Training 18: Limits and your responsibility

You are the engineer of record. ILX Calcs is a tool for a licensed engineer who already knows how to do the calculation and can judge the answer.

What the program does #

• It applies the code provisions as written, and it cites each one, so you can read it.
• Where a provision leaves a choice to the engineer (a deflection limit, a bracing assumption, a material), the choice is an input with its usual value prefilled, never a hidden assumption.
• It says what it does not know: Not feasible with the reason, (to confirm against the code text) on a clause not yet confirmed, a Preview label on the truss designers, and the verification status of each type.

What stays with you #

• The structural system and the load path. The program checks one member or element at a time, with what you tell it.
• The inputs. Soil values, site parameters, classifications, tributary areas, the end conditions you assumed. A correct calculation of the wrong input is wrong.
• Whatever a type leaves out. Every chapter has a Limitations section. Read it the first time you use a type. Connections, bearing, stability of the whole, constructability and field conditions are mostly not checked, unless a chapter says they are.
• The governing code. The app's editions are stated on each calculation (the header shows the main ones). Your jurisdiction may have adopted others, or amended them.
• Checking. Compare with a hand check or a second program, the more so for a type with weak verification (Training 17).
• Sealing. Nothing is sealed or approved by the program. Sheets carry the status line of your title block, Preliminary, not for construction until you change it.

A checklist before you issue #

1. Have I read the type's Limitations?
2. Are the governing checks the ones I expected? If not, why?
3. Did I read the failing and nearly failing rows, not only the status?
4. Is the input summary in the report what I meant? Self-weight, supports and units included.
5. Is any clause marked (to confirm against the code text), or any preview label on? Did I read those clauses?
6. How was this type verified, and does my case resemble those examples?
7. Would I sign this if the program had not been involved?

Help #

Use Support in the header for questions and problems about the program; include the calculation so we can see what you see. Write to services@ilxstudio.com for support, or to info@ilxstudio.com for anything else.