IMPACT AND STATIC LOADS ON ROAD SLABS

AN ELABORATE SERIES OF TESTS WAS CONDUCTED ON ROAD SLABS (7 FEET X 7 FEET), THE RESULTS OF WHICH GIVE A FAIR INDICATION OF THE RELATIVE ROAD RESISTANCE AND THE STRESSES DEVELOPED UNDER BOTH IMPACT AND STATIC LOADS. REINFORCING STEEL IN CONCRETE SLABS, IF PRESENT IN SUFFICIENT AMOUNTS AND SO PLACED AS TO RECEIVE TENSILE STRESS, ADDS TO THE RESISTANCE OF THE SLAB TO IMPACT. HOWEVER, FABRIC REINFORCING IS MORE EFFECTIVE UNDER IMPACT LOADS THAN UNDER STATIC LOADS. IN ALL CASES THE SLABS OFFERED A GREATER RESISTANCE TO IMPACT THAN TO STATIC LOADS, THE AVERAGE RATIO OF IMPACT TO STATIC BEING 1.99 FOR SLABS ON DRY SUBGRADE AND 1.3 ON WET SUBGRADE. CONCRETE SLABS WERE NOT STRENGTHENED BY THE ADDITION OF 2 INCH BITUMINOUS TOP FOR EITHER IMPACT OR STATIC LOADS. THE IMPACT RESISTANCE OF A PLAIN CONCRETE SLAB IS GREATER ON A DRY SUBGRADE, BUT THE MAXIMUM IMPACT FIBER STRESS AT BREAKING IS APPROXIMATELY THE SAME ON THE DRY AND WET SUBGRADES. IMPACT RESULTS SHOW THAT THE HEIGHT OF DROP OF THE SAME WHEEL IS LESS FOR THE DRY SUBGRADE AND GIVES HIGHER IMPACTS THAN ON THE WET SUBGRADE.

Media Info

  • Monograph Title: Proceedings of the Fourth Annual Meeting of the Highway Research Board Held at Washington, D.C., December 4-5, 1924
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00207131
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Nov 9 1970 12:00AM