How Engineers Prepare for The Big One

Review: California Faults Review of prior lessons on earthquakes SAN ANDREAS FAULT

Review: California Earthquakes 8 major earthquakes since 1800 Richter scale ranges from 6.6 to 7.9 Highest magnitude = 7.9 Fort Tejon, 1857 San Francisco, 1906 Most Expensive ($ Damage) Northridge, 1999—$15 billion Most deaths San Francisco, 1906—3000 Most recent earthquake in 1999 Discussion of major earthquakes in California Information from USGS

What do you think engineers do? How do we prepare? What do you think engineers do? Engineers work together to study the area of the building location to determine how safe the ground is to build on and if there are additional building requirements. People involved Civil engineers Earthquake engineers Geotechnical engineers (dirt!)

Lesson Goals Today we will learn: Building components Learn how certain Engineers Design buildings to survive an earthquake Stay within a supply budget Build efficiently and creatively! Today we will learn: Building components Building structure Plan and Design Earthquake Testing Redesign and Stability

Building Components STEP 1 JOINT (Dots or mini marshmallow) BEAM (Toothpick)

Building Structure STEP 1 STEP 2 1st cube = 8 Joints & 12 Beams BUILDING CUBE

Plan and Design Supply Inventory and Specs: Length of Beam (toothpick) [inches] Number of Beams Number of Joints (Dots & marshmallows) Hypothesis: Initial structure plan

Plan and Design “FOUNDATION” Recommend using Dots Students start off with building a cube or they can use other shape they like. The dots/gummies are placed on the foundation because they are the stronger material that can support the overlying weight. “FOUNDATION” Recommend using Dots

Plan and Design “BUILDING LAYOUT” Recommend using marshmallows The building layout can use marshmallows because they are lighter and are still pretty strong. “FOUNDATION” Recommend using Dots

Plan and Design Label the following: Use engineering paper to plan your building Plan and Design Label the following: Length and Width of the foundation Height of the building Label the number of levels HEIGHT They use the engineering paper to design their building. They draw a bird’s eye view of the foundation labeling length and width, and plan how tall they want their building layout to be—label weight and height. WIDTH LENGTH

Plan and Design “STABILITY” The state or quality of being stable, especially: Resistant to changing, breaking down, or moving. Measurement of reliability and dependability. “CROSS BEAM” Used to add stability to structure Case of the 3 bears If you add too few, your building will be weak and collapse If you add too many, your building will be heavy and collapse If you add just enough, your building will survive To create a cross-beam you use two chopsticks and a marshmallow. You put a marshmallow at the center of the toothpick and extend it using another toothpick. Just an FYI…

Earthquake Testing SURVIVAL! SHAKER [P earthquake waves] This is animated to show the shaking did not break the building. SHAKER [P earthquake waves]

Earthquake Testing REDESIGN! SHAKER [P earthquake waves] This is animated to show the shaking broke break the building and a redesign is required to make it stronger. SHAKER [P earthquake waves]

Building Restrictions Must be at least 1 foot tall Must fit inside green basket No new supplies!! 1 foot Inside basket

GO Plan and Design! Label the following: Use engineering paper to plan your building GO Plan and Design! Label the following: Length and Width of the foundation Height of the building Label the number of levels HEIGHT “CROSS BEAM” Used to add stability to structure Too few, your building will be weak Too many, your building will be heavy Just enough, your building will survive WIDTH LENGTH

CLEAN-UP! CLEAN TOOTHPICKS IN THE BAG DIRTY TOOTHPICKS IN THE TRASH PUT THE BAG WITH TOOTHPICKS AND EMPTY MARSHMALLOW BAG BACK IN YOUR GREEN BASKET