Bridge Design and Construction

1
Bridge Design and Construction

• The steps to designing and building the strongest
  but lightest bridge

2
The bridge kit

• The UTA kit consists of 3 sizes of balsa wood
• Elmers All purpose Glue
• Toothpicks

Small
Medium
Large
3
Maximum Length of Bridge 18 inches
No higher than this line
7 in.
14 inches
4
Research the Major Bridge Truss Designs at
http//www.matsuo-bridge.co.jp/english/bridges/ind
ex.shtm

• Howe
• Pratt
• Warren 1
• Warren 2

5
Pitsco Bridge Tester

• The Pitsco Bridge tester uses hydraulics to move
  a board that is placed on the decking. A center
  section through the middle of the base of the
  bridge must be left open for testing.

6
The Pitsco Bridge Tester

• The part of the tester that supports the bridge
  is called the abutments. The end width of the
  bridge must be narrow enough for the bridge to
  rest securely on the abutments.

Abutment
7
Pitfalls to Avoid

• The decking cannot be thicker than the width of
  the largest board plus the width of the smallest
  board.
• When viewing the bridge from the end, an open
  area 75mm by 50 mm should be visible.

Bridge Decking
8
Inside Dimensions of Roadway

• There is a minimum inside dimension that is the
  innermost wood on the bridge decking. The
  minimum inside width is 7.5 cm and maximum
  outside width is 14.0 cm.

5.0
7.5
Inside dimensions