Flotation device

Abstract

A flotation device is disclosed having first and second spaced-apart, elongated, substantially rigid structural members and a plurality of buoyancy tubes held in compression between the first and second structural members. The compression connection between the ends of the buoyancy tubes and the sides of the structural members in this configuration can improve the structural integrity of the flotation device. The structural members can be made of glue-laminated timber, which has high strength and stability. The buoyancy tubes can be made of high-density polyethylene. A deck structure can be supported on top of the first and second structural members. Thus, thermal welding of the deck structure to the buoyancy tubes typically can be avoided. A flotation assembly also is disclosed including two flotation devices connected by a flexible hinge assembly.

1 . A flotation device comprising: 
 first and second spaced-apart, elongated, substantially rigid structural members;    a plurality of buoyancy tubes positioned between the first and second structural members and oriented substantially perpendicular to the first and second structural members; and    a plurality of tensioning members secured to the first and second structural members such that the buoyancy tubes are held in compression between the first and second structural members.    
   
   
       2 . The flotation device of  claim 1 , wherein the first and second structural members extend substantially the entire length of the flotation device.  
   
   
       3 . The flotation device of  claim 1 , wherein the first and second structural members are sized to completely cover the ends of the buoyancy tubes.  
   
   
       4 . The flotation device of  claim 1 , wherein the first and second structural members comprise glue-laminated timber.  
   
   
       5 . The flotation device of  claim 1 , wherein the buoyancy tubes comprise high-density polyethylene.  
   
   
       6 . The flotation device of  claim 1 , wherein the tensioning members comprise metal rods.  
   
   
       7 . The flotation device of  claim 1 , wherein the tensioning members are positioned such that they would support the buoyancy tubes if the buoyancy tubes were not held in compression between the first and second structural members.  
   
   
       8 . The flotation device of  claim 1 , wherein the buoyancy tubes house respective foam cores.  
   
   
       9 . The flotation device of  claim 1 , wherein the first and second structural members are sized to partially cover the ends of the buoyancy tubes.  
   
   
       10 . The flotation device of  claim 1 , wherein the buoyancy tubes are arranged in parallel, transversely extending rows, each row having at least first and second buoyancy tubes positioned end-to-end and separated by an intermediate structural member extending substantially perpendicular to the rows of buoyancy tubes.  
   
   
       11 . The flotation device of  claim 1 , wherein the flotation device does not include any shear-resisting elements placed in compression between the first and second structural members that are not buoyancy tubes, tensioning members or intermediate structural members.  
   
   
       12 . The flotation device of  claim 1 , wherein the tensioning members extend through the first and second structural members and have nuts tightened on their outer end portions to place the buoyancy tubes in compression between the first and second structural members.  
   
   
       13 . The flotation device of  claim 1 , further comprising a wale held in compression against an outer surface of the first or second structural member.  
   
   
       14 . The flotation device of  claim 1 , wherein the cross-sectional area of at least one of the buoyancy tubes is from about 200 to about 100,000 square inches.  
   
   
       15 . The flotation device of  claim 1 , further comprising a deck structure supported above the first and second structural members.  
   
   
       16 . The flotation device of  claim 15 , having substantially no supports for the deck structure located between the first and second structural members that are not intermediate structural members.  
   
   
       17 . The flotation device of  claim 15 , further comprising a utility tube positioned between at least a portion of the buoyancy tubes and the deck structure.  
   
   
       18 . A flotation device comprising: 
 first and second spaced apart, elongated, substantially rigid structural members comprising glue-laminated timber; and    a plurality of buoyancy tubes positioned between the first and second structural members and extending in a direction that intersects the first and second structural members.    
   
   
       19 . The flotation device of  claim 18 , wherein the buoyancy tubes comprise high-density polyethylene.  
   
   
       20 . The flotation device of  claim 18 , wherein the buoyancy tubes are arranged in parallel, transversely extending rows, each row having at least first and second buoyancy tubes positioned end-to-end and separated by an intermediate structural member extending substantially perpendicular to the rows of buoyancy tubes.  
   
   
       21 . The flotation device of  claim 18 , wherein the cross-sectional area of at least one of the buoyancy tubes is from about 200 to about 100,000 square inches.  
   
   
       22 . The flotation device of  claim 18 , further comprising a deck structure supported above the first and second structural members.  
   
   
       23 . The flotation device of  claim 22 , having substantially no supports for the deck structure located between the first and second structural members that are not intermediate structural members.  
   
   
       24 . The flotation device of  claim 18  in combination with another flotation device, the flotation devices interconnected by a flexible hinge assembly.  
   
   
       25 . The combination of  claim 24 , wherein the flexible hinge assembly comprises at least a piece of a flexible belting material connected to each flotation device.  
   
   
       26 . A flotation device comprising: 
 a plurality of buoyancy tubes; and    means for holding the buoyancy tubes in compression.    
   
   
       27 . A flotation assembly comprising: 
 a first flotation device comprising a plurality of buoyancy tubes held in compression between structural members oriented substantially perpendicular to the buoyancy tubes;    a second flotation device comprising a plurality of buoyancy tubes held in compression between structural members oriented substantially perpendicular to the buoyancy tubes; and    a flexible hinge assembly attaching the first flotation device to the second flotation device, wherein the flexible hinge assembly comprises an elastomeric material.    
   
   
       28 . The flotation assembly of  claim 27 , wherein the flexible hinge assembly further comprises plates secured to substantially vertically oriented major planar surfaces of the structural members of the first and second flotation devices.  
   
   
       29 . The flotation assembly of  claim 28 , wherein the flexible hinge assembly further comprises brackets secured to the plates, and the elastomeric material connects a bracket of the first flotation device to a bracket of the second flotation device.  
   
   
       30 . The flotation assembly of  claim 27 , wherein the flexible hinge assembly comprises a belting material having substantially horizontally oriented major planar surfaces and a gap-filling deck plank mounted above the belting material.  
   
   
       31 . The flotation assembly of  claim 30 , wherein the gap-filling deck plank is secured to the belting material with at least one bolt and the flexible hinge assembly further comprises a spacer positioned between the gap-filling deck plank and the belting material.  
   
   
       32 . A method for making a flotation device comprising, 
 positioning a plurality of buoyancy tubes between and substantially perpendicular to a pair of structural members;    securing a plurality of tensioning members to the first and second structural members; and    tightening the tensioning members to place the buoyancy tubes in compression between the structural members.