Reading up on the failure of the Sleipner A drilling platform, much of the blame is not-so-subtley placed on the unconservativeness of the ACI 318-95 shear provisions - specifically, the ones that provide shear capacity for members under compression.
These provisions (eq. 11-6 in every...
Lately I find myself having to put together signed and sealed letters stating that some construction condition as-built is acceptable.
I'm never quite sure exactly how thorough these need to be. I find myself endlessly adding verbiage to try to cover myself from certifying something beyond the...
As part of a lifting insert, we have some #4 rebar with the following dimensions (see attached). This is a bar that has been used successfully elsewhere, but our rebar supplier is balking at it with claims of "overstressing the rebar".
Is there any guideline for minimum distances when multiple...
I'm currently working on the design for the cast in place bulkhead on top of a steel sheet pile. To resist the rather significant lateral loads, battered precast piles are being placed every 5 ft. I'm trying to check the design with a STM, essentially treating it as a sort of vertical concrete...
I'm in the process of designing some circular concrete tanks for a wastewater treatment plant. The tanks have separately cast concrete roofs with pin connections at the walls. I've designed several WWTP in the past, but this is our firm's first tank with a roof, so we're using a few existing...
I'm currently designing some concrete tanks for a wastewater treatment plant. Previously to calculate the seismic loads, I used the method from ACI 350.3, with the substitutions from ASCE 7-05 chapter 15, section 15.7.7.3.
I'm currently looking at the same chapter and section in ASCE 7-10, and...
We're in the final stages of submittal for a wastewater treatment plant. The tank on the plant was large enough (around 200' x 100') that adding an expansion joint seemed prudent. Our detail for the expansion joint is attached, as this is our first time designing a tank this size, I'd love some...
More info here: http://abcnews.go.com/US/wireStory/part-texas-equestrian-center-collapses-19464194#.UcXugCt24fI
Looks like it was under construction.
Brian C Potter, PE
http://simplesupports.wordpress.com
We've been tasked with evaluating the structure of an aging residential dock made of precast concrete, sitting on precast concrete piles. The structure is around 50 years old, and has experienced extreme corrosion damage (see attached pics). We suspect it was built with surplus precast that had...
Thought it'd be useful to collate a list of structural engineering web resources. Mine are listed below, feel free to suggest more.
Building Codes
Archive.org Public Safety Codes: Collection of various building codes available for download. Particularly useful is every version of the IBC –...
Near Mt. Vernon: http://abclocal.go.com/ktrk/story?section=news/national_world&id=9113940
No real info yet.
Brian C Potter, PE
http://simplesupports.wordpress.com
So I noticed, despite being largely ignored in favor of the IBC, the NFPA 5000 code has continued to be revised and updated every three years: http://www.nfpa.org/AboutTheCodes/AboutTheCodes.asp?docnum=5000&tab=docinfo
Does anyone know of any jurisdictions that actually use the NFPA 5000? A...
I'm reviewing a precast calculation package, and part of the analysis relies on this equation to check a column's capacity:
(phi)*Pn = 0.55*f'c*(phi)c*Ag[1 - (k*l/(32*d))^2]
It seems to be some sort of strange, normalized Euler buckling equation. It seems somehow familiar to me, but I've been...
The paper "Steel Reinforcing Bar Specifications in Old Structures" (link: http://www.concrete.org/PUBS/JOURNALS/AbstractDetails.asp?ID=236) refers to a recommendation by the Department of Commerce for standard rebar sizes - does anyone know what this recommendation was (title, etc)? I assume it...
I'm looking for information on when HSS section members first began to be produced and used. The only information I have is that they first appear in the AISC design manual in LRFD 2nd Edition, but presumably they must have been in use prior to that. Can anyone shed some light?
Brian C Potter...
