Building Challenge

Your task is to design and build structure that can withstand a simulated earthquake.

You will be given glue and craft sticks after you get your design

What you’re up against…

• Earthquakes generate two types of waves– Primary, compressional or P waves: these

are the first energy waves to arrive. They travel at speeds up to 5.5 km/second (12,000 miles/hr). These are the least damaging of the seismic waves.

– Secondary, shear, or S waves are a second to arrive. They travel only through solids and travel at speeds of 3 km/second. These are more damaging than P waves.

Why worry about seismic waves?

• If the frequency of the seismic waves are close to the natural frequency of a building, the building with begin to vibrate.

• If that vibration continues, the building will sway and may even topple over.

What you get…

• Up to 150 craft sticks which you can/must cut into wood splints or toothpicks

• Styrofoam base

• Titebond glue

• Velcro to attach the base to the shaker table

Building Requirements

• Buildings must be at least 45 cm tall.• Buildings must at least 3 stories.• Each story must have a floor (not necessarily

solid).• The roof must be flat enough to hold a

standard red brick or some contraption.• The base of the building must have sides no

longer than 22.5cm and must have two sides be longer than the sticks themselves.

Design Considerations

Sample Wall Support:

Sample Trusses:

Design Considerations:

• Sample Floors with corner bracing or cross beams:

Joists

• Parallel, horizontal beams set from wall to wall to support the boards of a floor or ceiling.

• None of the materials are long enough to serve as joists alone. You will need glue several together to make one joist.

The First Step – The Design

• You and your group need to brainstorm some ideas about how best to design your building.– What kind of reinforcement will you use?– How solid do you want your floors to be?– Will all three levels have the same type of

reinforcement?

• Then you need to start to draw a diagram of the building on graph paper. All diagrams must be drawn to scale (figure out how much one square on the graph paper will represent).

The Explanation

• Your drawings will be turned in along with written support of your design. This document will outline the qualities and characteristics that will make the building resistant to earthquake damage.

• No building can occur before designs are approved by your teacher!

Grading your Final Plans

• All members of the group must turn in their own set of plans and their own explanation. The grade will be based on the following:– Appropriate and correct scale = 10 pts– Illustration of all details necessary = 10 pts– Correct count of materials = 5 pts– Neatness = 5 pts– Clear explanations of different structural elements

(must be typed up). = 20 pts

Grading your building

• Can hold at least 2 bricks on top = 20 points• Can withstand a quake = 20 points• Weight

– Team with the lightest building that can withstand a quake and load gets 5 bonus points.

– Team with the heaviest building will lose 5 points.

• Height– Team with the tallest building that can withstand a quake

and load gets 5 bonus points gets 5 bonus points.

• Neatness: things like no visible glue = 10 points• Creativity bonus = 5 points