Logical Sequence: 1. Framed Structures -Introduction: Structural function Structural types and a definition of framed structure 2.Building components of the structure 3.Structural material -Wood -Concrete -Steel 2. Examples
Structural function requirements Physical actions Mass Inertia forces Dimensional changes Stable Resist basic charges Overload withstand foreseeable Earthquakes structural objective Limiting deformations Vibrations prevent The passage of time.
Structural typology We are refering to its geometry, depending mainly on its use, taking into account the maximum material efficiency, and minimum obstruction space. Burnham pavilion Chicago ILLINOIS Museum of contemporary culture London ENGLAND
Framed Structure A framed structure in any material is one that is made stable by a skeleton that is able to stand by itself as a rigid structure without depending on floors or walls to resist deformation. Materials such as wood, steel, and reinforced concrete, which are strong in both tension and compression.
The surface elements Function is to cover the surface The constituent elements
Horizontal linear elements For concrete to steel is the width and thickness Beams
Structural material the tensile modulus elasticity
heavy timber frame, heavy timber frame, The heavy timber frame, in which large posts, spaced relatively far apart, support thick floors and roof beams.
In the heavy-timber system, the beams are strong enough to allow the upper story and roof to project beyond the plane of the ground-floor posts, increasing the space and weather protection. The members are usually exposed on the exterior. heavy timber frame, heavy timber frame,
American light wood frame (balloon frame) American light wood frame (balloon frame) Composed of many small and closely spaced members that could be handled easily and assembled quickly by nailing instead of by the slow joinery and dowelling of the past. Construction is similar in the two systems, since they are both based on the post-and-lintel principle. Posts must rest on a level, waterproof foundation, usually composed of masonry or concrete, on which the sill (base member) is attached
The light frame The light frame, however, is sheathed with vertical or horizontal boarding or shingling, which is jointed or overlapped for weather protection. Sheathing helps to brace as well as to protect the frame, so the frame is not structurally independent as in steel frame construction. The light frame system has not been significantly improved since its introduction, and it lags behind other modern techniques The light frame, however, is sheathed with vertical or horizontal boarding or shingling, which is jointed or overlapped for weather protection. Sheathing helps to brace as well as to protect the frame, so the frame is not structurally independent as in steel frame construction. The light frame system has not been significantly improved since its introduction, and it lags behind other modern techniques
Steel framing Steel framing is based on the same principle but is much simplified by the far greater strength of the material, which provides more rigidity with fewer members. The load-bearing capacity of steel is adopted for buildings many times higher than those made of other materials. Because the column and beam are fused by riveting or welding, stresses are distributed between them, and both can be longer and lighter than in structures in which they work independently as post-and-lintel.
Steel Framing Since structural steel must be protected from corrosion, the skeleton is either covered by curtain walls or surfaced in concrete or, more rarely, painted. The steel frame is used also in single story buildings where large spans are required The simple cube then can be abandoned for covering systems employing arches, trusses, and other elements in a limitless variety of forms in order to suit the functions of the building.
EXAMPLES Tower cranes and communication towers the Eiffel Tower (Paris, Francia) the Sullivan Center (Chicago, USA)