Tank shell for an outer lng containment tank and method for making the same

Abstract

A shell for an outer LNG containment tank and a method of making the shell from a plurality of precast reinforced concrete shell elements are described. The shell elements having a precast concrete body to which are anchored a radially inwardly facing liner plate and a pair of circumferentially spaced apart side plates which depend radially outwardly from the liner plate. The shell elements can be arranged upon a ring beam with side plates abutting one another. The side plates are welded together to form radially and vertically extending stiffener ribs which are circumferentially spaced around the shell. As these stiffener ribs provide great structural support, the shell can be constructed with minimal or no cast in place structural joints being needed to construct the shell. Ideally, the shell elements have bottom base plates welded to a ring beam or foundation and top end plates that are welded together to form an annular ring thus enhancing the structural strength of the shell. A roof can be mounted to the shell to create an outer LNG containment tank.

1 . A method for constructing a shell for an outer LNG containment tank, the method comprising:
 providing a plurality of precast reinforced concrete shell elements, at least some of the shell elements having a precast concrete body to which are anchored a radially inwardly facing liner plate and a pair of radially extending and circumferentially spaced apart side plates which depend from the liner plate;   juxtaposing the shell elements upon a ring beam with side plates abutting one another; and welding abutting side plates together to at least partially form the shell and to form radially extending stiffening ribs which are circumferentially spaced around the periphery of the shell.   
   
   
       2 . The method of  claim 1  wherein:
 at least some of the shell elements include a base plate and a top end cap plate;   and the base plates are welded to the ring beam and the top end cap plates are welded to one another to form an annular ring of top end cap plates.   
   
   
       3 . The method of  claim 1  wherein:
 the liner plates and side plates cooperate to form a continuous inner radial membrane to the shell.   
   
   
       4 . The method of  claim 1  wherein:
 at least some of the shell elements have mechanically interlocking surfaces and the at some of the shell elements interlock with one another before being welded together.   
   
   
       5 . The method of  claim 4  wherein:
 at least some of the interlocking surfaces include cooperating projections and receptacles.   
   
   
       6 . The method of  claim 1  wherein:
 the shell includes at least two circumferentially extending and vertically arranged courses of shell elements which are welded together to form at least a portion of the shell.   
   
   
       7 . The method of  claim 1  further comprising:
 constructing the shell to include a shell access opening therein to allow access within the shell.   
   
   
       8 . The method of  claim 7  further comprising:
 sealing the shell access opening with at least one temporary liner plate; pressurizing the inside of the shell to air lift a roof assembly to the top of the shell;   mounting the roof assembly to the shell;   unsealing the shell access opening to access the interior of the shell to construct an inner tank while roof elements are welded to the roof assembly to form a roof atop the shell;   and permanently sealing the shell access opening after the inner tank is constructed.   
   
   
       9 . The method of  claim 7  further comprising: casting in place a concrete body which anchors to the at least one temporary liner plate to effect the permanent sealing of the shell access opening. 
   
   
       10 . The method of  claim 7  further comprising:
 permanently sealing the access opening utilizing at least one temporary liner plate, the temporary liner plate being part of a precast reinforced concrete shell element.   
   
   
       11 . A shell for an outer LNG containment tank, the shell comprising:
 a plurality of precast reinforced concrete shell elements, at least some of the shell elements having a precast concrete body to which are anchored a radially inwardly facing liner plate and a pair of radially extending and circumferentially spaced apart side plates which depend from the liner plate;   wherein the at least some of the shell elements are arranged circumferentially with abutting side plates being welded together to at least partially form a shell and to form radially extending stiffening ribs which are circumferentially spaced about the periphery of the shell.   
   
   
       12 . The shell of  claim 11  wherein:
 at least some of the shell elements further include bottom base plates which are welded to a ring beam to provide support to the shell.   
   
   
       13 . The shell of  claim 11  wherein:
 at least some of the shell elements further include top end cap plates which are welded to one another to form an annular ring of end cap plates.   
   
   
       14 . The shell of  claim 11  wherein:
 the liner plates and side plates cooperate to form a continuous inner radial membrane to the shell.   
   
   
       15 . The shell of  claim 11  wherein:
 at least some of the shell elements have mechanically interlocking surfaces and the at least some of the shell elements interlock with one another.   
   
   
       16 . The shell of  claim 15  wherein:
 at least some of the interlocking surfaces include cooperating projections and receptacles.   
   
   
       17 . The shell of  claim 11  wherein:
 the shell includes at least two circumferentially extending and vertically arranged courses of shell elements which are welded together to form at least a portion of the shell.   
   
   
       18 . The shell of  claim 11  wherein:
 the shell has an shell access opening formed therein; and the shell access opening is sealed by at least one cast in place shell element having a liner plate which cooperates with the liner plates and sides plates of the precast shell elements to seal the access opening.   
   
   
       19 . The shell of  claim 11  wherein:
 the shell has an shell access opening formed therein; and the shell opening is sealed by at least one precast shell element having a liner plate, the at least one precast shell element cooperating with other liner plates and sides plates of the shell to seal the access opening.   
   
   
       20 . A shell element for constructing the shell of an outer LNG containment tank, the shell element comprising:
 a precast reinforced concrete body to which are anchored a radially inwardly facing liner plate and a periphery formed by a pair of vertically extending circumferentially spaced apart side plates, a bottom base plate and a top end cap plate;   wherein a plurality of the shell elements may be arranged in circumferential abutment and the side plates welded together to form radially extending stiffener ribs and the liner plates form part of radial inwardly facing shell membrane.