DYNAMIC OVERTURNING LOADS ON DRILLED SHAFT FOOTINGS

DYNAMIC LOAD TESTS ARE SUMMARIZED ON A COHESIONLESS SAND, A SANDY CLAY AND A CLAYEY SAND. PRESENT ASSUMPTIONS IN FOUNDATION DESIGN ARE THAT STATIC LOADS ARE MORE CRITICAL THAN DYNAMIC LOADS OF THE SAME MAGNITUDE WHICH WAS CONFIRMED BY THESE TESTS. TEN MODEL TESTS OF DRILLED SHAFT FOOTINGS SUBJECTED TO DYNAMIC OVERTURNING LOADS WERE PERFORMED. COMPARED TO THE AVERAGE SIZE FOOTING USED FOR MINOR SERVICE STRUCTURES IN TEXAS, THE MODEL FOOTINGS WERE REDUCED BY A FACTOR OF SIX. THE RESULTS OF THE TESTS WERE COMPARED WITH THE RESULTS OBTAINED FROM THE THEORY DEVELOPED EARLIER IN THIS STUDY FOR STATIC PULLOVER LOADS. THE FOOTING RESISTANCE TO SINGLE DYNAMIC LOADS EXCEEDED THE STATIC PULLOVER RESISTANCE PREDICTED BY THE THEORY. FOOTING ROTATIONS DUE TO REPEATED DYNAMIC LOADS DID NOT EXCEED ONE DEGREE FOR 10,000 REPETITIONS OF THE DYNAMIC LOAD, WHICH WAS LESS THAN 50% OF THE STATIC PULLOVER LOAD. /BPR/

• Corporate Authors:

  Texas Transportation Institute

  Texas A&M University System, 1600 E Lamar Boulevard
  Arlington, TX  United States  76011

  Texas State Department of Highways & Public Transp

  11th and Brazos Streets
  Austin, TX  United States  78701

  Bureau of Public Roads /US

  400 7th Street, SW
  Washington, DC  United States  20590
• Authors:
  • SMITH, H L
  • Dunlap, W A
  • Ivey, D L
• Publication Date: 0

Subject/Index Terms

• TRT Terms: Design; Drilling; Dynamic loads; Footings; Foundation soils; Granular soils; Load tests; Overturning; Sand; Sandy clays; Shafts (Machinery); Theory
• Uncontrolled Terms: Model tests
• Subject Areas: Bridges and other structures; Design; Geotechnology; Highways;

Filing Info

• Accession Number: 00207947
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Report/Paper Numbers: No 105-4
• Files: TRIS, STATEDOT
• Created Date: Jul 14 1970 12:00AM