REGROUTABLE PRESTRESSED TIE BACKS

A NEW FOUR-LANE TUNNEL UNDER THE MOBILE RIVER IS BEING CONSTRUCTED ON INTERSTATE ROUTE 10 IN MOBILE, ALABAMA. THE CONSTRUCTION LIMITS OF THE PROJECT AT ONE POINT ARE RESTRICTED BY THE CLOSE PROXIMITY OF MANY BUILDINGS OF HISTORICAL IMPORTANCE. SOIL BORINGS OF THE AREA INDICATED A 20-FOOT LAYER OF CLAY OVER 65 FEET OF SAND UNDERLAIN BY A VERY STIFF GRAY CLAY, AND THERE EXISTS A HIGH WATER TABLE WHICH MUST BE MAINTAINED WITHIN PLUS OR MINUS 2 FEET OF NORMAL, OUTSIDE THE EXCAVATION, AS A PREVENTIVE MEASURE AGAINST SETTLEMENT OF BUILDINGS ADJACENT TO THE PROJECT. THE CONTRACTOR DECIDED THAT SINGLE-WALL COFFERDAMS WITH SOME TYPE OF TIEBACK WAS THE ANSWER. INSTALLATION BIDS WERE RECEIVED FROM SEVERAL FIRMS, WITH SOLETANCHE OF PARIS, FRANCE, SUBMITTING THE LOW BID FOR AN INSTALLATION REQUIRING ONLY HALF THE NUMBER OF TIEBACKS PREVIOUSLY CONSIDERED REQUIRED BY THE CONTRACTOR. SOLETANCHE'S LOW BID WAS BASED ON THE USE OF THEIR PATENTED INJECTION RENOUVELABLE SOUS PRESSION (I. R. P.) TIE BACK SYSTEMS OF PRESTRESSED ANCHORS WHICH PERMITS TESTING OF EACH TIEBACK AND THEN SETTING TO THE COMPUTED LOAD WITH THE ADDED ADVANTAGE OF HAVING THE CAPABILITY TO REGROUT AND RESTRESS SHOULD A TIEBACK FAIL. THE SYSTEM STRUCTURE AND THE PROCEDURE FOR TIEBACK PLACEMENT ARE DESCRIBED. /AUTHOR/

  • Authors:
    • Umbs, R M
  • Publication Date: 1971-8

Media Info

  • Features: Figures;
  • Pagination: p. 5-13
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00236347
  • Record Type: Publication
  • Files: TRIS
  • Created Date: May 29 1972 12:00AM