Teacher Toolbox - The Purpose of this Section
This Apply section will help students understand how structure stability is applied in the real world by analyzing skyscrapers. The questions on this page can be explored as a group by facilitating a class discussion or individually having students write their ideas in their engineering notebooks. This can be used as a summative assessment such as a homework assignment or in-class formative assessment. Click here (Google Doc/.docx/.pdf) for the individual engineering notebook rubric and here (Google Doc/.docx/.pdf) for the collaboration rubric. The Motivate Discussion section provides questions to get students thinking about how structure stability can be useful.
Strength and Shape are Important
Seeing buildings tall enough to pierce through the clouds is awe-inspiring. As technology improves, humans build skyscrapers that are even taller than before.
Building tall buildings means overcoming gravity. Early humans used very heavy materials like stone to make strong buildings. Stone buildings cannot be skyscrapers though, because the structure cannot support that much weight. Inventions like steel and concrete, and techniques for using them together in building foundations allow buildings to reach skyscraper heights.
The shape of the building also matters. In the picture, you can see that the buildings are never wider at the top than at the bottom. A building's base needs to support the weight and also stay balanced. Natural events such as wind and earthquakes could cause the building to sway. Buildings with a wider top than their base could topple over! They must be strong and also stable to stand upright for a long time.
Motivate Discussion - Skyscrapers
Skyscrapers are seen in the majority of major cities and are extraordinary pieces of architecture. Prompt your students to discuss why the stability of a skyscraper is important.
Q: What factors could cause a skyscraper to be unstable?
A: Possible answers can include the skyscrapers shape, weight (materials) and strength (reinforcement).
Q: Describe the shape of skyscrapers that you have seen either in person or from pictures.
A: Possible answers can include a pyramid, rectangle and square. The students should be able to note that the top of the skyscraper cannot be wider than the bottom because it might cause it to become unstable (top heavy) and fall over.
Q: Are there rules for how high a skyscraper can be?
A: Rules vary by state and country. However, some rules do exist for how high a skyscraper can be so that it does not affect air traffic and flight patterns. Another point to consider is that extremely tall skyscrapers may not be worth the money to developers.