Module 05
Cables
Structures that carry load in pure tension, and why their shape depends on how the load is applied.
What this module covers
- Explain why a cable can only carry tension, and what that means for its shape
- Show that the horizontal component of tension is constant along a cable
- Analyse a cable carrying concentrated loads
- Derive the parabolic cable profile and the relationship between sag, span and thrust
- Distinguish the parabola from the catenary and know when each applies
Lessons
Why the horizontal pull is constant, and how to analyse a loaded cable.
Start lesson →Deriving the cable shape under a uniform load, and when the catenary matters.
Start lesson →
Module checkpoint
Check what you have taken in
3 questions
Question 1
A cable spans 50.0 m between level supports carrying 6.0 kN/m along the span, with a sag of 5.0 m. What is the horizontal thrust in kN?
Question 2
Where is the tension in a cable smallest?
Question 3
A cable's sag is halved while the span and load stay the same. What happens to the horizontal thrust?