Trusses are
physically stronger than other ways
of arranging structural elements, because nearly every material can resist a much larger load in tension or compression than in shear, bending, torsion, or other kinds of force.
What makes a truss bridge strong?
Load-bearing capacity of truss bridges is huge due to the structure of interconnecting triangles
. The structure effectively manages both compression and tension by spreading the load from the roadway throughout its intricate structure.
What truss is the strongest?
In this experiment we have tested which type of truss bridge is the strongest, yet uses the least amount of material. Two of the most used truss bridges are of the
Pratt and Howe design
. Through our experiment it was found that the bridge design that minimized the maximum compression force was the Howe Bridge.
What forces must trusses withstand?
A truss is a structural system in which, due its construction and configuration, all members are subjected only to
pure tension or compression forces
.
What forces act on a truss bridge?
The forces acting on the this type of bridge are
compression, tension, torsion, resonace, and shear
. Compression takes place when the top chord of a bridge is being compressed. Some internal parts are also compressed, because parts of the truss bridge are being used to spread the weight out.
What is the weakest bridge?
We did further research after our experiment and learned that
beam bridges
are actually the weakest of all bridges and suspension bridges are the strongest.
What are the weaknesses of a truss bridge?
- Buckling. Buckling is an instability caused by the application of a force that leads to failure of the member. …
- Fatigue Cracking. Resonance sets up standing waves that travel back and forth through the truss causing horizontal members to flex up and down. …
- Seismic Forces. …
- Torsion.
What are the 3 types of trusses?
- King Post truss. A king post truss is typically used for short spans. …
- Queen Post truss. A queen post truss is typically a vertical upright with two triangles either side. …
- Fink truss. …
- Double Pitch Profile truss. …
- Mono Pitch Truss. …
- Scissor Truss (also known as Vaulted Truss) …
- Raised Tie Truss.
How much weight can a truss hold?
According to the IRC, the minimum live load capacity of a roof truss for non-sleeping areas should be around
40 pounds per square foot
. Again, if it’s built for sleeping areas, it should be around 30 pounds per square foot.
Which is better Pratt or Howe Truss?
The Pratt truss disspipated the load more efficiently than
the Howe truss, although both truss bridges dissipated the force significatnly more effectively than the beam bridge. In addition, the Pratt truss deflected the least and held the most, on average, while the beam bridge deflected the most and held the least.
Where do trusses commonly fail?
When a truss collapses, it is usually because of the failure of either
the top chord (in compression, unless a cantilever)
or the bottom chord (in tension, unless a cantilever). If a truss buckles or overturns, it is usually because of the failure of an adjacent truss or its bracing.
What is a truss pattern?
The truss pattern refers to
the arrangement of internal vertical and diagonal members
. The top and bottom horizontal members are often referred to as truss chords or booms.
What is a truss that you wear?
A hernia truss or belt is
a supportive undergarment for men designed to keep the protruding tissue in place and relieve discomfort
. If you have an inguinal hernia, a hernia truss can help you feel more comfortable temporarily, but it doesn’t treat the hernia. Talk to your doctor if you want to use a truss.
What are the 5 types of truss bridges?
- Pratt. The Pratt truss bridge utilizes diagonal and vertical beams. …
- Howe. The Howe truss bridge is similar to the Pratt design with only a few differences. …
- K Truss. The K truss bridge literally makes a backward ‘K” shape along the structure of the bridge. …
- Bailey. …
- Warren. …
- Bowstring.
What are the major components of a truss bridge?
Each truss is composed of
a top chord, a bottom chord, and several verticals and diagonals
. The two trusses are connected together by a series of transverse members—struts, lateral bracing, and floor beams. In early truss bridges, all of these members would have been made of wood or iron.
What are the pros and cons of a truss bridge?
- Truss bridges can span virtually any distance. …
- It offers a superior level of strength. …
- The road is placed on top of the span. …
- They are an affordable bridge design option. …
- Truss bridges are highly adaptable. …
- There are multiple material options available.
