HP 50G, Руководство пользователя

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information tell us is that somewhere between
φ
= 58
o
and
φ
= 59
o
, the shear
stress,
τ
’
xy
, becomes zero.
To find the actual value of
φ
n, press
$
. Then type the list corresponding to
the values {
σ
x
σ
y
τ
xy}, for this case, it will be
{ 25 75 50 } [ENTER]
Then, press
@CC&r
. The last result in the output, 58.2825255885
o
, is the actual
value of
φ
n.
A program to calculate principal stresses
The procedure followed above to calculate
φ
n, can be programmed as follows:
Program PRNST:
« Start program PRNST (PRiNcipal STresses)
INDAT Enter data as in program MOHRCIRC
CC&r Calculate
σ
c, r, and fn, as in MOHRCIRC
“
φ
n” TAG Tag angle for principal stresses
3 ROLLD Move tagged angle to level 3
R C DUP Convert
σ
c and r to (
σ
c, r), duplicate
C R + “
σ
Px” TAG Calculate principal stress
σ
Px, tag it
SWAP C R - “
σ
Py” TAG Swap,calculate stress
σ
Py, tag it.
» End program PRNST
To run the program use:
J
@PRNST
Start program PRNST
25˜
Enter
σ
x = 25
75˜
Enter
σ
y = 75
50`
Enter
τ
xy = 50, and finish data entry.
The result is:
Ordering the variables in the sub-directory
Running the program MOHRCIRCL for the first time produced a couple of new
variables, PPAR and EQ. These are the Plot PARameter and EQuation variables