Bank One-CS030828BROCKETTE •DAVIS • DRAKE, inc.
consulting engineers
August 28, 2003
Mr. Rick O'Dell
City of Keller- Engineering Dept
PO Box 9478
Coppell, Texas 75019
Re: Bank One -Natchez Trace
Coppell, Texas
BDD # C02364
Dear Mr. O'Dell:
It has been brought to our attention that the City of Coppell needs additional clarification on the site
paving design for the above referenced project. For this site, HBC Engineering has recommended using
5"-3000 psi concrete in automobile parking areas and 6"-3500 psi concrete in areas subject to truck traffic
(ref. HBC Report No. 94025435). They do not recommend using lime stabilization in conjunction with
concrete pavement. Based on City of Coppell minimum requirements, we kept those thicknesses in our
design, but raised the required strength for both situations to 4000 psi. This design was reviewed and
approved by the City of Coppell engineering department.
Based on the geotechnical report, we recommend using the higher strength paving (4000 psi) in lieu of
the lime-stabilized subgrade. Lime stabilization is not a cost effective way to prolong the life of concrete
site paving.
Should you have any questions or concerns, please feel free to call me to discuss this matter.
Sincerely,
BROCKETTE-DAVIS-DRAKE, inc.
Brandon W. O'Donald, P.E.
/ab
cc: Shelia Fagg-Acquirre Fax: 972-789-9963
Mark Rouch -Merriman Fax: 214-987-2138
Gvll & So-u¢ural Engineering • Surveying
4144 North Cen oral Expressway, Suice 1100 Dallas, Texas 75204
(214) 824-3647 Civil/Survey Fax (214) 824-7064 Rrucw ral Fax (214) 624-2566