VIBRATORY SOIL STABILIZATION

TODAY'S DEMAND FOR BUILDING LAND IS ENCOURAGING THE DEVELOPMENT OF ECONOMICAL ENGINEERING TECHNIQUES TO STABILIZE THE SOILS OF FILLED SITES AND OTHER BAD GROUND CONDITIONS. ONE SOLUTION, PARTICULARLY SUITABLE FOR INDUSTRIAL STRUCTURES AND HOUSING, IS VIBRATORY SOIL STABILIZATION. THE PROCESS WAS ORIGINATED BY JOHANN KELLR GMBH MORE THAN 30 YEARS AGO. SOIL STABILIZATION ALLOWS HIGH BEARING PRESSURES TO BE CARRIED AT SHALLOW DEPTHS WHILST RETAINING SIMPLE SHALLOW FOUNDATIONS. THE TECHNIQUE USES A LARGE POKER VIBRATOR, CONSISTING BASICALLY OF A HEAVY METAL TUBE ENCLOSING AN ELECTRIC MOTOR AND ECCENTRIC WEIGHT SYSTEM, SUSPENDED FROM A CRANE. IT IS UNUSUAL TO CARRY OUT STABILIZATION BEYOND A DEPTH OF 12 M BELOW GROUND LEVEL. ON MOST SITES STABILIZATION CAN BE CARRIED OUT BY A PROCESS SUCH AS VIBRO REPLACEMENT, IN WHICH THE VIBRATOR PENETRATES THE WEAK SOIL UNDER ITS OWN WEIGHT ASSISTED BY THE VIBRATIONS. UPON REACHING THE DESIRED DEPTH--NORMALLY FIRM STRATA--IT IS REMOVED AND A SMALL QUANTITY OF GRADED STONE AGGREGATE FED INTO THE HOLE. THE VIBRATOR IS REPLACED AND USED TO COMPACT THE INFILL AND FORCE THE STONE AGGREGATE AGAINST THE SURROUNDING SOIL. REPETITION OF THIS CYCLE PRODUCES A CONTINUOUS COLUMN OF COMPACT STONE TIGHTLY INTERLOCKED WITH THE SURROUNDING GROUND. VERY LOOSE OR SOFT WATERLOGGED SOILS OR SILTS ARE NOT SUITABLE FOR STABILIZATION BY THE VIBRO REPLACEMENT SYSTEM. STABILIZATION OF THESE SOILS CAN BE EFFECTED BY THE VIBRO FLOTATION SYSTEM IN WHICH HIGH PRESSURE WATER JETTING FROM THE TIP OF THE VIBRATOR IS USED TO FLUSH OUT UNSTABLE SOILS AND SUPPORT THE HOLE FORMED BY THE VIBRATOR. GRANULAR SOILS PERMIT EFFICIENT VIBRATORY STABILIZATION AND ALLOWABLE BEARING PRESSURES IN SAND IN THE ORDER OF 43 TON/SQ M. SOFT COHESIVE SOILS ARE COMMONLY ENCOUNTERED AROUND THE MAJOR ESTUARIES--AS ARE AREAS OF LAND RECLAIMED WITH DREDGED MATERIALS. IN THESE CONDITIONS SOIL STABILIZATION TECHNIQUES CAN BE USED TO STRENGTHEN THE WEAK SOILS BENEATH STORAGE AREAS, ALLOWING HIGH LOADING INTENSITIES TO BE CARRIED WITHOUT THE POSSIBILITY OF SHEAR FAILURE. /CEPWR/

  • Corporate Authors:

    Gkh Foundations Ltd

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  • Publication Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 00236258
  • Record Type: Publication
  • Source Agency: Civil Eng & Public Works Review /UK
  • Files: TRIS
  • Created Date: Jan 31 1972 12:00AM