Why is a gap left between two sections of a bridge?

Expert Answers

An illustration of the letter 'A' in a speech bubbles

Basically all materials expand upon heating, whether we take the example of metals, water or other materials. This expansion is a function of the material properties (specifically the coefficient of thermal expansion), amount of heat supplied, degrees the temperature rises, etc. Thermal expansion takes place due to the increase in...

See
This Answer Now

Start your 48-hour free trial to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

Get 48 Hours Free Access

Basically all materials expand upon heating, whether we take the example of metals, water or other materials. This expansion is a function of the material properties (specifically the coefficient of thermal expansion), amount of heat supplied, degrees the temperature rises, etc. Thermal expansion takes place due to the increase in the kinetic energy of the constituent molecules as they are heated.

Thermal expansion is the reason we leave some gaps between sections of a bridge or two consecutive sections of railway tracks. With an increase in temperature (during daytime or during summer months), the bridge sections or the railway track sections will expand. With a drop in temperature (at night or during the winter), these sections will contract. If there was no gap between such sections, this regular expansion and contraction would cause stresses and enhanced wear and tear. In the case of bridges, this can also cause deflection of its sections.

Hope this helps. 

Approved by eNotes Editorial Team