REPORT ON TESTS CONDUCTED WITH TWO 250 TON ANCHOR RODS ANCHORED IN SAND AND GRAVEL
1971
TWO RODS APPROXIMATELY 20M LONG WERE INSTALLED IN NATURAL SOIL AT A 30 DEGREE ANGLE OVER THE HORIZONTAL PLANE. THE DISTANCE BETWEEN THE HEADS OF THE RODS WAS 2,50M. THE RODS WERE POINTING IN DIFFERENT DIRECTIONS AT AN ANGLE OF APPROXIMATELY 20 DEGREES. SEALING WAS BY INJECTION OVER 8,50M IN SAND AND GRAVEL, THE REMAINING LENGTH BEING INSULATED AND SEALED BY A SYSTEM OF DUCTS SO AS NOT TO IMPOSE STRESSES ON THE UPPER LAYERS OF THE SOIL. THE CABLE CROSS-SECTIONS WERE OF THE ORDER OF 2000 SQUARE MILLIMETERS CONSISTING OF 48,7MM DIAMETER WIRES AND 12,15MM-DIAMETER WIRES RESPECTIVELY. BOTH RODS WERE PROGRESSIVELY TENSIONED: THE EXTENSION OF THE FIRST ROD REACHED 85MM UNDER 235T, THAT OF THE SECOND 100MM UNDER 230T. SUBSEQUENT CREEP OBSERVED DURING THE THREE DAYS OF TENSIONING DID NOT EXCEED 5MM. AFTER TENSIONING HAD BEEN CARRIED OUT AT 170T THE LOAD WAS REMOVED FROM ONE OF THE RODS. THE FORCE-EXTENSION CHARTS DURING LOAD REMOVAL AND LOAD REAPPLICATION COINCIDED PERFECTLY OVER THIS INTERVAL AND LED TO THE DETERMINATION OF ELASTICITY CORRESPONDING TO 8,50M OF CABLE. THIS TENDS TO DEMONSTRATE THAT THE UPPER PART OF THE SEALING ZONE ALONE (AND PERHAPS EVEN ONE PART OF THE WIRES INSIDE THE DUCT) IS SUBJECTED TO MOST OF THE SHEAR STRESSES IN CONTACT WITH THE SOIL.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
0
References
0
Citations
NaN
KQI