Mining work beneath a 36 M long twin-span simply supported bridge carrying the A632 over the M1 in Derbyshire has caused greater movements of the abutments than was predicted. The rapid movement of up to 4 mm per day threatens to close the 75 mm expansion joint at each end of the deck slab. The immediate solution was to enlarge the expansion joint by cutting away the 230 mm wide nib at the top of the floating slab tied to the abutment. The upper section could be sawed but the lower two thirds had to be stitch-drilled. To prevent the complete closure of the joint rows of fregssinet flat jacks were inserted to hold back the slab. Because the rocker columns were designed for only a 75 mm movement, military trestling has been inserted adjacent to each abutment to support the outer ends of the deck slabs. It is hoped that the rate of movement is slowing down and that the method of permanent remedial work can soon be decided. However it is estimated that the cost of permanent and temporary repairs will be found170000. /TRRL/

Media Info

  • Features: Figures; Photos;
  • Pagination: p. 16-17
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00195502
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Sep 15 1979 12:00AM