Pre-stressed intersecting modular truss and concrete decking floor system

Abstract

A structural floor system generally consisting of a grid of intersecting modular trusses, pre-stressed wire strand system and concrete decking. U or C-shaped cold-formed or hot-rolled profiles are used to form the prefabricated modular trusses. Assembling the trusses in two-way creates a grid of intersecting trusses. By running the wire strand from the truss grid, the tension force applies to the floor system. A pre-stressed truss grid accompanying with a reinforced concrete slab above, forms a composite structural floor system which is ideal for floor covering in wide spans in multi-story constructions. A method for assembling such a system is also disclosed.

1 . A pre-stressed composite structural floor system comprising
 a) a plurality of intersecting truss girders, wherein each truss itself comprising several modular low-length truss units   b) a wire strand system,   c) an in-situ poured reinforced concrete slab,   
     
     
         2 . The structural floor system defined in  claim 1 , wherein each of the said truss unit comprising the upper and lower cord joined by a web extended between and connecting the said upper and lower cord together, the web comprising at least two vertical and a diagonal member with certain shape and certain length from cold-formed or hot-rolled steel. 
     
     
         3 . The structural floor system defined in  claim 1 , wherein each of the said truss unit, the upward projected upper chord is punched, and holes are created in the longitudinal direction with a regular pattern to ensure the passage of concrete and provide the composite action. 
     
     
         4 . The structural floor system defined in  claim 1 , wherein each modular truss unit combined with another to create the truss girders by splicing assemblies in the upper and lower cord. 
     
     
         5 . The structural floor system defined in  claim 4 , wherein said splicing assemblies comprises the cross-shaped plates fixed the upper and lower cord member by welded or bolted connection. 
     
     
         6 . The structural floor system defined in  claim 1 , wherein the wire strand system passes through the lower cord and diagonal member of each truss girder and fixed at the upper cord to introduce the pre-stress to a certain limit. 
     
     
         7 . The structural floor system defined in  claim 1 , wherein the wire strand has different area and size applied to impose the prestressed with respect to the total length and the configuration of the said truss girders. 
     
     
         8 . The structural floor system defined in  claim 1 , wherein truss girders have certain form of placement like parallel or perpendicular. 
     
     
         9 . The structural floor system defined in  claim 1 , wherein said truss girder has straight or curved shape of its longitudinal cross-section. 
     
     
         10 . A construction procedure of pre-stressed composite structural floor system comprises of
 a) Construction of modular truss units in a controlled environment and shipment to the field work   b) Assemblage of the said truss units on the ground to form girder trusses by said splicing assemblies   c) Lifting up the diagonal girder truss between two columns and then the other parallel shorter truss girders   d) Installation of the truss units on the other side to form a grid of intersecting trusses.   e) Imposing pre-stress to the truss grid by passing the wire strand through the trusses.   f) Establishing the formwork under the truss upper cord and pouring the concrete to embed the said cord in the topping reinforced concrete.   
     
     
         11 . The structural floor system according to  claim 1 , wherein another embodiment of the said system construction comprises of
 a) Construction of modular truss units in a controlled environment and shipment to the field work   b) Assemblage of the said truss units on the ground to form all parallel truss girders by said splicing assemblies   c) Installation of the truss units on the other side to form a grid of intersecting trusses.   d) Lifting up the said truss grid on the surrounding beams   e) Imposing pre-stress in the truss system by passing the wire strand through the trusses.   f) Establishment of formwork under the truss upper cord and pouring the concrete to embed the said cord in the topping reinforced concrete.