got stuck in equation

Forum|Forum|13 years ago
December 31, 2012
1 reply
4561 views

hi . . my name is usama khan
i am the student of civil engeering and we got assignment to make a project program on flexible pavement design using python.

i know very litle about programing. still learning from tutorials. u can call me a beginner.

now i need to solve this equation so that i can put this in python but the formula of design is very complex

Formula is :

log(W18) = (Z)(S)+9.36log(SN+1) -2.0+(log(dpsi/(4.5-1.5))(/(.40+1094/(SN+1)^2.5)+2.32log(Mr-)-8.07

every thing is constant except this SN. . i want to seperate SN like SN= rest of the stuff. how can i seprate it because manualy its impossible to take SN out.

so plz help me out.
log(w18)=Esals=50x10^6
Z=-1.645

S=0.45

dpsi=2.5

Mr=5800
these all are variables depending upon some factors. . but for ideal case we take these values. .
now i hope u got my question.
plz help

Civil_Engineering

Best answer by Werner_E

usama khan schrieb:
thanks for responding sir. .
did u iterate it ??
secondly i just want that SN= all other variables. .means how could get SN formula??
Regards

What you are asking for is a symbolical solution. As the variable SN is argument of log AND also exists outside in the term (SN+1)^2.5 you could not expect to get a closed solution. So the numerical approach shoen by Roger is the best Mathcad will be able to deliver. The steps necessary to find a numeric solution are done automatically by Mathcad. You may want to look for "solve block" in the built in help.

@Roger: I think Esals should be 50*10^6, not the logarithm of it