GUIDELINES FOR THE PREPARATION OF A GEOTECHNICAL REPORT
GEOTECHNICAL REPORT
All the following properties, for each soil layer encountered, should be determined by field or laboratory testing and summarized in the geotechnical report:
1. Soil classification and elevations
2. Standard penetration values
3. Unconfined compression strength.
4. "In-Situ" soil density and moisture content
5. Other properties unique to site conditions
The following items should be discussed in the geotechnical report.
1. Geologic description of site
2. Observed and expected ground water conditions
3. Expected frost penetration depth
4. Corrosion potential of soil and corrosion protection recommendations
5. Site access and potential construction difficulties
6. Dewatering or site drainage requirements
7. Backfill material recommendations
8. Settlement considerations
9. Additional information to aid foundation designer
10. Recommended types of foundations
11. Design parameters for uplift, download and lateral load
12. Factor of safety considered when allowable vs. ultimate design parameters are provided
13. Recommended construction techniques and inspections.
GUIDELINES FOR THE PREPARATION OF A GEOTECHNICAL REPORT
Reactions shown for all structures are for maximum wind loading conditions based on an allowable working stress design. Reactions have not been reduced by a factor to account for increased allowable stresses due to wind loading.
SELF-SUPPORTING TOWERS
Tower Face Width
Compression / Leg
Tension / Leg Shear/Leg Overturning Moment / Tower
Feet kips kips kips foot-kips
GUYED TOWERS
Base Reaction
Anchor Number Radius (feet) kips (Compression) kips (Shear) Horizontal Vertical Uplift Force (kips)
1-3 4-6 7-9 NOTE: Anchor radius are to be measured from the center of the tower
MONOPOLES
Pole Base Diameter _____________Inches
Overturning Moment _____________foot-kips
Shear
Compression inches foot-kips kips
FOUNDATION TYPES
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Pier and Pad Straight Shaft Drilled Piers Mat Foundations Drill and Bell Foundations Driven Piles Rock Anchors Buried Anchor Blocks (Deadmen) for Guy Anchors |
These guidelines cannot be copied, reproduced or otherwise used, in whole or Page in part, beyond their intended purpose, without the express written consent of USEDTOWERS.COM.
PURPOSE AND INTENT: The intended purpose of these guidelines is to assist the Customer and/or Owner retains the services of a Geotechnical Engineer.
It is not USEDTOWERS.COM's purpose or intent to supersede the Geotechnical Engineer's knowledge, judgment and/or experience. It is the Geotechnical Engineer's responsibility to add or delete from these items, based on local site conditions and other factors.
Recommended construction techniques and inspections
DISCLAIMER: USEDTOWERS.COM will not accept any liability, either expressed or implied, for the use of, or omissions in, these guidelines. These guidelines are considered as proprietary data and the sole property of USEDTOWERS.COM.
EXPLORATORY BORINGS: Borings should be taken at tower legs for self-supporting towers and at the base and anchor points for guyed towers. For small self-supporting towers, two borings may suffice. For large self-supporting towers one boring should be taken at each tower leg. A "small" self-supporting tower is assumed to have a face width less than 20 feet and a compression load less than 50 kips per leg. For pole structures, one boring may suffice.
The minimum boring depth should be 30 feet for pole structures, self-supporting towers and guyed tower bases. For guyed tower anchors, the minimum depth should be 15 feet. The actual depth of boring must be determined by the Geotechnical Engineer based on reactions, soil conditions and the type of foundation recommended.
If borings cannot be advanced to the desired depth, rock borings should be taken. Rock Quality Designation (ROD) values and compressive strengths should be determined.