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Types of mechanical forces

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A force exerted on a body can cause a change in either the shape or the motion of the body.The unit of force in SI system is the Newton(N) and CGS system is dyne.No solid body is perfectly rigid and when force are applied to it,changes in dimension occur.such changes are not always perceptible to the human eye since they are negligible. For the example,The span of a bridge will sag under the weight of a vehicle and a spanner will bend slightly when tightening a nut. It is also important for civil engineers and designers to appreciate the effects of forces on materials.Together with their mechanical properties of the materials. There three main types of mechanical forces that can act on a body.They are 1)Tensile force 2) compressive force and 3) shear force
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What are the types of beams??

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Classification of beams based on supports
  1. Simply supported - a beam supported on the ends which are free to rotate and have no moment resistance.
  2. Fixed - a beam supported on both ends and restrained from rotation.
  3. Over hanging - a simple beam extending beyond its support on one end.
  4. Double overhanging - a simple beam with both ends extending beyond its supports on both ends.
  5. Continuous - a beam extending over more than two supports.
  6. Cantilever - a projecting beam fixed only at one end.
  7. Trussed - a beam strengthened by adding a cable or rod to form a truss.
Based on geometry:
  1. Straight beam – Beam with straight profile
  2. Curved beam – Beam with curved profile
  3. Tapered beam – Beam with tapered cross section
  4. Based on the shape of cross section:
    1. I-beam – Beam with ‘I’ cross section
    2. T-beam – Beam with ‘T’ cross section
    3. C-beam – Beam with ‘C’ cross section
Based on equilibrium conditions:
  1. Statically determinate beam – For a statically determinate beam, equilibrium conditions alone can be used to solve reactions.
  2. Statically indeterminate beam – For a statically indeterminate beam,  equilibrium conditions are not enough to solve reactions. Additional  deflections are needed to solve reactions.

Classification of beams based on materials:

1. Timber Beam

2. Steel Beam:

3. Concrete beam:


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