A bridge is mainly comprised of girders, piers, towers, and perhaps cables. The girders are relatively horizontal, and the piers and towers are generally vertical. A bridge typically has two abutments, one at each end. These are all the elements to be dealt with.

A bridge is a structure built to span a physical obstacle, such as a body of water, valley, or road, without closing the way underneath. It is constructed for the purpose of providing passage over the obstacle, usually something that is otherwise difficult or impossible to cross.

Bridge failures can lead to injuries, loss of life, and property damage on a scale equal to plane crashes, terrorist attacks, and natural disasters. That’s why bridge designers, engineers, construction workers, managers, and inspectors take their jobs so seriously.

Bridges can be found in a variety of shapes, but 3 basic designs rule the day; beam, arch, and suspension.

Simply, Concrete, steel, and geometry. Their combination, their quality and their quantity, everything is crucial to make bridge strong. Bridges are often made using arches of concrete. Concrete has very high compression strength, and an arch is almost entirely under compression instead of tension.

All the conditions are above are for an ideal site of the bridge….

• Connected with roads:
• Strong embankment on both sides:
• Type of foundation:
• Requirement of material and labor:
• Flow of water:
• Straight stretch of river:
• Flow of river:
• Width of river:

A truss bridge is a befitting example of this type. A truss is a structure made of triangles which make it very strong to withstand heavy weights.

arch bridge

We had to build it using only use two materials: toothpicks and glue. That may sound hard at first, but its actually an incredibly fun and hands-on way to learn some practical engineering skills. If you don’t know where to start, you can find tips on how to make a sturdy bridge in this helpful video.

When you’re done putting together all the pieces yours should look like this. This particular bridge was able to hold the maximum 30 pounds.

If the diameter of the toothpick is 1/16″, then the radius is 1/32″ and the cross section area is 0.003 square inches. If the maximum strength is 50 Lbs, then the tensile strength is 16666 pounds per square inches (16666 Lbs/si).

Steps:

1. Place two marshmallows with the bases flat on your work surface.
2. Insert a toothpick into one of the base marshmallows of the first triangle at a 45-degree angle and another toothpick into the side of the top marshmallow.
3. Repeat the triangle making process from step 1 to create another matching trapezoidal shape.

Due to the materials used, many older truss bridges have had to be replaced around the world. Truss bridges are considered one of the most expensive to build bridges.

Originally, spaghetti was notably long, but shorter lengths gained in popularity during the latter half of the 20th century and now it is most commonly available in 25–30 cm (10–12 in) lengths. A variety of pasta dishes are based on it and it is frequently served with tomato sauce or meat or vegetables.

We quickly discovered that spaghetti is not very strong! It bends very easily, and breaks easily. I asked the boys if they thought multiple pieces of spaghetti could hold more weight, and possibly even hold up a book. We tried sticking about 20 pieces of spaghetti into the styrofoam disk.

12

10-ounce

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Q: Do Jet-Puffed Marshmallows contain Gelatin? A: Yes, the type of gelatin used in JET-PUFFED marshmallows is pork-based.