The Science of Architecture

How forces act on buildings & how buildings resist them

What Forces Affect Buildings?

• Gravity Forces

• Lateral Forces

• Temperature

Gravity Forces – Live Loads

• People

• Furniture

• Equipment

• Snow

Gravity Forces – Live Loads

• People

• Furniture

• Equipment

• Snow

Gravity Forces – Dead Loads

• Building structure

Substructure

Foundations

Below Grade Sp.

Gravity Forces – Dead Loads

• Building structure

Superstructure

Columns

Beams

Walls

Roof

Lateral Forces

• Wind

• Seismic

• Waves

Lateral Forces – Wind Loads

• Act horizontally and sometimes upward

• Can cause buildings to sway back and forth

• Buildings must be designed to resist these forces

Lateral Forces – Seismic Loads

• Violently shakes ground back and forth

• Can cause severe structural damage

• Buildings must be designed to absorb forces

Lateral Forces – Wave Loads

• Constant and tremendous force at base of building

• Can push superstructure off of foundation

• Buildings must be designed to allow waves to penetrate and go through structure

Forces Due to Temperature

• Expansion

• Contraction

Forces Due to Temperature• Expansion

– When a material heats up it can elongate or expand causing failure or damage to places where beams and columns connect.

• Contraction– When a material gets

cold it can shrink or contract also causing the same type of failure at connections.

Building Structure

• Superstructure– Beams– Columns– Walls– Roof

• Substructure– Foundation– Basement

Building Structure

• Beams– Resist a load or force

applied perpendicular to the beam. The beam bends to resist the force.

– The top of the beam is pushing together in “compression”.

– The bottom of the beam is pulling apart in “tension”.

– The strength of beams depend on two factors

• Strength of material

• Shape of the beam

Building Structure – Beam Diagram

Building Structure

• Columns– Resist a load or force

applied parallel to the column

– The columns resists the load in “compression”.

– The columns can also bend due to lateral loads.

– A column is really just a beam that is vertical or standing straight up.

Building Structure - Column Diagram

Building Structure - Connections

• Beams and Columns are connected together in different ways to form a “rigid” structure.

• These types of connections are one major way that buildings resist forces that act upon them.

Building Structure - Trusses

• A truss is a collection of structural members connected using “triangulation”. This method allows for a very lightweight and rigid structure that is commonly used in buildings and bridges.

Building Structure – Truss Diagram

Building ExamplesPyramids of Giza, Egypt

Building ExamplesThe Parthenon, Greece

Building ExamplesGothic Cathedral – St. Patricks’s, NYC

Building ExamplesEiffel Tower, Paris

Building ExamplesWorld Trade Center Towers

Building ExamplesJohn Hancock Building, Chicago

Building ExamplesSears Tower, Chicago

Building ExamplesPetronas Towers, Kuala Lumpur, Malaysia

Building ExamplesTaipei 101, Taipei, Taiwan

Building ExamplesBurj Dubai Tower, Dubai, UAE

World’s Current Tallest Buildings

World’s Tallest Buildings Timeline

Let’s Build!

Brian M. Taylor, AIABrian M. Taylor Architects P.C.