THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
(OP)
The majority of engineering that I perform is done through ASD. Part or all of this practice may be changing in the future.
I notice that in some published, post-installed, Technical Guides or Design Manuals, spacing requirements are not available for Allowable Load charts that employ ASD. When I inquired of this with a post-installed anchor representative, over the phone, I was told, in that person’s opinion, that their company is leaning toward focusing more so on SD, Strength Design, rather that ASD, Allowable Stress Design. In fact, I was then directed to that company’s Post-Installed Anchor Software, which is exclusively designed by the employment of SD, Strength Design. ASD is not even a consideration for their, as well as their competitor's software.
In your opinions, if any of you have experienced this and/or have any insight or foresight regarding this, is this sway toward SD and away from ASD applicable only within the scope of post-installed anchors? Or, is this, perhaps, an indication of a likely future trend for engineering as a whole?
To help understand the current state, when commenting, please weigh in, if you will - Are you ASD or SD? (I realize the results of this poll will be solely influenced only by the number of participants.)
In your opinion, is there a benefit or detriment to ASD or SD, only regarding post-installed anchors. In general, I believe the ASD vs SD debate requires a separate post.
Thank you all!
I notice that in some published, post-installed, Technical Guides or Design Manuals, spacing requirements are not available for Allowable Load charts that employ ASD. When I inquired of this with a post-installed anchor representative, over the phone, I was told, in that person’s opinion, that their company is leaning toward focusing more so on SD, Strength Design, rather that ASD, Allowable Stress Design. In fact, I was then directed to that company’s Post-Installed Anchor Software, which is exclusively designed by the employment of SD, Strength Design. ASD is not even a consideration for their, as well as their competitor's software.
In your opinions, if any of you have experienced this and/or have any insight or foresight regarding this, is this sway toward SD and away from ASD applicable only within the scope of post-installed anchors? Or, is this, perhaps, an indication of a likely future trend for engineering as a whole?
To help understand the current state, when commenting, please weigh in, if you will - Are you ASD or SD? (I realize the results of this poll will be solely influenced only by the number of participants.)
In your opinion, is there a benefit or detriment to ASD or SD, only regarding post-installed anchors. In general, I believe the ASD vs SD debate requires a separate post.
Thank you all!






RE: THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
RE: THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
RE: THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/
RE: THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
Are you a Florida engineer? Are you accustomed to using anchor NOAs or just using manufacturers data that is provided in ASD?
I've had several meetings with technical representatives for Powers/Stanley B&D, Hilti and Simpson... All of which are concerned that east coast states and a couple in between are still doing ASD post installed anchors.
I've spoke to certain building officials about this and there are some who have absolutely no opinion either way. I think it has a lot to do with where you live or practice.
RE: THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
RE: THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
"It is imperative Cunth doesn't get his hands on those codes."
RE: THE FUTURE OF POST-INSTALLED ANCHORS – ASD vs SD
Step 1) come up with an ultimate capacity somehow. Testing matching your situation exactly trumps all of course. In the absence of such glorious similitude, an evaluation method calibrated to testing is the way to go. Nowadays, the CCD method and its derivatives (app D) are, without question, the latest and greatest.
Step 2) use some statistically suitable scheme to convert ultimate capacity into a design value. This can be SD, LRFD, ASD, or Jupitorian stress transformation.
I expect that LRFD will eventually supplant ASD in all materials including wood, soil, and concrete anchorage. This will happen for the same reason that it's happened in concrete and steel design: it's inherently more rational. Load variability and capacity variability are independent stochastic mechanisms. You simply can't achieve uniform levels of structural reliability if those mechanisms aren't treated separately. And uniform structural reliability is always our goal even though we rarely express it explicitly in our day to day work.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.