HomeMy WebLinkAboutFile Documents.743 Cemetery Ln.0011.2018 (74).ARBK CITY OF ASPEN
TRAIL CONCRETE SPECIFICATIONS
The City of Aspen follows the basic concrete specifications as listed by COOT in
their reference publication for concrete trail construction:
2005 Colorado Department Of Transportation
"Standard Specifications for Road and Bridge Construction"
(Blue book)
Earthwork-All earthwork shall meet guidelines contained in"Section 200".
Concrete Work All concrete work shall meet the guidelines contained and
described in"Section 601 Structural Concrete"and"Section 608 Sidewalks and
Bikeways"contained in both of the above publications.
Design
• Flatwork design should meet AASHTO,CDOT,ADA, and City of Aspen
Guidelines
• Trail width-10 foot with 1 foot safety shoulders typical
• Cross slope of 2%
• Trail and driveway cross-pans to be concrete 6 inches in thickness
Subgrade-The suitability and structural properties of the subgrade will determine
how the subbase will be designed and constructed. Subgrade will be compacted to
95% modified proctor by others. The Contractor shall inspect all subgrade
preparation prior to concrete pouring for acceptable compaction.
Subbase-The subbase shall consist of 6"of class 6 aggregate base course
Delivery-Discharge concrete transmitted in a truck mixer,agitator or other
transportation device within 11/2 hours after the mixing water has been added.
Deliver concrete to the job in exact quantities required by the design mix. Any
additional water added to the mix after leaving the batch plant shall be indicated on
the truck ticket and signed by the person responsible. Where extra water is added
to the concrete it shall be mixed thoroughly for 40 revolutions of the drum or 31/2
minutes at mixing speed,whichever is greater. Collect delivery or batch tickets
from delivery truck driver and turn them over to the Owner's Representative.
Inspection and Testing-Concrete mixes will be subject to inspection and testing as
required to assure compliance with quality requirements.
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Fibrous Reinforcement-Provide collated,fibrillated,polypropylene fibers
containing no reprocessed olefin materials and having a tensile strength of 70,000
psi for all concrete trail flatwork. Forta CR by Forta Corporation or Fibermesh by
Fibermesh,Inc.
Consolidation-Consolidate concrete during and immediately after depositing by
means of hand-spading,especially at corners and angles of the forms,around
embedded fixtures and other difficult areas. Mechanical vibrators may be used;if
mechanical vibrators are used,a cycle at 12,000 cycles per one minute or more shall
be utilized.
• Do not use vibrators to move or spread concrete.
• Any evidence of lack of consolidation or over-consolidation shall be
regarded as sufficient reason for requiring removal of section involved and
replacement at Contractor's expense.
Finish-Medium broom with trowelled edge.
Joints-Expansion joints shall be every 100 feet or 1000 square feet,whichever is less.
All control joints are to be tooled and shall extend 1/4 of the concrete depth and be
1/8"-1/4"wide. Control joint width shall be consistent throughout the project
scope. Control joints shall be spaced at intervals approximately equal to the trail
width(10 foot spacing).
Curing-Protect all concrete,regardless of temperature,weather or season,from
premature drying for a period of not less than 7 days after concrete is placed.
Where concrete is being protected from freezing,time period for concrete saturation
shall be one day less than that for protection.
Do not open flatwork to pedestrian traffic for at least 24 hours after placement.
Maintain suitable barricades to comply with this requirement.
Drainage-Proper drainage of surface and subsurface waters from the trail cross
section will be required. Minimum of 2% cross slope on finished trail surface.
CONCRETE MIX SPECIFICATIONS
CLASS D WITH 3/4"AGGREGATE MIX DESIGN-FOR 1 CUBIC YARD
• Cement(Type I-II) 592 lb/cu yd
• Fly Ash(Class F) 66lb/cu yd
• 3/4" Coarse Aggregate 1587 lb/cu yd
• 3/8"Aggregate 216 lb/cu yd
• Sand 1138 lb/cu yd
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• Water 35 gal/cu yd
• Water Reducer-W.R.Grace-WRDA-86 4 oz/cwt.
• Air Entrainment W.R.Grace DARAV AIR AT 60 as needed
• Coloring Agent-Davis#5237-SAN DIEGO BUFF 1.5 LB/cu yd.
• Ployfiber-FIBERMESH 1.5 LB/cu yd.
COMPRESSIVE STRENGTH
• 28 day Breaks 4500 PSI min.
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