Importance of Modulus of elasticity in Construction:
It is highly crucial to define modulus of
elasticity of concrete in the design of concrete structure. Linear analysis of
elements, which is based on the theory of elasticity, is used to satisfy
requirements of both ultimate and serviceability limit state for instance in
the case of pre-stressed concrete that demonstrate un-cracked section up to the
failure. In addition to compute deflections which are required to be limited
under the serviceability requirements in all structures. Finally, knowledge of
the modulus of elasticity of high strength concrete is very important in
avoiding excessive deformation providing satisfactory serviceability and
avoiding the most cost-effective designs.
Why I-shaped beams are used in
Railway tracks?
Generally rail tracks are made in 'I' Section. We might wonder
many times that why any other shape is not used, We might also wonder, why
solid section is not used? Well here is the answer. Upper half of the track should be wide enough to support the wheel
and lower half should be wide & thick enough for clamping. Taking out extra
materials saves significant amount of iron without compromising over strength
thus giving it the shape of 'I'. Rail needs to be stiff in the vertical
direction to take the load of the train. It needs to be relatively flexible in
the horizontal direction so it can easily bend around curves. So material is
reduced at the center to allow a bit of flexibility. The below diagram shows the cross section of the modern rail
track.
Comments