CONCRETE CANTILEVERED BOXES ARE U.S. FIRST

POST-TENSIONED BOX GIRDER SEGMENTS MAKE UP ONLY THE MAIN SPANS OF THE BRIDGE ACROSS THE GULF INTER-COASTAL WATERWAY, A 200-FT SPAN FLANKED BY A 100-FT SPAN ON EACH SIDE. A LIFTING RIG AND MATING METHOD ARE BEING USED IN PLACE OF A LAUNCHING TRUSS. THE ERECTION OF THE 10-FT-LONG UNITS PROCEEDS IN BALANCED CANTILEVERS FROM SECTIONS BOLTED ATOP THE PIERS WITH 5-FT UNITS COMPLETING THE ENDS OF EACH GIRDER. THE 27-FT. WIDE WINGED SECTIONS WEIGH UP TO 52 TONS EACH. A 2-FT WIDE, CAST-IN-PLACE STRIP BETWEEN THE GIRDERS WILL COMPLETE THE DECK, TO BE TOPPED BY ASPHALTIC CONCRETE. THE PROCESS OF ERECTION OF THE 84 BOX SECTIONS IS DESCRIBED. TO ASSURE PERFECT MATING WHEN SEGMENTS WERE ERECTED ON A 5-DAY CURVE, THEY WERE CAST AGAINST EACH OTHER ON A 90-FT-LONG BED THAT WAS BUILT ON STEEL BEAMS WITH SCREW JACKS AT EACH END FOR ADJUSTMENTS. CONSTRUCTIONAL EXPERIENCES ARE DESCRIBED AND PROBLEMS ARE DISCUSSED. IT IS HOPED THAT THE PROJECT (WHICH WILL COST $2.82 MILLION) WILL LEAD TO STANDARDIZED ELEMENTS THAT WILL RELIEVE SOME OF THE PROBLEMS OF BUILDING BRIDGES AND VIADUCTS AND DOUBLE DECKING EXPRESSWAYS IN CONGESTED AREAS BY ELIMINATING FALSEWORK. IT IS EXPECTED THAT STANDARDIZATION WILL LEAD TO A DROP IN TIME AND COST.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/08919526
• Publication Date: 1973-4-5

Media Info

• Features: Photos;
• Pagination: p. 22-3
• Serial:
  • Engineering News-Record
  • Volume: 190
  • Issue Number: 14
  • Publisher: McGraw-Hill, Incorporated
  • ISSN: 0891-9526

Subject/Index Terms

• TRT Terms: Aerodynamic lift; Asphalt concrete; Box girders; Bridge engineering; Cantilevers; Construction; Erection (Building); Posttensioning; Standardization
• Uncontrolled Terms: Lifts
• Subject Areas: Bridges and other structures; Construction; Highways;

Filing Info

• Accession Number: 00215638
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 31 1973 12:00AM