BRIDGE DEBUT FOR LIGHTWEIGHT AGGREGATE

THE FIRST LIGHTWEIGHT AGGREGATE CONCRETE BRIDGE TO BE BUILT OVER A PUBLIC HIGHWAY IN THE UK IS DESCRIBED. GLASSHOUSE WOOD BRIDGE CARRIES A 1.8M WIDE FOOTPATH OVER THE KENNILWORTH BY-PASS. TRRL WILL INCLUDE THIS BRIDGE IN ITS LIGHTWEIGHT BRIDGE STRUCTURES TESTING PROGRAMME. THE BRIDGE IS A TWO-PINNED REINFORCED CONCRETE PORTAL FRAME STRUCTURE WITH DENSE CONCRETE HINGES. ALL CONCRETE ABOVE THE HINGE ZONES USES LIGHTWEIGHT AGGREGATE. THE PORTAL WAS DESIGNED USING THE IBM COMPUTER PROGRAM "STRESS" AND IS CONSISTENT WITH THE REQUIREMENTS OF CP 114. CREEP AND SHRINKAGE EFFECTS IN LIGHTWEIGHT AGGREGATES ARE MORE SEVERE THAN IN DENSE CONCRETE. A LONG-TERM DEFLECTION EQUAL TO THE INITIAL DEFLECTION DUE TO PERMANENT LOADS WAS TAKEN AS AN ESTIMATE TO INCLUDE CREEP AND SHRINKAGE EFFECTS. THE LIGHTWEIGHT AGGREGATE CONCRETE WAS DESIGNED TO HAVE A MINIMUM 28-DAY STRENGTH OF 30MN/SQ.M, A MAXIMUM FRESH WET DENSITY OF 1850 KG/CU.M AND AN ANTICIPATED EVENTUAL AIR-DRY DENSITY OF 1700 KG/CU.M. THE MIX PROPORTIONS ARE GIVEN AND SAMPLES OF THE MIX GAVE A 28-DAY CUBE STRENGTH OF 45.75MN/SQ.M. THE IN-SITU CASTING OF THE BRIDGE IS DESCRIBED.

  • Availability:
  • Corporate Authors:

    IPC Building and Contract Journals Limited

    32 Southwark Bridge Road
    London SE1 9EX,   England 
  • Publication Date: 1974-6-27

Media Info

  • Features: Photos;
  • Pagination: p. 25
  • Serial:
    • CONTRACT JOURNAL
    • Volume: 259
    • Issue Number: 4947
    • Publisher: Reed Business Information, Limited
    • ISSN: 0010-7859

Subject/Index Terms

Filing Info

  • Accession Number: 00081101
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Apr 8 1975 12:00AM