alias STRUCTURE UNDERSTANDING the LOAD CARRYING SYSTEM of BUILDINGS

SYSTEM Method of approach to understanding Collection of interrelated elements Various aspects of elements and relationships Problems related to the whole system

STRUCTURE Multiple structures in a system. Abstract notion describing interrelationship of elements Many different representations (verbal, graphical, mathematical).

MY FAMILY SYSTEM Mother Father Foster mother MeBrother Sister Brother in Law Sister in Law Wife Nephew SonDaughterNiece Daughter in Law Son in Law Granddaughter Grandson

STRUCTURE of MARRIAGES MATHEMATICAL REPRESENTATION

PARENTAGE STRUCTURE Mother Father Foster mother MeBrother Sister Brother in Law Sister in Law Wife Nephew SonDaughterNiece Daughter in Law Son in Law Grandson Granddaughter GRAPHICAL REPRESENTATION

A SIMPLE BUILDING PLAN Exterior Corridor Reception Secretary Boss Room 1 Hall Room 2 Room 3 Room 4

CIRCULATION STRUCTURE Reception Secretary Boss Corridor Exterior Room 1 Hall Room 2 Room 3 Room 4

WHY BUILDINGS? Security (predators, pests, enemies, etc.) Meso-environment (thermal, acoustic, light)

PROBLEMS in BUILDINGS Problem specific structures Problems and factors Nearly all elements involved

HUMAN FACTORS Cultural (meanings, use patterns, etc.) Psychological (spatial perception, spatial cognition) Physiological (thermal comfort) Social (spatial layout)

ENVIRONMENTAL FACTORS Climatic (thermal, radiation, wind, rain, snow, etc.) Topographical (slopes, vegetation) Geological (gravitation, earthquakes, materials, foundations) Economic (materials, labor, finance)

MECHANICAL FACTORS Foundations Mechanics (forces and motions) Loads (gravitation, wind, earthquakes)

LOAD CARRYING SYSTEM (LCS) Elements + connectivity structure STRUCTURE of building Structural problems

A SIMPLE BUILDING LCS Slab Beam 1 Beam 2 Beam 3 Beam 4 Column 1 Column 2 Column 3 Column 4 Wall 1 Wall 2

BUILDING ELEMENTS C1C2 C3C4 Slab Wall 1 Wall 2 B1 B2 B3 B4

STRUCTURE of CONNECTIVITY Slab B1B2B3B4 Wall 1Wall 2 C1C2C3 C4 Edge connection End connection

STRUCTURAL REQUIREMENTS of LCSs Restraint (sufficient members and supports to provide for equilibrium) Strength (sufficient material to prevent rupture) Rigidity (sufficient resistance to deformation) Ductility (sufficient capacity for energy absorption)

COMPATIBILITY REQUIREMENTS of LCSs Spatial layout (e.g. hotels, bearing walls) Materials (e.g. masonry and vaults) Services (integration of services) Construction (e.g. bearing walls, integral forms, tower cranes)

STRUCTURAL BEHAVIOR Displacements/deformations Load Internal force Load Internal forces Energy storage Language of description is mechanical.

UNDERSTANDING BEHAVIOR of LCSs Modeling of LCS Prediction of loads Analysis of mechanical forms Understanding in terms of basic modes

DIRECTION of PREDOMINANT LOAD Vertical (gravitation) Horizontal (wind) Combination (earthquake)

GEOMETRIC FORM 3D forms - solid, systems of 1D and 2D forms Dimensionality 1D forms - rod, planar curve, spatial curve 2D forms - plane, surface, systems of 1D forms Orientability

MECHANICAL FORM Combination of geometric form and load Orientation Load Geometric Form Mechanical form = Oriented and loaded geometric form

MECHANICAL FORMS (BEAM and COLUMN) Geometric Form = ROD Load Orientation Load Orientation BEAMCOLUMN

MECHANICAL FORMS (ARCH and CURVED BEAM) Geometric Form = PLANAR CURVE Load ARCH LoadOrientation Load Orientation CURVED BEAM

Arch

Curved Beam

Spatial Curved Beam

MECHANICAL FORMS (SLAB and WALL) Geometric Form = PLANE Load WALL LoadOrientation Load Orientation SLAB

Slab

Folded Plate

MECHANICAL FORMS (SHELL) Load

Shell

Dome

UNDERSTANDING SPECIFIC BUILDING LCS’s Resolve hierarchy of structural problems Determine scale of problem (overall building, breakdown of main structure, detail elements) Resolve structure of elements Recognize the MF of elements

World Trade Towers

SKYSCRAPER (overall building scale) Gravitation MF = COLUMN Wind or Earthquake MF = BEAMGF = ROD

SKYSCRAPER (main structure scale) GF = PLANE Gravitation MF = SLAB MF = WALL Gravitation MF = WALL Earthquake

Sears Tower

SKYSCRAPER (detail scale) GF = PLANE GF = ROD Lateral Load MF = BEAM Weight Axial Load MF = COLUMN Axial Load Weight MF = SLAB

BEHAVIOR of the BEAM BENDING MOMENT SHEAR INTERNAL FORCES

BEHAVIOR of the COLUMN Compression Tension INTERNAL FORCES COMPRESSIVE AXIAL FORCE TENSILE AXIAL FORCE

BEHAVIOR of the COLUMN (BUCKLING) BENDING MOMENT INTERNAL FORCE Load

DESIGN for BENDING Provide material away from the center. I beam RC beam Provide the right kind of material.

DESIGN for SHEAR Truss Provide diagonals I beam Castella beam Welding

DESIGN for COMPRESSION AGAINST BUCKLING Provide this material away from the center. Provide the necessary material in axial form.

TWO BASIC PROBLEMS 1. Space enclosure. 2. Provision of horizontal levels. Planes of equal potential energy

CONCLUSION Look at a building LCS hierarchically. Identify the predominant loading. Identify the geometric form. Identify the mechanical form. Estimate the behavior.