A building's structure must withstand physical forces or displacements without danger of collapse or without loss of serviceability or function. The stresses on buildings are withstood by the buildings' structures.
Buildings five stories and less in height typically use a “bearing wall” structural system to manage dead and live load vertical forces. Vertical forces on the roof, floors, and walls of a structure are passed vertically from the roof to the walls to the foundation by evenly spreading the loads on the walls and by increasing the size and density of the framing or frame structure from upper floors progressively downward to lower floors, floor-to-floor. For ceilings and floor spans, trusses are used to support loads on the ceilings and floors and to transfer these loads to walls and columns.
Where vertical bearing elements are absent, for example at window and door openings, beams are used to transfer loads to columns or walls. In buildings taller than five stories, where the walls have limited capacity to support vertical loads, concrete and/or structural steel framing in the form of large beams and columns are used to support the structure.
Lateral forces (e.g., wind and seismic forces) acting on buildings are managed and transferred by bracing. A common method of constructing a braced wall line in buildings (typically 5 stories or less) is to create braced panels in the wall line using structural sheathing. A more traditional method is to use let-in diagonal bracing throughout the wall line, but this method is not viable for buildings with many openings for doors, windows, etc. The lateral forces in buildings taller than five stories are managed and transferred by heavy steel let-in bracing, or heavy steel and/or concrete panels, as well as structural core elements such as concrete or masonry stair towers and elevator hoistways.
There is a need for a panelized and modular system for constructing and assembling buildings without relying on concrete and/or structural steel framing, heavy steel let-in bracing, and heavy steel and/or concrete panels.