LARGE SCALE EARTH PRESSURE TESTS WITH MODEL FLEXIBLE BULKHEADS

A SERIES OF TESTS ARE REPORTED PERFORMED ON SCALE MODELS OF FLEXIBLE BULKHEADS SUBJECTED TO LATERAL EARTH PRESSURES, AND COMBINED ACTIVE AND PASSIVE EARTH PRESSURE TESTS. THE FIRST TEST DEMONSTRATED THE EFFECTIVENESS OF A SAND DIKE INTERPOSED BETWEEN THE BULKHEAD AND THE FLUID CLAY BACKFILL. THE LATERAL PRESSURES EXERTED AGAINST THE BULKHEAD WERE NO GREATER THAN IF THE ENTIRE BACKFILL WERE COMPOSED OF CLEAN SAND. THERE WAS NO EVIDENCE OF ARCHING WHEN THE BULKHEAD WAS BACKFILLED WITH SAND. THE LATERAL PRESSURES OF THE BACKFILLS WERE FOUND TO DECREASE DURING CONSOLIDATION WITHOUT ANY OUTWARD MOVEMENT BEING NECESSARY TO REDUCE THE LATERAL PRESSURES TO THEIR FINAL VALUE. INDUCED OUTWARD MOVEMENT OF THE BULKHEAD DID NOT DECREASE THE LATERAL PRESSURES OF THE CONSOLIDATED CLAY BACKFILL. ELECTRIC RESISTIVITY STRAIN GAUGES WERE EMPLOYED FOR THE MEASUREMENT OF BENDING STRAINS ON THE BULKHEAD AND WERE SUPPLEMENTED BY DEFLECTION MEASUREMENTS BY INDEPENDENT MECHANICAL MEANS. PORE PRESSURE MEASUREMENTS WERE MADE IN CLAY BACKFILLS WITH CARLSON CELLS. A PROCEDURE IS SUGGESTED FOR THE DESIGN OF FLEXIBLE ANCHORED BULKHEADS IN CONNECTION WITH CONSOLIDATED CLAY BACKFILLS OR REMOLDED PLASTIC NATURAL CLAYS. A GRAPHICAL PRESENTATION IS GIVEN OF THE RESULTS OF ACTUAL MEASUREMENTS DURING DIFFERENT TESTS IN THE FORM OF BENDING MOMENT, SHEAR, LATERAL PRESSURE AND DEFLECTION CURVES. LATERAL PRESSURE CURVES ARE EMPLOYED FOR THE PURPOSE OF DETERMINING BENDING MOMENTS. GOOD AGREEMENT WAS OBTAINED BETWEEN THE DEFLECTIONS MEASURED BY ENTIRELY INDEPENDENT MECHANICAL MEANS AND THE DEFLECTIONS COMPUTED FROM THE ELECTRICALLY MEASURED BENDING STRAINS BY THE MOMENT AREA AND THE ELASTIC WEIGHTS METHOD. THE DESIGN PROCEDURE PROPOSED FOR SAND BACKFILLS CONSISTS OF TAKING A DEPTH OF EMBEDMENT, ASSUMING A HINGE AT DREDGE LEVEL AND USING A PRESSURE DISTRIBUTION DIAGRAM THE SLOPE OF WHICH IS GIVEN BY AN EQUATION BASED ON AVAILABLE DATA CONCERNING ACTUAL MEASUREMENTS OF BENDING MOMENTS AND ANCHOR PULLS. A DESIGN PROCEDURE PARALLELING THE ONE SUGGESTED FOR SANDS IS PROPOSED FOR CONSOLIDATED CLAY BACKFILLS OR UNDISTURBED NATURAL CLAYS.

  • Supplemental Notes:
    • Final ReporT, 112 PP, 113 FIG, 35 TAB, 77 REF, 1 APP
  • Corporate Authors:

    Princeton University

    Department of Civil Engineering
    Princeton, NJ  United States  08450
  • Authors:
    • Tschebotarioff, G P
  • Publication Date: 1949-1

Subject/Index Terms

Filing Info

  • Accession Number: 00234429
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Dec 9 1994 12:00AM