Parkade Corrsion Issues 2

[dik]

Does anyone have historic information about when parkade corrosion became an issue. I recall in the 1970's that there was a court case in Toronto that was pretty definitive, but have since lost the information I had on this.

It's not for litigation reasons, but for part of a report of a RFP for a parkade restoration proposal.

Dik

 

[MiketheEngineer]

Try Google??

 

[ajk1]

I was an expert witness in court at Bell Canada vs O&Y. This investiagtion of a p.t. garage started in 1983 although it did not get into court until aabout 1991 as best as I can recall. So we were certainly aware in 1983 or 1984 and likely before that. The first technical committee of CSA S413 Parking Strcutures was started as best as I can recall in 1983. I was on that with Bickley as the chairman. I personally was aware of corrosion problems in garages in 1977 because that was when they started repairing the underground garage of the apartement building in which I lived at the time. I don't know the exact year when structural engineers became generally aware of it, but I would guess it to be around late 1970's to early 1980's. There was an ACI Journal with a feature article in it that might be considered the date of when structural engineers became generally aware of the issue. I will see if I can find that.

 

[SkiisAndBikes]

dik,

When I started working in the late 80's, the corrosion of parking structures was a well studied issue. In the attached reference by Litvan, it aludes that the problem was becoming widespread in the mid 1970's. Looking through an old report I have on the assessment and rehabilitation of bridge structures in Canada, they don't give any specific time period for when the corrosion problems started, however, they due state that there were a significant number of reinforced concrete bridges constructed during the 1950's. At this time, I don't think there was an understanding of the whole rebar, chloride, corrosion problems. Fast forward 10 to 15 years from time of initial construction of these older type bridge structures and you would be expecting to see problems become visible.

http://www.nrc-cnrc.gc.ca/obj/irc/doc/pubs/nrcc27897/nrcc27897.pdf

 

[Ron]

ajk1...my first thought was Bickley....but you beat me to it. I first became involved with John's old firm (Trow) in 1982 and he had been recognized as an expert in the subject quite a while before that.

dik...you might try to contact John Bickley inToronto...ajk1-got a phone number?

 

[SkiisAndBikes]

Ron, Trow is where I started in the late 80's. John Bickley had moved on by that point thus I did not get the opportunity to work directly with him.

I would guess Mr. Bickley is mostly retired now. There is a number available for him (not in Toronto), however I hesitate to post it on an open forum. The PEO website might have the contact info.

 

[dik]

Thanks ajk... that's the one I was thinking of and it was Olympia and York... I have a print of the transcript, somewhere...

I was working in Toronto in the mid 70's and by that time, parkade corrosion was a well established item. I met with John Bickley many times, but on other geotechnical issues...

We've been asked to put in a proposal for a parkade repair... and the terms do not include for a complete encapsulation of the existing and there has been no determination of the degree of carbonation... Chain drag and hammer to establish areas of repair. The RFP's are based on a couple of earlier engineering reports that are 'patching' the problem and have relegated the encapsulation (aka membrane replacement) to a minor 'afterthought'. This may not address the issue that the repair may only be a bandaid... and if the chloride intrusion is sufficient, it is essential that moisture be excluded...

The parkade was constructed in the mid 70's using f'c 3000 and 3/4" concrete cover, poor drainage, no hose bibs or maintenance manuals... my earliest parkades were undertaken at that time with 4500 psi, min and 1-1/4" to 1-1/2" conc cover... with drainage, bibs, and manuals (owners never followed this, but it was covered).

Dik

 

[Ron]

SkiisAndBikes....I was affiliated with Trow from 1983 to 1989. Probably have run in to you along the way.

 

[SkiisAndBikes]

Ron,

We possibly did cross paths, I was a summer student in 1989 on the bridge decks and then started full time upon graduation in 1990. Worked there until about 1994 before moving to Montreal.

 

[dik]

Anyone still do half-cell testing anymore? Most of the repair I've seen in the last decade has been to just hydroblast, patch and repair?

Dik