Standards for Geotechnical investigation work 4

[wiele]

How do I specify the scope of work for preliminary Geotechnical investation work for a long overland conveyor project?

 

[BigH]

My initial thoughts:

I realize that there may be a tendancy of trying to specify a specific program for geotechnical investigation - actually, I have always hated getting these things from prospective clients UNLESS he was well versed in what he wanted.

My suggestion is to sit down and write out a detailed description of the project - from where to where? - type of structure - individual footings for conveyor support or long parallel grade beams --- type of loading to be had --- quirks in performance (how settlement sensitive, etc. ---- nature of structure ----- etc. THEN, get two or three reputable geotechnical firms to submit their program on investgation. Look at their proposals, pick the one that appears to be the most positive, call him in and discuss/negotiate with him any revisions, price, etc. Geotechs usually know the nature of the programs required for study better than the clients - at least from the point of view of providing the necessary information that the client's designers will need to put out tender drawings and specifications.

I am sure our good mates will add to this.

Best regards.

 

[Focht3]

No need to comment - BigH gave excellent advice.

(Would you tell your doctor how to use his stethoscope?)

 

[BigH]

Focht3: In China where a reported 55% of the rural doctors have never graduated from high school - perhaps!! - given that the language problem could be overcome!! [fumanchu]

 

[yangjia]

BigH, Do you guys have any projects in China?

 

[tylermacleod]

Some very good advice from BigH. I have a little ramble about a recent experience that may or may not be helpful. I will put it out because it was for a related type of project. I recently met a client about a similar project on a very poor site. The settlement tolerance became key. A large pile of aggregate was to be placed next to the conveyors. The loading from the aggregate was going to induce lateral movement of the conveyor supports. The original conveyor design was changed to allow the system to function with the supports misaligned by as much as three to four inches. This helped reduce the amount of site improvements that were required.

Regards.

 

[BigH]

tylermacleod:
No ramble is a ramble in these threads which points out case histories (the best to learn from is what experiences others have had)! You keep on rambling - ramblingman!!

Best to all!

 

[coneboy]

In addition to the Geotech concerns which BigH mentioned you might also want to take into consideration if any of the consultants have soil investigation experience in the project area. This would enable the choosen consultant to use the best type of drill rig for the expected ground conditions.

For example: If one of the consultants had thought the project area is primarily underlain by gravels, cobbles and boulders then Becker Hammer testing might provide a more cost effective site investigation than auger drilling/SPT testing.

Best of luck
Coneboy

 

[BigH]

I agree with Coneboy - use local guys (which I sort of thought would be understood). One reason that I used to scour our companies reports was to see where they worked. On one site, for a feasibility level study (not even drilling) for co-gen plant, I was able (in Norhern Ontario) to find (1) a company soils report for one of the specific sites under consideration (2) a soils report immediately adjacent to a site under consideration and (3) an Ontario Hydro report for the third site. In essence, good geotechs will be history buffs, in my humble view! Our company's archives helped many a time.