TIED-BACK EXCAVATION WALL FOR SEATTLE FIRST NATIONAL BANK

EXPERIENCE WITH TIED-BACKS AS REPLACEMENTS FOR RACKERS IN DEEP EXCAVATIONS IS DESCRIBED IN SEATTLE AND IN SAN FRANCISCO. THE EXCAVATION FOR THE FIRST NATIONAL BANK BUILDING OF SEATTLE IS IN A STEEP HILLSIDE SITE. THE VERTICAL CUTS ON THE FOUR SIDES OF THE BLOCK-SQUARE EXCAVATION WERE SHORED BY A SYSTEM PROVIDED AN UNOBSTRUCTED CONSTRUCTION AREA WITHIN WHICH THE CAISSON AND SPREAD FOOTING FOUNDATIONS COULD BE PLACED AND THE STRUCTURE ERECTED. SOLDIER PILES ARE THREE FEET ON CENTER; 20-IN. EARTH GAP BETWEEN IS COATED WITH AEROSPRAY 52 BINDER, WHICH PREVENTS THE SOIL FROM DRYING OUT, THUS REQUIRING NO WOOD LAGGING. AS EXCAVATION APPROACHED COMPLETION, GRADUALLY INCREASING INWARD MOVEMENT OF THE LONGEST SOLDIER PILE OCCURRED. ACCELERATED CONSTRUCTION OF THE BOTTOM LEVEL OF BASEMENT WALL STOPPED MOVEMENT. A TOTAL OF 726 TIE-BACKS WERE PLACED IN 12-IN. OR 16-IN. DIAMETER HOLES, AUGERED FROM THE EXCAVATION. TO DETERMINE ANCHO PERFORMANCE, 7 PULLOUT TESTS WERE PERFORMED OF WHICH FIVE WERE ON ANCHORS IMBEDDED IN CLAY AND 2 ON ANCHORS IN SAND. TO MEASURE THE PERFORMANCE OF THE HIGH SECTIONS OF THE TIED-BACK SHORING, RECTILINEAR EXTENSOMETERS WERE INSTALLED IN HORIZONTALLY DRILLED HOLES AS THE EXCAVATION PROGRESSED.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/10480594
• Supplemental Notes:
  • Vol 40, No 3, PP 62-64, 2 FIG, 2 PHOT
• Authors:
  • Shannon, W L
  • Strazer, R J
• Publication Date: 1970-3

Media Info

• Serial:
  • Civil Engineering
  • Publisher: American Society of Civil Engineers
  • ISSN: 0885-7024
  • Serial URL: http://www.pubs.asce.org/ceonline/newce/html

Subject/Index Terms

• TRT Terms: Augers; Excavations; Extensometers; Pull out test; Shoring; Spread footings; Support piles; Testing; Tiebacks
• Uncontrolled Terms: Anchors
• Old TRIS Terms: Auger borings; Pullout
• Subject Areas: Construction; Highways;

Filing Info

• Accession Number: 00215274
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 3 1970 12:00AM