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TOWER DESIGN AND CONSTRUCTION
CHAPTER 2: SITE DESIGN AND DEVELOPMENT
TABLE 2-2 COMPARISON OF TOWER TYPES
Factor
Self-Supporting
Cost
Guyed
Monopole
High
Moderate
More material required
More assembly cost required
Foundation more expensive
Land costs may be higher
because more area is required
for guy wires.
High
Moderate
Self-supporting structure is
typically more stable and better
able to resist wind loading.
Provide resistance to wind
sway, but are susceptible to
torquing, especially when dish
antennas are installed.
Land Required
Low
High - Location of guy anchors
must be far from tower,
requiring more property. May
be unsuitable for populated
areas due to land requirements
Low - Well-suited for urban
areas with limited land
availability.
Height
Moderate
High - Guyed towers may
exceed 366 m (1200 ft.)
Low
Growth Potential
Moderate
Moderate
Low - Monopoles capable of
supporting growth with room to
rent space to other users may
cost significantly more to build.
Rigidity
2.12.1
Moderate based on loading
Low - wind resistance less than
other types.
TOWER DESIGN DRAWINGS
Tower foundation drawings shall show the following information at minimum:
2-18
•
Reference to the soil/geotechnical report, including file number, date and firm performing report,
used in calculations and design.
•
Required concrete compressive strength to be achieved at 28 days
•
Grade and/or type of reinforcing bar
•
Concrete coverage requirements
•
Whether welding of rebar is permitted
•
Whether cold joints are permitted; if so, the joining procedure shall be specified.
•
Whether permanent steel casings are permitted for caisson installations
•
Whether temporary steel casings are or may be required due to the expected soil conditions
•
Any recommended concrete installation techniques such as a tremie
•
References to all codes (and sections of codes) applicable for the design
68P81 089E50 -B
9/1 /05