Understand Stress, frame, and beam. Bow's Notation


Very often, one has to do some construction himself. (Building a door for a fence, building a house, a shed, a shelf, a tree house for his kids ....) If he is ignorant of the methods to compute stresses, he would be unsure of how thick the material should be.
Hence knowledge in stress calculation is necessary for a man's up-building.

Moreover, the method is NOT difficult at all.

In the following few sheets, I am going to explain Bow's method in finding stresses.
Even if you are not going to learn Bow's method, and you already know the triangle of forces in statics, reading the first few sheets would already enable you to do the calculations.


  1. Sheet 1
  2. Sheet 2
  3. Sheet 3
  4. Sheet 4
  5. Sheet 5

The following concerns with "BEAM", etc.

  1. Sheet 6
  2. Sheet 7
  3. Sheet 8
  4. Sheet 9
  5. Sheet 10
  6. Sheet 11
  7. Sheet 12
  8. Sheet 13
  9. Sheet 14

The following are the programs, test data, test result for the program described in sheet 11
Do not try to understand the working of the program. It is MUCH FASTER to write your own program than try to figure out the logic of a program. They are given here so that you may pick up some useful programming habits and skills.

  1. An interactive Qbasic program to prepare data
  2. The output from the above program
  3. The beam program
  4. The output from the beam program

If, after reading these sheets, you feel interested in structural mechanics, I would recommend you the books by S. P. Timoshenko

  1. Strength of Material, Part I and II.

    The followings require deeper knowledge of Mathematics.

  2. Theory of Elasticity
  3. Theory of Plates and Shells
  4. Theory of Elastic Stability
S. P. Timoshenko is one the the persons I highly respect, and he wrote books full of insight.
Also, the book by G. H. Ryder "Strength of Materials", is also very readable.

If LORD will continue to use me, I will write about Finite Element Method in stress analysis, in the future. In the meantime, I hope you will read Serge Lang's book "Linear Algebra", because linear algebra (matrix, eigenvalue problem, symmetric matrix, ...) would enable us to comprehend the numerical methods used in Finite Element, and Serge Lang wrote really execellent books.
Moreover, in Serge Lang's book, he explained the decomposition of a matrix into Jordan Canonical form, and this is immensely important, if one is to understand System of Ordinary Differential Equations with constant coefficients (as well as system of DIFFERENCE equation ,not differential equations). And with it, will open the way to understand "dynamical systems", the way that many things develop with time.

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