Theoretical and practical research carried out by Harold Sidwell of Queens University Belfast into the use of combined precompression and pre-tension in steel, timber and concrete structures is discussed. Reference is made to experiments whereby the load-carrying capacity of steel bars was improved by 125 per cent using both pre-tension and precompression compared with a 20 per cent increase using precompression alone. Sidwell has also shown that 'stretched' concrete columns can lead to economies in design, particularly for tall bridge piers. The first method used high tensile steel tubes, compressed by internal tensile tendons which were released when bonded into the concrete. More recently, wires cast into concrete with their ends proud have been used so that loads could be applied to compress the unbonded wires into the concrete. /TRRL/


  • English

Media Info

  • Features: Figures; Photos;
  • Pagination: 29 p.
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00189631
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: May 11 1979 12:00AM