1010 N BROADWAY STARBUCKS 2025-07-24

Geotechnical Engineering Evaluation lierracon Broadway& 10th Starbucks = Everett,WA January 9, 2014 = Terracon Project No. 81135080 Crushed Aggregate Base: We recommend that all CAB material conform to the criteria for "Crushed Surfacing Base Course" per WSDOT: 9-03.9(3). In the interest of using recycled materials from on-site or off-site sources, it would be acceptable to substitute up to 20 percent of the CAB with crushed cement concrete, provided that the final mixture meets the same textural criteria as the aforementioned WSDOT material. Regardless of composition, all CAB material should be compacted to a minimum density of 95 percent, based on the Modified Proctor maximum dry density (per ASTM: D-1557). Asphalt Concrete Pavement: We recommend that the ACP aggregate gradation conform to the control points for a '/2-inch mix (per WSDOT: 9-03.8(6)) and that the binder conform to PG 58-22 criteria (per WSDOT: 9-02.1(4)). We also recommend that the ACP be compacted to a target average density of 92 percent, with no individual locations compacted to less than 90 percent nor more than 96 percent, based on the Rice theoretical maximum density for that material (per ASTM: D-2041). Cement Concrete Pavement: We recommend using Portland cement concrete with a minimum compressive strength of 4,000 psi and a minimum rupture modulus of 580 for the CCP. We also recommend that the concrete be reinforced with a welded wire mesh such as W2-6x6, positioned at a one-third depth within the layer. Compaction Testing: Compaction of the CAB and GSB layers should be verified qualitatively by method observations, proof-rolling, and hand-probing, as well as quantitatively by nuclear densometer testing. Compaction of the ACP should be quantified by laboratory testing of core samples, along with in-situ nuclear densometer testing. Pavement Life and Maintenance: It should be realized that asphaltic pavements are not maintenance-free. The foregoing pavement sections represent our minimum recommendations for an average level of performance during a 20-year design life; therefore, an average level of maintenance will likely be required. Furthermore, a 20-year pavement life typically assumes that an overlay will be placed after about 10 years. Thicker asphalt, base, and subbase courses would offer better long-term performance, but would cost more initially; thinner courses would be more susceptible to "alligator" cracking and other failure modes. As such, pavement design can be considered a compromise between a high initial cost and low maintenance costs versus a low initial cost and higher maintenance costs. The minimum pavement sections outlined above were determined based on the laboratory test results and post-construction traffic loading conditions. These pavement sections do not account for heavy construction traffic during development. A partially constructed structural section may be subjected to heavy construction traffic that can result in pavement deterioration and premature failure. Our experience indicates that this pavement construction practice can result in pavements that will not perform as intended. Considering this information, several alternatives are available to mitigate the impact of heavy construction traffic on the pavement. Reliable 0 Responsive a Convenient a Innovative 13