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Krautso (Civil/Environme)
18 Jul 02 11:54
I have a question regarding Performance Based Criteria for tendering the supply of Permanent Erosion Control Blanket. Currently my Department does not have a spec or approved product list for this material and I am wary of issuing a tender which a)narrows the field to one bidder or b) is so open that I dont necessarily get what I want.
I'm relatively new to this area and with the little bit of research Ive done, Im aware of the great variety of products out there. Has anyone tendered the supply of this material without using a) an approved product list or b) a tiered class system? If so I would be interested to hear which properties were used as criteria and what the results were.
p.s. I have no control over selection of the supplier beyond the criteria as it will be awarded to the low bidder.
cdh61 (Geotechnical)
26 Mar 04 16:19
字串6
Krautso,
If you are the one writting the tender you have a lot of control. You need to outline what you want the product to do and what is important so you get what you want. In the tender you could then start to specify specific properties, so if you want concrete block with opening, say so in tender, blocks must be etc... etc. This still leaves room for multi products, but at least you end up with what you want to use.
regards
layfieldman (Civil/Environme)
29 Mar 04 13:30
I would suggest looking at the ECTC (Erosion Control Technology Council) website or contacting someone from that organization. They have tables of what values permanent (as well as temporary) erosion control products should have. They consider velocity as well as permissible shear stress.
LHA (Civil/Environme)
30 Mar 04 7:26
字串7
I agree with you, Krautso, I stay away from Approved Product lists whenever possible.
I agree with layfieldman's approach and reference, but in addition to spec'ing parameters of what can be applied to the product, I would also spec lab tested performance parameters. With these, you can require the installing contractor to provide a bill of lading which verifies these lab specs are met...you can't readily field verify velocity and shear.
Require the Product to verify the following property, test method and results: Thickness, Resiliency, Mass Per Unit Area, Tensile Strength, Tensile Elongation, Tensile Strength @ 10% Elongation (typical value), Ground Cover Factor, Moisture Absorption, UV Resistance
Krautso (Civil/Environme)
28 Sep 04 18:01
WOW,
My hat is off to CDH1 and the rest of you for finally answering my question!! Two years, I was beginning to lose hope!! 字串7
The project is long over and was very successful. My department actually uses my E&S Control design as a model now.
The tendering was a pain, as I had to re-tender....twice. Eventually though, I got the product I needed and it performed as advertised.
Thanks all!
(Click:)
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