Masonry wall tension device and method for installing same

Abstract

Masonry walls of buildings supported on concrete foundations are strengthened against destructive wind and seismic forces by spaced elongated members inserted inside the hollow masonry walls. The spaced elongated members are secured to the continuous masonry bond beam and the foundation. Tension means at the top of the masonry wall make the elongated members taut creating a continuous tension load path from bond beam to the foundation.

1 . A tension device for use in a masonry building which has a concrete foundation including at least one masonry wall supported on and attached in a bore in the employing foundation and a continuous masonry bond beam formed at the upper portion, each masonry wall formed of a plurality of side by side vertical hollow wall sections, said tension device comprising an elongated member positioned inside a hollow of each wall section, said elongated member having upper and lower portions extending into and secured to such foundation and extending through such masonry bond beam, and means for selectively tensioning said elongated member for causing such at least one wall section to be in compression.  
   
   
       2 . The tension device as defined in  claim 1  wherein said upper portion of said elongated member includes a threaded upper stud.  
   
   
       3 . The tension device as defined in  claim 2  wherein said threaded upper stud passes through a passageway in a masonry bond beam and extends above it, and said means for tensioning said elongated member includes a nut, said nut being threaded on said upper stud and tightened to tension said elongated member between such bond beam and such foundation.  
   
   
       4 . The tension device as defined in  claim 1  further including threads formed on said lower portion of elongate member and adhesive disposed within such bore for securing said lower portion firmly inside such bore.  
   
   
       5 . The tension device as defined in  claim 1  wherein said elongated member is substantially rigid.  
   
   
       6 . The tension device as defined in  claim 1  wherein said elongated member includes a length of wire rope having opposite ends.  
   
   
       7 . The tension device as defined in  claim 6  further including a bulbous element attached at one said end of said wire rope and integral one said end of said wire rope.  
   
   
       8 . The tension device as defined in  claim 7  further including another bulbous element attached to another said end of said wire rope, said another bulbous element being adapted to be secured to such foundation.  
   
   
       9 . The tension device as defined in  claim 7  wherein said threaded upper end stud passes through said bulbous element and extends through a passageway in the masonry bond beam thereabove, said means for tensioning including a threaded nut threadedly engaged with said upper threaded end stud for tensioning said wire rope, and a washer surrounding said upper threaded end stud and sandwiched between said nut and the masonry bond beam.  
   
   
       10 . The tension device as defined in  claim 1  wherein said elongated member is a threaded rod.  
   
   
       11 . The tension device as defined in  claim 1  wherein said elongated member is a rebar, said rebar including threaded upper and lower end studs, said threaded upper and lower end studs being welded to said rebar.  
   
   
       12 . The tension device as defined in  claim 1  wherein said elongated member is a rebar, said rebar including threaded upper and lower end studs, said threaded upper and lower end studs being welded to said rebar.  
   
   
       13 . The tension device as defined in  claim 1  wherein said elongated member is substantially non-stretchable.  
   
   
       14 . In a masonry building including a concrete foundation, a plurality of masonry walls supported on and attached to the foundation, and a continuous masonry bond beam formed at the upper portion of the plurality of masonry walls, the plurality of masonry walls comprising a plurality of side by side vertical hollow wall sections, at least one elongated member being positioned inside each of the masonry walls, each said elongated member extending into and secured to the foundation and extending through the masonry bond beam, and means for tensioning each said elongated member a predetermined amount causing each of the masonry walls to be in compression.  
   
   
       15 . In the building of  claim 14  wherein each said elongated member includes threaded upper studs.  
   
   
       16 . In the building of  claim 15  wherein said upper threaded stud of each said elongated member passes through a passageway in the masonry bond beam and extends above it, said means for tensioning each said elongated member including a nut, each said nut being threaded on said upper stud and tightened to tension each said elongated member.  
   
   
       17 . In the building of  claim 15  wherein said lower stud of each said elongated member is adapted to be secured to the foundation.  
   
   
       18 . A method for tensioning a masonry wall having a plurality of sections each formed of vertically aligned hollow masonry blocks creating a continuous vertically disposed passageway supported on a concrete foundation, comprising the steps of: 
 A. drilling a plurality of spaced bores into the concrete foundation below each passageway;    B. inserting a plurality of elongated tension members, each having upper and lower end portions and having a predetermined length greater than the height of the masonry wall to be tensioned by the elongated member inside each passageway;    C. securing the lower ends of each elongated member into a respective bore in the foundation;    D. securing the upper end of each elongated ember to an upper portion of respective section; and    E. tensioning the upper end portion of the plurality of elongated member to an upper portion of respective section;    
   
   
       19 . The method of  claim 18  wherein step D includes the steps of: 
 F. positioning the masonry bond beam on top of the masonry wall;    G. forming a vertically disposed passageway through a bond beam;    H. positioning the upper end of a tension member through the passageway formed in step G;    I. installing a sleeve around the upper portion of the tension member and downwardly through the passageway of step G; and    J. pouring concrete into the masonry bond beam and around the sleeve installed in step  1 .    
   
   
       20 . The method of  claim 18  wherein step E includes the steps of: 
 F. placing a washer and a nut over the upper end portion of the elongated member that extends through the passageway passing through the masonry bond beam; and    G. tightening the nut to tension the elongated member and place the masonry wall under compression.    
   
   
       21 . A method for tensioning a masonry wall in a masonry building including a concrete foundation, the masonry wall supported on and attached to the foundation, and a continuous masonry bond beam formed at the upper portion of the masonry wall, the masonry wall including a plurality of vertical hollow wall sections, the hollow wall sections including a plurality of hollow masonry units, comprising the steps of: 
 A. accessing the interior of the hollow masonry units located adjacent the bottom of the masonry wall to expose a surface portion of the foundation below the masonry wall;    B. drilling an elongated bore into the exposed surface portion of the foundation;    C. providing a vertical passageway through the bond beam;    D. vertically inserting a lower end of elongated member having a predetermined length greater than a height of the masonry wall inside the hollow masonry units;    E. securing the lower end of the elongated member to the foundation; and    F. tensioning the elongated member to compress the masonry wall.    
   
   
       22 . The method of  claim 20  wherein step F includes the steps of: 
 G. placing a washer and nut over the threaded upper end of the elongated member that extends through the passageway through the masonry bond beam; and    H. tightening the nut to tension the elongated member and place the masonry wall under compression.    
   
   
       23 . A tension device for use in a two-story building which has a roof and a concrete foundation including at least one first-story masonry wall supported on and attached in a bore in the foundation employing a continuous masonry bond beam having a vertical passageway therethrough formed at the upper portion of each masonry wall formed of a plurality of side by side vertical hollow wall sections, said tension device comprising an elongated member located inside a hollow of each wall section, said elongated member having a lower portion having top and bottom end portions extending into and secured to such foundation and extending vertically upwardly through the passageway in the masonry bond beam and an upper portion having top and bottom end portions attached to said top end portion of said lower portion of said elongated member and extending vertically to the roof and attached thereto, and means for tensioning said elongated member for causing such masonry wall section to be in compression.  
   
   
       24 . The tension device as defined in  claim 23  wherein said means for tensioning said elongated member includes a first adjustment means attached to said top portion of said lower portion of said elongated member for tensioning said lower portion of said elongated member and a second adjustment means attached between said top portion of said upper portion of said elongated member and the roof of such building for tensioning said upper portion of said elongated member.