the

Why Are Triangles Stronger Than Squares?

SO A STADIUM BEARS LOADS JUST LIKE A REGULAR BUILDING,

BUT UNLIKE A REGULAR BUILDING,

YOU CAN'T HAVE A LOT OF BEAMS TO SUPPORT THE ROOF IN THE MIDDLE,

BECAUSE THAT WOULD OBSTRUCT THE VIEW,

WHICH IS THE WHOLE REASON YOU GO TO A STADIUM.

OTHER THAN THE HOT DOGS.

YOU HAVE TO DESIGN SUCH THAT YOU KNOW WHERE THE FORCES ARE GOING

AND HOW TO DIRECT THEM.

THE UNIVERSITY OF PHOENIX STADIUM

ACTUALLY EMPLOYS BRUNEL TRUSSES.

THIS IS A KIND OF STRUCTURE

THAT REALLY SUPPORTS THE STADIUM'S ROOF

USING AN ARCH THAT'S FORMED OF A LOT OF TRIANGLES

TO BEAR THE LOAD.

Narrator: LET'S EXAMINE THE STRENGTH OF TRIANGLES.

RECTANGLES, WHEN SUBJECTED TO FORCE,

EASILY COLLAPSE INTO RHOMBUSES.

BUT A TRIANGLE DISTRIBUTES FORCE DOWN ITS SIDES

AND MAINTAINS ITS SHAPE.

Man: SO TAKE THIS TRIANGLE

AND START TILTING IT AND TRACE WHERE THE TIP IS,

AND WHAT SHAPE DOES IT MAKE?

AND ARCH.

SO, THE STRONGEST POINT OF AN ARCH

IS ALMOST EVERY POINT ALONG ITS CURVE,

AND IF YOU WANT TO SUPPORT THAT, JUST ADD MORE TRIANGLES.

Narrator: YOUR TRUSSES WILL BE MADE OF SOLID STEEL.

EACH WILL MEASURE 700 FEET LONG, 87 FEET HIGH,

AND 17 FEET WIDE,

AND WEIGH 3.6 MILLION POUNDS.

I CAN'T EVEN FATHOM THAT IS.

EVERYTHING IS MEASURED, TO ME, IN DONUTS,

SO THAT'S A LOT OF DONUTS.

[ DING! ]