Wooden trussed structural systems, such as frameworks, bridges, floors

Abstract

A wooden trussed structure includes beams which are constructed from at least three elementary planks, nailed together. The plank located in the central part is offset relatively to the ends of the lateral planks, so as to form thereat, tenons and/or mortises for inserting, at the junction forming a node, a panel-type reinforcement, positioned in the core, and wherein the shearing surfaces correspond to the lateral surfaces at each node. The panel includes a wooden structural element such as a micro-lath or plywood as a plate-type solid web.

1 . A system for trussed wooden structures, with parallel members or in the shape of a triangle, for producing frameworks, bridges, floors, consisting of beams ( 1 , 2 , 3 ; 4 ,M)-( 6 , 7 , 8 , 9 ) made up of at least three elemental planks ( 10 , 11 , 12 , 14 , 15 )-( 21 , 22 , 23 ) nailed together, characterized in that: 
 the elemental planks that make up each beam are of the same thickness;    the plank ( 10 , 15 )-( 21 ) located in the central part is offset with respect to the ends of the lateral planks ( 11 , 12 , 14 )-( 22 , 23 ), this being in such a way as to form, at this point, tenons ( 16 ) and/or mortises ( 13 - 24 ) making it possible to include, at the junction zones forming nodes, a reinforcement ( 15 ) ( 17 ) ( 20 ) of the “panel” type, which is positioned in the web, and the shear surfaces of which correspond to the lateral surfaces at each node, said panel being made up of a structural wooden element of the “thin strip” or “ply” type allowing the bearing zone to be stiffened, operating like a solid rib of the “plate” type.    
     
     
         2 . The structural system as claimed in  claim 1 , characterized in that the plank ( 10 - 15 )-( 21 ) located in the central part consists of elemental planks placed end to end or spaced apart so as to form a mortise capable of accommodating a reinforcement of the “panel” type.  
     
     
         3 . The structural system as claimed in one of claims  1  and  2 , characterized in that the number of planks involved in making up each beam is an odd number and is greater than three, for example five, a reinforcement being positioned at each node in the even-numbered layers.  
     
     
         4 . The structural system as claimed in one of  claims 1  to  3 , characterized in that the reinforcing plate consisting of a structural wooden panel constitutes the central plank ( 15 ) of the beams that make up the posts ( 3 ) of a trussed structure with parallel members.