HomeMy WebLinkAboutSupplemental Foundation Design Recommendations 01.04.2022I Crt ii"slf;'#ürntiÍå**
An Employee Owncd Compony
5020 County Road I54
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
www.kumarusa.com
Office Locations: Denver'(HQ), Par{<er', Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
January 4,2022 RECEIVED
MMME-WG, LLC
Attn: Mark Gould
P.O. Box 130
Glenwood Springs, Colorado 81602
mark@ gouldconstruction. com
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GARFIELD COUNTY
ûOMMUNITY DEVELOPMENT
Project No. l9-7-437
Subject: Supplemental Foundation Design Recommendations, Commercial Development
West of Ami's Acres, Highway 6, Garfield County, Colorado
Gentlemen:
As requested, we have reviewed the proposed building plan to develop foundation design
recommendations for the proposed residence at the subject site. We previously conducted a
subsoil study at the site including exploratory drilling and presented our findings in a report
dated August 20, 2019, Project No. I 9-7-43 7.
The proposed residence will replace the existing structure in the western end of the property near
Boring 1. The building will be single-story wood-frame above a crawlspace. Spread footings
placed on the natural soils are expected for foundation support.
The soils encountered in the exploratory boring consist of medium dense, silty sand and gravel
with cobbles and scaffered boulders. The soils are suitable for spread footing foundation support.
Recommendations for the foundation design are presented below.
1) Footings placed on the undisturbed natural granular soils should be designed for
an allowable bearing pressure of 2,000 psf. Based on experience, we expect
initial settlement of footings designed and constructed as discussed in this section
will be up to about 1 inch. There could be additional differential settlement of
around I inch under wetted conditions and precautions should be taken to keep
the bearing soils dry.
2) The footings should have a minimum width of 18 inches for continuous walls and
2 feet for isolated pads.
3) Exterior footings and footings beneath unheated areas should be provided with
adequate soil cover above their bearing elevation for frost protection. Placement
of foundations at least 36 inches below exterior grade is typically used in this
area.
4) Continuous foundation walls should be heavily reinforced top and bottom to span
local anomalies such as by assuming an unsupported length of at least 14 feet.
Foundation walls acting as retaining structures should also be designed to iesist a
MMME-WG, LLC
January 4,2A22
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lateral earth pressure corresponding to an equivalent fluid unit weight of at least
45 pcf for the onsite sand and gravel soil as backfill.
Existing fill and loose or disturbed soils should be removed and the footing
bearing level extended down to the relatively dense natural granular soils. The
exposed soils in footing area should then be moistened and compacted.
A representative of the geotechnical engineer should observe all footing
excavations prior to concrete placement to evaluate bearing conditions.
The recommendations submitted in this letter are based on the soils encountered by the previous
limited subsurface exploì'ation at the site and our experience in the area. Variations in the
subsurface conditions below the excavation could increase the risk of foundation movement. We
should be advised of any variations encountered in the excavation conditions for possible
changes to recommendations contained in this letter. Our services do not include determining
the presence, prevention or possibility of mold or other biological contaminants (MOBC)
developing in the future. If the client is concerned about MOBC, then a professional in this
special field of practice should be consulted.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, fnc.
Steven L. Pawlak,
SLPlkac
6)
.n 16222
l(umar & Associateg, lnc.6 Projcot l,lo. 19,7-437