HomeMy WebLinkAboutPermit Field Test & Inspection Report 2008-4-22
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I K & A Engineering, Inc.
3327 Roanoke Ave., Eugene, OR 97408
(541) 684-9399 Voice
(541) 684-9358 FAX
engineering
April 22, 2008
Project: 7.08
Greg Larking, River Valley BUilders, Inc
POBox 832
Sweet Home, OR 97386
Subject Porch retaining wall-lower floor
Springfield permit no COM2008-00161
418 Mou ntlangate Dnve, Spnngfleld, Oregon
PURPOSE AND SCOPE
Our understanding IS that you are proposing modifYing the lower level floor system located underneath the
upper front entry The original permitted deSign specified a concrete slab-an-grade This slab-an-grade was to
be cast directly against the 18-foot long retaining wall that IS part of the east perimeter foundation and supports
the front entry wall and upper floor. The retaining wall was deSigned as a restrained wall system uSing the slab
for resistance to sliding I
Your proposal IS to construct a framed floor supported by a post or Cripple w~1I system bUilt on the Intenor
footing of the retaining wall Without the slab-on-grade floor resistance to sliding of the wall must be achieved
by other means The purpose of this letter IS to summarize our analysIs and make recommendations for wall
stability without the slab-an-grade lower floor
RECOMMENDATIONS
Without the slab-an-grade lower floor, sliding resistance Will be proVided by the adjacent perpendicular retaining
walls on each end of the 18-foot wall segment. However, with removal of the deSign ed slab-an-grade floor,
restraint of the east penmeter retaining wall underneath the entry must stili be, proVided to minimize toe footing
pressure
We recommend that the framed floor can proVide the necessary restraint If the floor IS constructed tight against
the InSide face of the retaining wall The rim for the floor should consist of a treated 2x12 should have good
contact With the wall face The floor JOiStS should be oriented perpendicular to the retaining wall and have a
tight fit against the treated nm The floor sheathing should consist of 1 1/8" floor decking nailed to the jOists
uSing 10d nails at a 6-Inches 0 c
Thank you for the opportunity to be of service Please call If you have any
questions
Sincerely,
~~
Michael Remboldt, P E
K & A Englneenng, Inc
EXPIRES IY3/fr