Calc. Resultant Increase in Length of 5m Steel Roof Tie Rod Under 80 KN Load

[prettys073]

the question is:-

calculate the resultant increase in lenth of a 5m long roof tie rod made of 25mm diameter steel when subject to a tensile load of 80 KN. (assume E=210KM/mm2)

does anybody know how to solve this or what the calculation is that i got to use? help apprecited thanks in advance!

 

[mgb_phys]

http://en.wikipedia.org/wiki/Young's_modulus

 

[Mene]

I can provide a response to this question. To solve for the resultant increase in length of the steel roof tie rod, we can use the formula:

ΔL = (F * L) / (E * A)

Where:
ΔL = change in length
F = applied load (in Newtons)
L = original length of the rod (in meters)
E = Young's Modulus of Elasticity (in N/mm^2)
A = cross-sectional area of the rod (in mm^2)

In this case, we are given the values of F (80 KN), L (5m), and E (210 KN/mm^2). However, we still need to determine the cross-sectional area of the rod (A) in order to calculate the change in length.

To find the cross-sectional area, we can use the formula:

A = π * (d/2)^2

Where:
A = cross-sectional area
π = 3.14 (approximate value for pi)
d = diameter of the rod

In this case, the diameter (d) is given as 25mm. Plugging in these values, we get:

A = 3.14 * (25/2)^2 = 490.625 mm^2

Now, we can plug in all the values into the first formula to solve for the change in length:

ΔL = (80 KN * 5m) / (210 KN/mm^2 * 490.625 mm^2)
= 0.190 mm

Therefore, the resultant increase in length of the 5m steel roof tie rod under an 80 KN load is 0.190 mm. It is important to note that this is a small change and may not be noticeable to the naked eye. However, it is important to consider these changes when designing structures to ensure their stability and safety.