669 feet into roc v The number of individual borings wa 2 75, and the greatest depth reached 1 any boring was 1895 feet below To r water
 The general result of the borinJ indicated rock at great depth. Tn ? rock is overlaid by a bed of gray
 and sand varying from 50 to 100 fe U in depth, which is In turn overIa by a layer of mud and clay caryir d from so to 90 feet in depth. The "; K ter above the river bed varies fro e 50 to 10 feet fin depth. Toward Il east from the center of the river tl IT rock surface rises quite rapidl reaching an elevation at the caste n shore only 50 feet below low water