Dome Info for Kids | AiDomes

This video explains how to construct a model of a geodesic dome from paper and gives a brief history of domes. To view the video, click on the white triangle in the middle.

Unlike buildings with flat roofs, which rely on regularly spaced columns for support (the bigger the roof, the more columns required), domed roofs are designed to provide the maximum amount of unobstructed covered space. With no internal support columns standing in the way, domed structures are well suited as places where people congregate, such as convention centers and sports venues.

In a traditional, hemispheric dome, a series of arches intersects at the crown. Here, forces move inward toward the center, pushing the halves of each arch together and making the resulting dome rigid. The great weight of concrete material, however, creates downward and outward forces near the bottom of the dome that must be balanced by upward and inward forces to prevent the dome from collapsing. In a well-designed dome, the material from which it is built provides enough support to balance the downward force of the load. But what can be done to minimize the outward push, or tension, in the lower portion of the structure? Two things: encircle the dome’s rim with a steel cable or chain, or build heavy concrete step rings around the dome’s perimeter to keep it in compression, or pushed in.

Over time, engineers have devised new ways to manage forces in domes, employing lighter materials and using less of them. By using a smaller, self-supporting internal dome as a base, fourteenth-century engineers discovered they could build steeper, more impressive outer domes that weighed just a fraction of what the inner dome weighed. London’s St. Paul’s Cathedral and the U.S. Capitol building each have “false”p double domes, the outermost of which is little more than a shell. Engineers have also turned to new materials like iron to construct domes that are more supportive and considerably lighter than stone or concrete domes of the same size.

In the mid-twentieth century, space frames, which are assemblies of lightweight tubular steel struts, were adapted to create a model for the most efficient and economical means of enclosing large spaces: the geodesic dome. This self-supporting spherical structure has inspired the wide-spanning tension domes that have today become the design of choice for sports venues.

Questions for Discussion

  • How is the room you are in like a dome? If it is not curved, is it a dome anyway?
  • Use everyday materials to build a dome that will cover an object in your house, such as a plant or cake or some delicate item. What forces act on your dome? How does your structure withstand these forces?
  • Use a sketch to show where tension and compression forces are operating in the domes you chose in the interactive challenge for the baseball stadium, the greenhouse, and the Capitol Building.

You and Your Classmates Can Make a Geodesic Dome

Out of Newspaper or Cardboard

To view a web site that shows cardboard and transparent plastic domes that kids have built: http://www.domebook.com

The website highlights kid-made domes and shows some of their creations. The students start by constructing paper models (viewers can download models of two domes from the “Domes” page of the site), then construct full-size domes using cardboard or wooden dowels and plastic sheeting. The site leads to a book, Domebook: How to Construct Cardboard Geodesic Play-Domes, that shows how to build the domes.

building a geodesic dome out of newspaper

The following Geodesic Dome info came from the web site: http://pbskids.org/zoom/activities/sci/geodesicdome.html

You can build a giant geodesic dome out of newspaper. First, gather some friends to help you out.

Geodesic Dome

Sent in by:
Ms. Hsu’s 3rd grade class of Brookline, MA
For this ZOOMsci, you da dome!

Materials Needed
  • Newspaper
  • Masking tape
  • Measuring tape
  • Markers for decorating
Instructions
  1. Geodesic domes are made up of a pattern of connected triangles and are very strong. You can build a giant geodesic dome out of newspaper. First, gather some friends to help you out.
  2. Next, stack three flat sheets of newspaper together. Starting in one corner, roll the sheets up together as tightly as you can to form a tube. When you reach the other corner, tape the tube to keep it from unrolling. Repeat until you have 65 tubes.
  3. Now cut down the tubes to make 35 “longs” and 30 “shorts”.
  4. To make the “longs”, cut off both ends of a tube until it is 71 cm long. Use this tube as a model to create 34 more longs. Be sure to mark all the longs clearly in some way, such as with colored tape, so you can tell them apart from the shorts.
  5. To make the “shorts”, cut off both ends of another tube until it is 66 cm long. Use this tube as a model to create 29 more shorts.
  6. Decorate the tube if you like.
  7. Next, tape 10 longs together to make the base of the dome.
  8. Tape a long and a short to each joint. Arrange them so that there are two longs next to each other, followed by two shorts, and so on.
  9. Tape the tops of two adjacent shorts together to make a triangle. Tape the next two longs together, and so on all the way around.
  10. Connect the tops of these new triangles with a row of shorts. (The dome will start curving inward)
  11. At each joint where four shorts come together, tape another short sticking straight up. Connect this short to the joints on either side with longs, forming new triangles.
  12. Connect the tops of these new triangles with a row of longs.
  13. Finally, add the last five shorts so that they meet at a single point in the center of the dome. (You might need to stand inside the dome to tape them together). To test your dome’ strength, see how many magazines you can load to top.

 

How strong was your dome? Did the results surprise you? Why or why not? What was the hardest part when you created your dome? How could you have made your dome stronger? Make a prediction, test it out, and then share your thoughts with other ZOOMers by sending them to our special feedback area.

Some of your Results:

 

Kacey, age 10 of Sunderland, MA wrote:
When I tryed the Geo Dome it was really hard. The directions weren’t that clear so it was really hard to make. When I tryed to see how strong it was it wouldn’t even hold one book!

Kanga, age 9 of S.A., TX wrote:
In my PROMISE class we built 3, 3 foot domes in 3 hours and even decoorated them!!!

Samantha, age 9 of NJ wrote:
Mine turned out really strong because I put a four-sided triangle under it and it supported my brother and my sister!

Sam, age 10 of Longmont, CO wrote:
Well I had a freind who helped me but he didnt read the instructions so the dome was not a big dome it was a 2 foot tall mini dome!

Andrea, age 9 of Bismark, ND wrote:
Making the triangles went pretty well, but when we started putting the triangles together… lets just say it didn’t go the way I expected.

Jael, age 8 of New York City, NY wrote:
It fell over so you need to make it strong.

Florencia & Ana, age 11 of Miami, FL wrote:
When I did the geodesic dome it was a little hard. It took like seven people to do it.

NEXT->Gumdrop Dome