Materials: deck of playing cards, candy
Using the different methods above (leaning, bending, tearing) build a structure out of cards that can:
The “Science” of Card HousesEvery building is subjected to forces. Most forces acting on buildings are caused by:
Forces acting on the building need to be resisted by internal forces in the structure. To distribute the forces with playing cards a basic truss (series of triangles) is made. Triangles are extremely strong and distribute forces well. The joints of the triangles are vital to the stability of the structure. Bending and tearing the playing cards allows you to make stronger joints.
Wind can provide a torque (force that is not axial to the beam) on your building. To resist
this, members of the truss that are perpendicular to the two other members of the triangle are
added. Without this axial force, these additional members carry no load.
Compare the structures you created with the structure of an aqueduct. These ancient structures used arches rather than triangles to distribute the forces of the load. The Roman aqueduct below stretches 2950 feet long through Sierra de Guadarrama. It is made of rough-hewn massive granite blocks, joined without mortar or clamps.
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