Duct coupler for use with ducts in a wet joint of segmental concrete construction

Abstract

A duct coupling system has a first concrete segment, a first duct positioned in the first concrete segment so as to have an end extending outwardly therefrom, a second concrete segment, a second duct positioned in the second concrete segment so as to have an end extending outwardly therefrom in a direction toward the end of the first duct, and a tubular member slidably positioned over the ends of the first and second ducts so as to join the first and second ducts together in a liquid-tight relationship. The first concrete segment is positioned in spaced relation to the second concrete segment. A wet joint is formed in the space between the first concrete segment and the second concrete segment. The tubular member is embedded in the wet joint.

I claim: 
     
         1 . A duct coupling system comprising:
 a first concrete segment;   a first duct positioned in said first concrete segment so as to have an end extending outwardly therefrom;   a second concrete segment;   a second duct positioned in said second concrete segment so as to have an end extending outwardly therefrom in a direction toward the end of said first duct; and   a tubular member slidably positioned over said ends of said first and second ducts so as to join said first and second ducts together in a liquid-tight relationship.   
     
     
         2 . The duct coupling system of  claim 1 , said first concrete segment being positioned in spaced relation to said second concrete segment, the duct coupling system further comprising:
 a wet joint formed in the space between said first concrete segment and said second concrete segment, said tubular member being embedded in said wet joint.   
     
     
         3 . The duct coupling system of  claim 1 , said first duct having a plurality of ridges extending outwardly therefrom, said plurality of ridges having a first ridge in spaced relation to a second ridge, one of said first and second ridges being adjacent said end of said duct. 
     
     
         4 . The duct coupling system of  claim 3 , said second duct having a plurality of ridges extending outwardly therefrom, said plurality of ridges of said second duct having a first ridge in spaced relation to a second ridge, one of said first and second ridges of said second duct being adjacent to an end of said second duct. 
     
     
         5 . The duct coupling system of  claim 1 , said tubular member being movable between a first position overlying a portion of only one of said first and second ducts and a second position overlying both of the ends of said first and second ducts. 
     
     
         6 . The duct coupling system of  claim 4 , said tubular member having an inner wall overlying and adjacent to the ridges of said first and second ducts. 
     
     
         7 . The duct coupling system of  claim 1 , said tubular member having an inner diameter greater than an outer diameter of said first and second ducts. 
     
     
         8 . The duct coupling system of  claim 1 , further comprising:
 a first seal positioned over an exterior of said first duct adjacent the end thereof; and   a second seal positioned over an exterior of said second duct adjacent to the end thereof, said first and second seals being in liquid-tight sealing relation with said tubular member.   
     
     
         9 . The duct coupling system of  claim 4 , further comprising:
 a first seal positioned over an exterior of said first duct between said first and second ridges of said first duct; and   a second seal positioned over an exterior of said second duct between said first and second ridges of said second duct.   
     
     
         10 . The duct coupling system of  claim 9 , said first seal bearing against a surface of one of said first and second ridges of said first duct, said second seal bearing against a surface of one of said first and second ridges of said second duct. 
     
     
         11 . The duct coupling system of  claim 8 , each of said first and second seals being an elastomeric O-ring. 
     
     
         12 . A method of forming a wet joint between a first concrete segment and a second concrete segments, the method comprising:
 forming the first concrete segment with a first duct embedded therein such that said first duct has an end extending outwardly of one side of the first concrete segment;   forming the second concrete segment with a second duct embedded therein such that said second duct has an end extending outwardly of one side of said second concrete segment;   applying a tubular member over the end of said first duct;   sliding the tubular member toward the second duct such that the tubular member overlies the end of the first duct and overlies the end of the second duct; and   forming a wet joint between the first and second concrete segments such that said tubular member is embedded therein.   
     
     
         13 . The method of  claim 12 , further comprising:
 applying a first seal around an exterior surface of said first duct adjacent the end thereof; and   applying a second seal around an exterior surface of said second duct adjacent the end thereof.   
     
     
         14 . The method of  claim 13 , the step of sliding comprising:
 sliding the tubular member toward said second duct such that an inner wall of said tubular member bears against said first seal and said second seal in generally liquid-tight relationship.   
     
     
         15 . The method of  claim 13 , said first duct having a first ridge and a second ridge in spaced relation to each other adjacent the end of said first duct, said second duct having a first ridge and a second ridge in spaced relation to each other adjacent the end of said second duct, the step of applying the first seal comprising applying the first seal in a location between said first ridge and said second ridge of said first duct, the step of applying the second seal comprising applying the second seal in a location between said first ridge and said second ridge of said second duct. 
     
     
         16 . The method of  claim 15 , said first seal being applied so as to bear against one of said first and second ridges of said first duct, said second seal being applied so as to bear against one of said first and second ridges of said second duct. 
     
     
         17 . The method of  claim 13 , each of said first and second seals being an elastomeric O-ring. 
     
     
         18 . A duct coupling system comprising:
 a first concrete segment;   a first duct positioned in said first concrete segment so as to have an end extending outwardly therefrom;   a second concrete segment;   a second duct positioned in said second concrete segment so as to have an end extending outwardly therefrom and a direction toward the end of said first duct;   a tubular member slidably positioned over the ends of said first and second ducts so as to join said first and second ducts together in a liquid-tight relationship; and   a wet joint formed in a space between said first concrete segment and said second concrete segment, said tubular member being embedded in said wet joint.   
     
     
         19 . The duct coupling system of  claim 18 , further comprising:
 a first seal positioned over an exterior of said first duct adjacent the end thereof; and   a second seal positioned over an exterior of said second duct adjacent to the end thereof, said first and second seals being in liquid-tight sealing relationship with said tubular member.   
     
     
         20 . The duct coupling system of  claim 18 , said first duct and said second duct and said tubular member each being formed of a polymeric material.