NCMA E-TEK 17.1D - Lintel Design 1

[Jerehmy]

Table 4 in the tek has allowable moments for lintels. I tried verifying the designs but am getting significantly smaller allowable moments for 8" lintels than those posted in the tek and can't seem to trace the error. Has anyone else successfully verified these capacities?

I have attached a mathcad screen shot and an excel screenshot. I changed certain variables in excel to try and find the issue. I can't seem to pinpoint my error, any help would be appreciated.

https://www.dropbox.com/s/sah33t1aha2ybzy/excel 1.PNG?dl=0

https://www.dropbox.com/s/csoq21xho3mlwoq/mcad 1.PNG?dl=0

 

[dik]

Rather than use dropbox, can you just use the eng-tips file loader?

Thanks, Dik

 

[Jerehmy]

Sure, was just having trouble attached both to one post.

http://files.engineering.com/getfil...3-51f6-417c-bd76-ccd396769143&file=mcad_1.PNG

http://files.engineering.com/getfil...-59c9-46f1-afb4-b76123e302c6&file=excel_1.PNG

 

[wannabeSE]

Check your calculation for rho. It looks like the whole depth of the block, 7.625", is used instead of the depth of reinforcing d=4.375"

 

[Jerehmy]

Ah yes, thank you. What a silly error, I looked at it longer than I care to admit. Thanks again

 

[concretemasonry]

The people that write and contribute to the NCMA TEKs are in large part, the same as many of those that create the ACI/TMS 530 standards that are adopted by most model codes and standards. - ACI just has the publication and distribution abilities that the other organizations did not want to get involved in.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[dik]

and quickly on my TI-NspireCX CAS I get the following (not checked) and variables can have subscripts and superscripts...

Part of a thread in Engineering Programs/Apps

Dik