Why Bridges HAve Expansion Joints?

Question

Its is part of science

Answer 1

This is due to thermal expansion and contraction; railway tracks also have expansion joints.

In some countries the temperature can vary from freezing at night to very hot during the day, a temperature difference of around 40 degrees celsius.

Some metals have a high thermal expansion co-efficient and therefore expansion joints are used, otherwise there could be a tendency for a fixed joint to either be pulled apart by thermal contraction or buckled because of thermal expansion.

Hope this helps...

Answer 2

Expansion joints are used in bridges, buildings, and other structures to allow the structures to move without breaking. But why do they move? First, as the temperatures get hotter and colder, the structure materials expand and contract. Second, a vehicle is driven across the bridge, the expansion joints allow the bridge move with the vibration and motion created by the car. Third but not last, another important fact is wind. As the wind pushes and pulls on the structure, expansion joints allows movement, but strength for safety.

Answer 3

All materials expand when thy get hot, and contract when they get cold. In something like a bridge, a rigid structure would make it crack when it tried to expand. Putting in these expansion joints allows for the movement, so the bridge doesn't fall down on a hot day.

Answer 4

As u know, every material has a thermal expansion factor, so for almost all the materials, with the temperature increasing, we have an increase in length, surface and volume. Also the length of the rows and bars used in bridges increases with respect to temperature.
Engineers predict this phenomenon in designing level and leave free space for the rows and bars to expand. Else the steel used will be under an extra stress, that may lead to construction failure in critical conditions.

Answer 5

They need expansion joints because in the summer where it is hot the bridge will actually expand and in the cold it will contract. So if was just solid it would crack and be unsafe.

Answer 6

Due to increase and decrease in temparature , joint can expand and contract. If there is no expansion joint, bridges will fall down.

Answer 7

Yeah, it's physics. It allows for, uh, let me think, expansion..Out in CA, it also allows for the motion of earthquakes which we have a lot of and the bridge, buildings, etc, stay standing. Have a great day!!!

Answer 8

Joints prevent materials from becoming too stressed when they expand and contract due to changes in the temperature and humidity.

Answer 9

Thermal expansion during hot weather. The same reason railway tracks have gaps in them.