Method and apparatus for repairing post-tensioned concrete

Abstract

An end cap secured to a tubular member for use in repairing post-tensioned concrete, including a first segment, a second segment, and a third segment. The first segment has a first end and a first opening, where the first segment is substantially cylindrical in shape. The second segment is substantially frustoconical in shape. The third segment has a second end and a second opening and is substantially cylindrical in shape. The second segment is disposed between and integral with the first segment and the third segment. A cavity is formed by the first, second, and third segments, where the first end is arranged to be secured to a tubular member and at least one cable is disposed longitudinally within the cavity.

1 . An end cap secured to a tubular member for use in repairing post-tensioned concrete, comprising:
 a first segment, having a first end and a first opening;   a second segment;   a third segment, having a second end and a second opening, the second segment is disposed between the first segment and the third segment;   a cavity formed therein by the first, second, and third segments, wherein the first end is arranged to be secured to a tubular member and at least one cable is disposed longitudinally within the cavity.   
     
     
         2 . The end cap of  claim 1 , wherein the first segment is substantially cylindrical in shape, the second segment is substantially frustoconical in shape, and the third segment is substantially cylindrical in shape. 
     
     
         3 . The end cap of  claim 2 , wherein the second segment is integral with the first segment and the third segment. 
     
     
         4 . The end cap of  claim 1 , wherein the first segment has a first diameter (D 1 ) and the third segment has a second diameter (D 2 ), and the first diameter is larger than the second diameter. 
     
     
         5 . The end cap of  claim 4 , wherein the first diameter (D 1 ) is approximately 2.375 inches and the second diameter (D 2 ) is approximately 0.67 inches. 
     
     
         6 . The end cap of  claim 4 , wherein the end cap has an outer surface and an inner surface and the tubular member has an outer surface, an inner surface, a first end, and a second end, and the first end of the first segment is secured to the first end of the tubular member such that the inner surface of the end cap contacts the outer surface of the tubular member. 
     
     
         7 . The end cap of  claim 6 , wherein the first end of the tubular member has a third diameter (D 3 ) and the third diameter (D 3 ) of the first end of the tubular member is slightly smaller than the first diameter (D 1 ) of the first segment. 
     
     
         8 . The end cap of  claim 1 , wherein a second end cap is secured to the second end of the tubular member. 
     
     
         9 . The end cap of  claim 1 , wherein the end cap is made of plastic. 
     
     
         10 . The end cap of  claim 9 , wherein the end cap is made of polypropylene. 
     
     
         11 . An end cap secured to a tubular member for use in repairing post-tensioned concrete, comprising:
 a first segment, having a first end and a first opening, wherein the first segment is substantially cylindrical in shape;   a second segment, wherein the second segment is substantially frustoconical in shape;   a third segment, having a second end and a second opening; wherein the third segment is substantially cylindrical in shape, the second segment is disposed between and integral with the first segment and the third segment;   a cavity formed therein by the first, second, and third segments, wherein the first end is arranged to be secured to a tubular member and at least one cable is disposed longitudinally within the cavity.   
     
     
         12 . The end cap of  claim 11 , wherein the first segment has a first diameter (D 1 ) and the third segment has a second diameter (D 2 ), and the first diameter is larger than the second diameter. 
     
     
         13 . The end cap of  claim 12 , wherein the end cap has an outer surface and an inner surface and the tubular member has an outer surface, an inner surface, a first end, and a second end, and the first end of the first segment is secured to the first end of the tubular member such that the inner surface of the end cap contacts the outer surface of the tubular member. 
     
     
         14 . The end cap of  claim 13 , wherein the first end of the tubular member has a third diameter (D 3 ) and the third diameter (D 3 ) of the first end of the tubular member is slightly smaller than the first diameter (D 1 ) of the first segment. 
     
     
         15 . The end cap of  claim 11 , wherein a second end cap is secured to the second end of the tubular member. 
     
     
         16 . A method of installing an end cap during the repair of a post-tension concrete structure, where the end cap includes a first segment, a second segment, and a third segment, the first segment having a first end, and the third segment having a second end, the method comprising the following steps:
 cutting an opening in a slab of concrete;   installing a temporary anchor device to transfer the load of at least one cable to the temporary anchor device;   cutting a section of the at least one cable;   removing a section of the at least one cable;   replacing the section of the at least one cable with a second section of at least one cable;   installing an encapsulated anchorage;   affixing a splice coupling to secure an end of the remaining at least one cable to an end of the second section of at least one cable and wherein the remaining at least one cable and the second section of the at least one cable are disposed within the splice coupling;   installing a tubular member, having a first end and a second end, to cover the splice coupling;   securing the first end of at least one end cap to the first end of the tubular member;   pouring concrete to fill the opening;   stressing the at least one cable after the concrete has cured and reached a specified compressive strength; and,   removing the temporary anchor device.   
     
     
         17 . A method of installing an end cap during the repair of a post-tension concrete structure, where the end cap includes a first segment, a second segment, and a third segment, the first segment having a first end, and the third segment having a second end, the method comprising the following steps:
 affixing a splice coupling to secure an end of at least one cable to an end of the second section of at least one cable and wherein the remaining at least one cable and the second section of the at least one cable are disposed within the splice coupling;   installing a tubular member, having a first end and a second end, to cover the splice coupling; and,   securing the first end of at least one end cap to the first end of the tubular member.   
     
     
         18 . The method of  claim 17 , the method further comprising the following steps:
 before affixing the splice coupling to secure the end of the remaining at least one cable, cutting an opening in a slab of concrete;   installing a temporary anchor device to transfer the load of at least one cable to the temporary anchor device;   cutting a section of the at least one cable;   removing a section of the at least one cable;   replacing the section of the at least one cable with a second section of at least one cable; and,   installing an encapsulated anchorage.   
     
     
         19 . The method of  claim 17 , the method further comprising the following steps:
 after securing the first end of at least one end cap to the first end of the tubular member, pouring concrete to fill the opening;   stressing the at least one cable after the concrete has cured and reached a specified compressive strength; and, removing the temporary anchor device.   
     
     
         20 . The method of  claim 17 , the method further comprising the following steps:
 after securing the first end of the at least one end cap to the first end of the tubular member, securing the first end of a second end cap to the second end of the tubular member.