Williot diagram

[MotorCity]

Can someone please point me to a reference or example that describes how to use and construct a Williot or Williot Mohr diagram? I believe it is an osolete graphical method to determine the forces on truss members.

I came across a sketch of such a diagram on a set of wood truss drawings from the 1940's. It seems like a fairly simple method, I just can't seem to decode how it works. Any insight or hints would be great.

 

[rb1957]

try goggling it ! geeze i don't like it when people don't do basic research, and yes, i am a grumpy olde fart

 

[rb1957]

ok, having gone over the hits, i've give you that one (though it wasn't clear that you had tried this avenue).
most of the hits were useless "stubs", the most promising was a text that'd cost about $40.

i might look up some of my olde books tonight (but there again, i might forget).

 

[MiketheEngineer]

Did it many times many years ago. Some older strucutral books still have samples. Sorry - I don't remember how...

 

[dhengr]

MotorCity:
Take a look at any good text book for the Analysis of Statically Indeterminate Structures, pre 1970's, when the computer still wasn’t doing all our analysis for us. For example:
1.) “Statically Indeterminate Structures,” by Paul Andersen, Ronald Press Co.
2.) “Analysis of Statically Indeterminate Structures,” by J.I. Parcel & R.B.B. Moorman, Wiley & Sons.
3.) “Theory of Structures,” by S.P. Timoshenko & D.H. Young, McGraw-Hill Book Co.
And many others.

 

[jmcoope3]

None of you had professors that made you do Mohrs Circles? For shame.

This doesn't mean I remember how to begin to make one... I just remember hating them.

 

[Denial]

My VERY VAGUE recollection is that for truss FORCES you use a MAXWELL diagram, whereas for truss DEFLECTIONS you use a WILLIOT diagram. (I was taught the former, eons ago, but not the latter.) This nomenclature correction might enable you to aim your Google weapon a bit more accurately.

Even more vaguely, I think that the Maxwell diagram is only applicable to determinate trusses. In effect it is a conjoining of the force polygons for each joint, in such a way that the force in each member appears only once in the overall diagram. The force vectors on the Maxwell diagram are parallel to their members, and of a length proportional to the force magnitude.

I have just de-dusted my yellowing copy of "Theory of Structures" by Timoshenko & Young. Cough. Cough. The notation system generally used in constructing a Maxwell diagram is "Bow's notation" (another arrow for your Google quiver). There is a good explanation of both the diagram and the notation in its Article 2.4.

 

[jmcoope3]

Just found an electronic copy of a text with a Williot Mohr diagram in it (found on books.google.com "Graphical Methods in Structural Analysis" by D.S. Prakash)... not a Mohrs circle, shame on me for being mechanical.

From my reading i'd like to suggest getting Etabs or Risa.