CONCRETE STRENGTH OF THE SLIPFORM CONCRETED PIER OF THE ANGERED BRIDGE IN GOTHENBURG

BETONGHAALLFASTHET I ANGEREDSBRONS GLIDFORMSGJUTNA PELARE

An investigation was carried out concerning the strength of four of the slipform concreted piers of the angered bridge in Gothenburg. At each 24 test places standard and site cube specimens were cast in the same concrete as the test place at which cylinder specimens were drilled out. Both the cylinders and the cube specimens were then tested so that a comparison could be made between the strength of the finished piers and the strength of the corresponding cube specimens. At each test place the concrete strength of the pier was estimated by using a rebounding hammer. As the weather conditions varied the temperature and the moisture content of the ambient air were continuously registered. Furthermore the concrete temperatures of the piers and some of the site cube specimens were measured. The observed level of strength in the piers seems to be in agreement with the strength obtained at building site conditions of other conventionally cast concrete structures. However the strength of the concrete at the surface and about 20 mm inwards was found to be decreased, probably due to poor curing conditions, as inside the pier walls. Predicting the strength of the piers by means of testing standard cube or site cube specimens as well as rebounding hammer tests showed about the same precision. As far as the accuracies of these methods are concerned a calibration by testing a few drilled out cylinders may be convenient, especially when the strength prediction is based on rebounding hammer tests. In the future, Swedish concrete regulations bbk 78, quality requirements for finished structures are proposed. The observed compressive strength of the studied piers of the angered bridge does not quite fulfil these requirements. Therefore it can be argued that they are too severe due to the fact that they are mainly based on investigations carried through within the laboratories and not at normal building site conditions as the present investigation, or that the average strength of the standard cube specimens at the angered bridge was too low. More research outside the laboratories seems valuable however before the quality requirements for finished structures can finally be established in regulations. (TRRL)

  • Corporate Authors:

    Swedish National Road Administration

    Fack S-10220
    Stockholm 12,   Sweden 
  • Publication Date: 1979-8

Language

  • Swedish

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 62 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00316515
  • Record Type: Publication
  • Source Agency: Swedish National Road and Transport Research Institute (VTI)
  • Report/Paper Numbers: TB 133 Monograph
  • Files: ITRD, TRIS
  • Created Date: Oct 27 1980 12:00AM