Building Earthquake- and Tsunami-Proof Structures in 6th Grade Science
In their Science unit on the Earth’s Structure, 6th Graders have been considering how and why the earth is constantly changing, what causes earthquakes and volcanoes and how engineers solve problems. After learning why earthquakes occur and how seismologists locate earthquake epicenters, 6th Graders turned their focus to how buildings are impacted by earthquakes – and how the acceleration of a structure during an earthquake is mitigated by the presence of a base isolation system.
In preparation for their Earthquake Structure Design Challenge, students researched what materials and shapes were used in the most effective earthquake-resistant structures. Working in pairs, 6th Graders then sketched and built an 8-inch earthquake-resistant structure using 20-30 straws, modeling clay for joints and a folder to attach as a base. They tested their designs on shake tables and collected data on the average acceleration of their structures, then reflected on the strengths and weaknesses of their models. Next, 6th Graders designed and built a base isolation system for their structures and repeated their acceleration trials. Comparing the two sets of data provided students with a better understanding of how a base isolation system affects the acceleration of the structure it supports, and allowed them to reflect on what the ideal design for an earthquake-proof structure would be.
Earthquakes can’t only pose a threat to structures by increasing their acceleration, but also by creating powerful tsunamis; after completing their Earthquake Structure Design Challenge, students looked at the elements commonly used to protect coastal houses from the impact of a tsunami, such as elevation, reinforced materials like concrete and steel, sea walls and vegetation. Working in small groups, students applied this knowledge as they made a small paper house, then redesigned the house or surrounding area using Legos, mini-sponges, toothpicks and other basic materials. Each group tested their completed tsunami-proofing solutions in a recreated coastline with strong waves and documented their observations.
Next, 6th Graders will turn their attention from the criteria and constraints of a successful design solution to take a closer look at the science of extreme weather.