BAR SPACER SETS PACE FOR SLIPFORM PAVER

A MINNESOTA CONTRACTOR PLACES 1,600 SQUARE YARDS OF CONCRETE PAVEMENT EACH HOUR, 10 HOURS PER DAY, EQUIVALENT TO 60 FEET OF 2-LANE INTERSTATE PAVEMENT PER HOUR WHILE PLACING AND TYING CONTINUOUS-REINFORCEMENT BARS AHEAD OF THE PAVING MACHINE. THIS IS ACHIEVED WITH A BAR SPACER BUILT ON THE CHASSIS OF AN OLD BULL FLOAT THAT WAS ONCE PART OF A PAVING TRAIN. AN ON-BOARD ENGINE DRIVES TWO OF THE FOUR PLUMP AIRCRAFT TIRES THAT CARRY THE FRAME A COUPLE OF FEET ABOVE THE PREPARED BASE. WHEELS STRADDLE THE SECTION TO BE PAVED. MIDWAY BETWEEN THE FRONT AND REAR WHEELS OF THE CHASSIS IS A LONG TRANSVERSE AXLE WITH 52 PULLEY WHEELS TO KEEP LONGITUDINAL BARS AT THE PROPER SPACINGS AND A DEVICE THAT DISPENSES TRANSVERSE BARS AT EXACT INTERVALS OF 4 FEET AS THE MACHINE ADVANCES. ANOTHER SET OF 52 PULLEY SHEELS ON AN AXLE NEAR THE FRONT OF THE RIG ACTS AS A LIFTING DEVICE AND MAKES CERTAIN THAT THE LONGITUDINAL BARS STAY IN PARALLEL ALIGNMENT. THE MECHANISM THAT SPACES THE TRANSVERSE BARS IS LOCATED BEHIND THE LAST SET OF SPACER PULLEYS AND BELOW THE BARS FEEDING OFF THE PULLEYS. THE SPACER CONSISTS OF PAIRS OF UPRIGHT TOGGLE ARMS THAT REACH UP THROUGH THE PLANE OF THE LONGITUDINAL BARS. CONCRETE COVER BETWEEN THE ENDS OF THE TRANSVERSE BARS AND THE EDGES OF THE PAVEMENT IS LESS THAN 2 INCHES, SO BAR PLACEMENT MUST BE ACCURATE. THE FIRST STEP IN STEEL PLACEMENT IS TAKEN BY CREWMEN WHO DISTRIBUTE THE BARS IN EACH BUNDLE ACROSS THE ROADBED AND THEN TIE THEM WITH PROPER ENDLAP TO THE BARS OF THE PREVIOUSLY PLACED BUNDLE. LEADING THE PAVING TRAIN IS A NEW CMI BELT PLACER. THIS IS FOLLOWED BY THE LATEST IN REX SLIPFORM PAVERS. BOTH RIGS ARE GUIDED AUTOMATICALLY ALONG A TIGHTWIRE AT THE EDGE OF THE ROAD. THE AUTOMATIC BATCH PLANT IS BUILT WITH TWO 9-YARD MIXERS IN TANDEM. THE BASE AHEAD OF THE PAVING TRAIN IS COMPACTED BY THE VIBRATORY ROLLER.

  • Supplemental Notes:
    • Vol 50, No 12, PP 76-81, 12 PHOT
  • Authors:
    • Juergens, R E
  • Publication Date: 1968-12

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Filing Info

  • Accession Number: 00215152
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 12 1970 12:00AM