HomeMy WebLinkAboutASCENT STUDIO CLIMBING & FITNESS - FDP - FDP150023 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTTerracon Consultants, Inc. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado 80525
P [970] 484-0359 F [970] 484-0454 www.terracon.com
October 28, 2014
revised: November 11, 2014
Ascent Studio Climbing and Fitness
2509 Doolittle Court
Fort Collins, Colorado 80526
Attn: Mr. Jon Lachelt
E: jon.lachelt@gmail.com
Re: Infiltration Rate Testing for Permeable Pavements
Ascent Studio Climbing Gym
2121 and 2127 South Timberline Road
Lots 12 and 13, Timberline Center
Fort Collins, Colorado
Terracon Project No. 20145015
Dear Mr. Lachelt:
Previously, Terracon Consultants, Inc. (Terracon) prepared a Geotechnical Engineering Report
(Project No. 20145015; report dated May 7, 2014) for the project referenced above. We
understand a portion of the pavements planned for this project will be permeable. Terracon
performed double-ring infiltrometer field testing to assist the project team with design. The
testing was conducted in the area proposed for porous pavements as shown on Figure 1.
Testing was performed in general accordance with ASTM D3385.
Terracon retained the services of an excavation company to excavate an approximately 5 foot
wide by 6 foot long by 4½ foot deep testing area. The soils observed in the test pit were similar
to those encountered during our previous study at this site consisting of about 2 feet of dark
brown silty clay fill with gravel and cobbles underlain by silty lean clay with varying amounts of
sand.
The average in-field infiltration rate was calculated to be 0.302 inches per hour. The calculated
infiltration rate is within published ranges for the soil type encountered on this site and is
considered to be a representative value.
Pavements – Porous Pavers Subgrade Preparation
Unlike conventional pavements, porous pavement subgrades are not compacted. When
preparing the subgrade for porous pavements, care should be taken to excavate the required
reservoir storage volume without disturbing the underlying soils. It may be prudent to scarify the
subgrade soils prior to placement of the materials for the rock reservoir.
Supplemental Geotechnical Engineering Report
Ascent Studio Climbing Gym ■ Fort Collins, Colorado
November 11, 2014 ■ Terracon Project No. 20145015
Responsive ■ Resourceful ■ Reliable 2
Groundwater was previously encountered at depths of about 22 and 23 feet below existing site
grades in the portion of the site planned for porous pavers. We do not believe groundwater will
impact the proposed porous pavers planned for this site.
Recommended minimum pavement sections are provided in the table below.
Traffic
Area
Alternative
Recommended Pavement Thicknesses (Inches)
Asphaltic
Concrete
Surface
Aggregate Base
Course
Portland
Cement
Concrete
Porous
Pavers1 Total
Automobile
parking
areas
(light-duty)
A 3½ 6 -- - 9½
B -- -- 5 - 5
C -- 3 -- 3⅛ 6⅛
Heavy
truck traffic
areas
(heavy-
duty)
A 4 8 -- - 12
B -- -- 6 - 6
C
2
-- 5 -- 3⅛ 8⅛
1. Actual thickness of porous pavers may vary depending upon the permeable pavement system selected.
2. Minimum base course thickness with a stone sub-base.
Terracon recommends the design and construction of porous pavers should be completed by a
specialty contractor who has demonstrated experience with placing, compacting, finishing,
edging, jointing, and protecting porous pavers. There are several choices for base course
depending upon which type of porous paver is chosen. Terracon recommends constructing
perimeter curbing around porous pavers and between conventional and porous pavers to
reduce infiltration of water below moisture sensitive subgrades.
Pavements – Maintenance
Preventative maintenance should be planned and provided for an ongoing pavement
management program in order to enhance future pavement performance.
Porous pavers require periodic inspection and cleaning. Consideration should be given to
installing signage to restrict heavily loaded vehicles (i.e. trash trucks, delivery trucks, etc.) from
driving on porous paver areas. Also, maintenance of porous pavers should be completed by
properly trained workers.
The recommendations presented in this report should be used in conjunction with our original
geotechnical engineering report for the Ascent Studio Climbing Gym.
1
20145015
10/28/2014
EDB
BCR
EDB
EDB
1” = 25’
Project Manager:
Drawn by:
Checked by:
Approved by:
Project No.
Scale:
File Name:
Date:
Figure
DIAGRAM IS FOR GENERAL LOCATION
ONLY, AND IS NOT INTENDED FOR
CONSTRUCTION PURPOSES
0’ 13’ 25’
APPROXIMATE SCALE
Approximate In-field
Infiltration Testing Location
1
LEGEND
1
1901 Sharp Point Dr Suite C
Ft. Collins, CO
EXPLORATION PLAN
Ascent Studio Climbing Gym
2121 and 2127 South Timberline Road
Fort Collins, Colorado