Self-locking joint for reinforced concrete pile sections

Abstract

Two pile sections are joined together by interfitting means in their opposed ends. One pile has a plurality of lock bars (7a) extending substantially perpendicular to the end plate (3a), comprised of notches (14a, 14b) formed periphery at the lower portion (14). The other pile has a plurality of lock sockets (7b) mounted substantially perpendicular to the end plate (3b), comprised flaps (13a, 13b) within the cavity, formed from its opposed side walls and bending towards the axis of the lock socket cavity. When in splicing operation of the pile sections (1a, 1b), the lock bars (7a) are introduced into the lock sockets (7b). The locking bar (7a) then prised in between the flaps (13a, 13b) forcing them apart while the flaps (13a, 13b) still maintain its clamping force. The notches (14a, 14b) of the lock bars (7a) then engaged with lower the edges (15) of the flaps (13a, 13b) thus locking the piles together.

I claim: 
     
         1 . A joint for a concrete pile section comprising: a first end plate for connecting to the concrete pile; a plurality of spaced apart lock bars  7   a  attached to and extending substantially perpendicular to the first pile section  1   a ; a plurality of spaced apart lock sockets  7   b  attached to and extending substantially perpendicular to the end plate of pile section  1   b , wherein each of the plurality of lock sockets  7   b  has a cavity portion which are axially aligned with the lock bars  7   a  when in locked position; notches  14   a ,  14   b  formed on the opposed sides of lock bars  7   a  engaged with the lower edges  15  of the flaps  13   a ,  13   b  thus locking the two pile sections together. 
     
     
         2 . The joint according to  claim 1 , wherein a portion of the lock bars  7   a  extends a distance into one of the lock sockets  7   b.    
     
     
         3 . The joint according to  claim 1 , wherein the lock bars  7   a  comprise notches  14   a ,  14   b  formed periphery to the lower end  14  in alignment with one side of the opposite side walls. 
     
     
         4 . The joint according to  claim 1 , wherein the lock sockets  7   b  comprise flaps  13   a ,  13   b  formed from the two opposite sides of the walls of the lock sockets  7   b  and bending axially toward the axis of the lock socket cavity. 
     
     
         5 . The joint according to  claim 1 , further comprising a step edge formed circumferentially at the insertion openings  6  of at least four lock bars  7   a  where they attach to the first end plate. 
     
     
         6 . The joint according to  claim 1 , further comprising at least one anchoring device attached to at least one of the plurality of lock bars  7   a  and at least one of the plurality of lock sockets  7   b , wherein at least one anchoring device extends substantially perpendicular to the end plates  3   a ,  3   b  respectively. 
     
     
         7 . The joint according to  claim 1 , wherein the plurality of lock bars  7   a  are square or cylindrical in cross-section. 
     
     
         8 . The joint according to  claim 1 , further comprising the notches  12   a , and  12   b  of the locking bars  7   a  slightly tilted away from the axis. 
     
     
         9 . The joint according to  claim 7 , wherein the notches  12   a ,  12   b  are formed at the opposed sides of the locking bars  7   a.    
     
     
         10 . The joint according to  claim 1 , wherein each of the plurality of the lock bars  7   a  comprised a shoulder  10  formed at the upper end where the lock bars can be attached precisely to the end plate  3   a  by slotting through a hole  7  formed through the end plate  3   a.    
     
     
         11 . The joint according to  claim 1 , wherein the distance  10   a  of each of the plurality of locking bars  7   a  from the larger external surface of the end plate  3   a  to the notches  12   a ,  12   b  of the locking sockets  7   b  shall at least be equal to the distance  10   b  from the larger external surface of the end plate  3   b  to the lower edges of the flaps  13   a ,  13   b  or slightly longer by a 10 th  of a millimetre to a millimetre. 
     
     
         12 . The joint according to  claim 1 , further comprising a protective sheath  11  for inserting over the lock sockets  7   b  to prevent the ingress of concrete into the socket cavity during casting. 
     
     
         13 . The joint according to  claim 7 , wherein locking bars  7   a  and locking sockets  7   b  are substantially square in cross-section. 
     
     
         14 . The joint according to  claim 7 , wherein each of the plurality of the notches  14   a ,  14   b  shall slightly be tilted away from the axis of the lock bar  7   a  to be in synch with the angle of the lower edges  15  of the flaps  13   a ,  13   b , when in locking position. 
     
     
         15 . The joint according to  claim 1  comprise arrow indicators  17   a ,  17   b  shown on the visible side of the skirt  12   a ,  12   b  to assist in correct positioning of the joint components  2   a ,  2   b  in relation to one another. 
     
     
         16 . The joint according to  claim 7  wherein locking bars  7   a  are substantially cylindrical in cross-section throughout. 
     
     
         17 . The joint according to  claim 1  wherein the lock sockets  7   b  comprised at least a pair of flaps  13   a ,  13   b  formed on the opposed sides of the lock sockets  7   b  and bending inward toward the axis of the lock socket cavity.