Negative Code Stress

As far as I can recall, this is the first time that I am getting a negative code stress.


This appears at Load case 10 and load case 12 (SUS -Seismic load).

1 (HYD) WW+HP
2 (OPE) W+T1+P1
3 (SUS) W+P1
4 (OPE) W+T1+P1+U1
5 (OPE) W+T1+P1+U2
6 (EXP) L6=L2-L3
7 (OCC) L7=L4-L2
8 (OCC) L8=L5-L2
9 (OCC) L9=L3+L7
10 (OCC) L10=L3-L7
11 (OCC) L11=L3+L8
12 (OCC) L12=L3-L8

Here are the results.

CODE STRESS CHECK PASSED: LOAD CASE 10 (OCC) L10=L3-L7

Highest Stresses: ( KPa )
CodeStress Ratio (%): 22.0 @Node 39
Code Stress: 38204.2 Allowable: 173295.2
Axial Stress: 12246.3 @Node 250
Bending Stress: 47927.0 @Node 39
Torsion Stress: 2749.5 @Node 110
Hoop Stress: 25006.9 @Node 170
3D Max Intensity: 26592.7 @Node 250

10 -450.6 204.8 1.000 1.000 9107.5 173295.2 5.3 B31.3
18 -533.3 -204.8 1.000 1.000 9051.8 173295.2 5.2 B31.3

18 -1051.6 204.8 2.392 1.994 8533.5 173295.2 4.9 B31.3
19 -6644.5 194.0 2.392 1.994 2766.1 173295.2 1.6 B31.3

19 -6644.5 -194.0 2.392 1.994 2766.1 173295.2 1.6 B31.3
20 -3883.6 380.5 2.392 1.994 5861.9 173295.2 3.4 B31.3

20 -1622.6 -380.5 1.000 1.000 8122.9 173295.2 4.7 B31.3
38 -18741.9 380.5 1.000 1.000 -8926.8 173295.2 999.0 B31.3 *

38 -44748.9 -380.5 2.392 1.994 -34933.8 173295.2 999.0 B31.3 *
39 -47927.0 1108.0 2.392 1.994 -38204.2 173295.2 999.0 B31.3 *

39 -47927.0 -1108.0 2.392 1.994 -38204.2 173295.2 999.0 B31.3 *
40 -44402.0 1285.0 2.392 1.994 -34394.5 173295.2 999.0 B31.3 *

40 -18533.1 -1285.0 1.000 1.000 -11431.7 173295.2 999.0 B31.3 *
60 -17080.2 1285.0 1.000 1.000 -9963.5 173295.2 999.0 B31.3 *

60 0.0 0.0 0.000 0.000 0.0 0.0 0.0 B31.3

Is this something that I am missing?

Thanks in advance.

Send the job in to Tech Support so they can look at it.

Thanks a lot

Email sent to caesarii@intergraph.com

-

Because you use a "lethal" combination of scalar summation and sign minus in your L10=L3-L7. Your L7 stress is from a construction load case (positive) and since is bigger than L3 stress (positive), hence the "negative" code stress.

Regards,