HomeMy WebLinkAboutCDP 97-23; SFR - 2701 Ocean St; Limited Geotechnical Reconnaissance; 1997-07-23BARRY AND ASSOCIATES
GEOTECHNlCAL ENGlNEERlNG
P.O. Box 230348
Encinitas, CA 92023-0348
(61 9) 753-9940
July 23, 1997
Mr. Morton S. O'Grady, Architect 4407 Manchester Ave. Suite 206 Encinitas, California 92024
Sub j ect : LIMITED GEOTECHNICAL RECONNAISSANCE Addition to Single Family Residence
2701 Ocean Street
Carlsbad, California
Owner: William C. Mann
Reference: 1. Plans Prepared By: Morton S. O'Grady, Architect
Dated 6/3/97
2. Limited Soils Investigation
Existing Steinhart Residence
2701 Ocean Street
Carlsbad, California 92008 Dated June 14, 1988
Dear Mr. O'Grady,
In response to your request, we have performed a limited geotechnical reconnaissance at the subject site for the proposed addition to the existing residence as shown on the referenced plans.
- The findings of our reconnaissance and recommendations are
presented in this report.
- From a geotechnical point of view, it is our opinion that the
addition as shown on the referenced plans can be accomplished
without impacting the slope stability as it presently exists,
provided the recommendations in this report are implemented during
the design construction phases. -
If you have any questions, please do not hesitate to contact us at
(760) 753-9940.
July 23, 1997
Page 2
W.O. #P-l514
INTRODUCTION
This report presents the results of our limited geotechnical
reconnaissance. The purpose of the study is to evaluate general
conditions as they may relate to impacting the slope stability
adjacent to the beach, and to obtain sufficient information to
assign an allowable soil bearing value for the proposed footings.
SITE CONDITIONS
The subject property is located on the west side of Ocean Street
the second lot south of the intersection of Beech Avenue and Ocean
Drive, in the City of Carlsbad California.
The property includes a single family residence with garage and
rear deck.
PROPOSED ADDITIONS
Plans for the additions include a 5.0' extension of the main level
and upper level south wall with new continuous footings and
supporting columns, a new two car garage, planter, and relocation
of exterior railing.
SITE INVESTIGATION
The investigation consisted of a visual reconnaissance of the
property and review of the referenced Limited Soils Investigation
prepared by Southern California Soils and Testing.
July 23, 1997
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W.O. #P-l514
CONCLUSIONS AND RECOMMENDATIONS
General
Based on the results of our reconnaissance, review of the available
documents, and knowledge of the immediate area we conclude that
the on site soils are suitable for the support of the proposed
additions, provided the recommendations in this report are
implemented during the design and construction phase.
Foundation
Footings for the proposed additions should be a minimum of 15
inches wide and founded a minimum of 18 inches below grade. A 12-
inch-by-12-inch grade beam should be placed across the garage
opening.
Footings founded a minimum of 18 inches below grade may be designed
for a bearing value of 1500 psf.
The bearing value indicated above is for the total of dead and live
loads. This value may be increased by 33 percent for short
durations of loading, including the effects of wind and seismic
forces.
Resistance to lateral load may be provided by friction acting at
the base of foundations and passive earth pressure. A coefficient
of friction of 0.3 should be used with dead-load forces. A passive
July 23, 1997
Page 4
W.O. #P-l514
earth pressure of 250 pounds per square foot, per foot of depth of
fill penetrated to a maximum of 1500 pounds should be used in the
design.
Minimum steel reinforcement should consist of 4-#4 bars, 2 placed
3" from the bottom of the footing and 2 placed below the top of the
footing .
Garase Slab on arade
Slab on grade should be a minimum of 4 inches thick and reinforced
in both directions with #3 bars, placed 18 inches on center each
way, or #4 bars placed 24" on center each way. Utility trenches
underlying the slab should be bedded in clean sand to at least one
foot above the top of the conduit, then backfilled with the on-site
granular materials, compacted to a minimum of 90 percent of the
laboratory maximum dry density. However, sufficiently compacting
the backfill deposits may damage or break shallow utility lines.
Therefore, minor settlement of the backfill in the trenches is
anticipated in these shallow areas. To reduce the possibility of
cracks occurring, the slab should be provided with additional
reinforcement to bridge the trenches.
Drainaqe
All roof water should be collected and conducted to the street via
non-erodible devices. Roof gutters are recommended. Pad water
July 23, 1997
Page 5
W.O. #P-1514
should be directed away from foundations and around the residence
to a suitable location. Pad water should not pond.
Footinq Inspections
Structural footing excavations should be inspected by a
representative of this firm during excavation. Additional
recommendations may be made at that time.
LIMITATIONS
If conditions encountered during construction appear to differ from
those described in this report, our office should be notified so
that we may consider whether modifications are needed. No
responsibility for construction compliance with design concepts,
specifications or recommendations given in this report is assumed
unless on-site review is performed during the course of
construction.
The professional judgments presented herein are founded partly
on our assessment of the technical data gathered, partly on our
understanding of the proposed construction and partly on our
general experience in the geotechnical field. Our engineering work
and the judgments given meet present professional standards.
July 23, 1997
Page 6
W.O. #P-l514
If you have any questions, please do not hesitate to contact our
office at 753-9940.
The opportunity to be of service is greatly appreciated. -
Respectfully submitted,
A.R. BARRY AND ASSOCIATES -