Park West CC(18)-CS 891016 (2) MASON
JOHNSTON
& ASSOCIATES, INC.
~ geotechnical consultants
Raymond C. Mason. P.E.
16 October 1989 Chainnen~theBoard
Aubrey D. Henley. R.G., C.E.G.
President
John W. Johnston, P.E,. ·
Prentiss Properties Limited, Inc.
1 5 R 0 LBJ Freeway William o. naniean, R.G.
~fce Pmsidem
Dallas, texas 75234 W. Ja~Crome~.,
~ce ~%,sident
Attention: Mr. Lee Hansen Richan~C. Mason
Conwoller
Re: Pavement Design
Site No. 1
Park West Commerce Center
~J No. 5003
Gentlemen:
The following is our design for subgrade in paved areas for
Site No. 1 at Park West Commerce Center. We believe that the
moisture condition of the near-surface soils at tne site is
advantageous for supporting all paving on the existing subgrade
with the following preparation:
1. maintain natural moisture content of near-surface clays
(about 26 percent or above), and maintain in situ dry
density at or aoove 92 to 9U percent of the density
specified below or scarify and recompact the'upper o
inches of the subgrade to 92 to 98 percent of the
maximum dry density determined by ASTM D 698 and at a
moisture content 0 to 4 percentage points above optimum
moisture content determined by that test,
and
2. provide a geotexti£e memorane (such as Mirafi 600X or
700X or similar) on the subgrade along and about I foot
either side of all construction and expansion-joints.
We believe that this procedure will provide a suitable subgrade
for paving, including fire Lanes, at this site. Please call us
if you have any questions.
y truly yours,
~' '.., --,,-.. ..?' '~ · -
t.~y: aoaes .t'~ Mason-Johnston & Assoc., Inc.
J'WJ: lw ~,
235 Morgan Ave., Dallas, Texas 75203-1088 (214) 941-3808