INDUSTRIALIZED BRIDGE BUILDING

SEVERAL TYPES OF PREFABRICATED BRIDGE SYSTEMS ARE DESCRIBED. THE UNIT MODULE CONSTRUCTION CONSISTS OF CLIPPING ON PRECAST DECK PANELS COMPLETE WITH FULL ROADWAY WIDTH AND CURBS. ANOTHER TYPE OF BRIDGE USING PRECAST, PRESTRESSED COMPONENTS, INCLUDING PINS, IS CALLED LINEAR COMPONENT CONSTRUCTION. THE DECK MEMBERS ARE EITHER T OR INVERTED U SHAPE, SPANNING BETWEEN SUPPORTS, FOR SHORT SPAN BRIDGES UP TO 50 FEET, EXTRUDED PRESTRESSED CONCRETE SECTIONS CAN BE INCORPORATED INTO THE STRUCTURE. FOR MEDIUM AND LONG SPAN BRIDGES, PREFABRICATED CONCRETE MODULES USUALLY AS FULL WIDTH HOLLOW BOX SECTIONS ARE USED AS SPANNING ELEMENTS. A MOBILE, DEMONSTRABLE, REUSABLE ERECTION TRUSS OF STEEL IS USED FOR PLACING PRECAST CONCRETE UNITS. THE SLIP LAUNCHING TECHNIQUE MEANS THAT THE BRIDGE CAN BE ASSEMBLED ADJACENT TO THE SPAN ON ROLLERS AND THEN SLID ONTO ITS PINS. ALTHOUGH THIS SYSTEM HAS BEEN USED ONLY FOR STEEL STRUCTURES, IT CAN BE ADAPTED FOR PRESTRESSED CONCRETE SPANS AS WELL. /AUTHOR/