2600 FEDERAL AVE 2021 PORT OF EVERETT 2025-09-29

Substantive Requirements Review Landau Associates base course section should be overlaid by 9 inches of HMA. This multi-layer geogrid reinforcement is especially important in the northeast corner of the site, where existing H-piles and concrete pile caps are present at elevations of 16 to 18 ft North America Vertical Datum of 1988. 3.3.3 Single-Layer Geogrid Reinforcement Pavements in areas with limited occurrences of buried structures, within approximately 4 ft of finished grades should be constructed with a single layer of Tensar TX7 geogrid (or similar), placed atop a subgrade that is compacted to a firm, unyielding condition. Twelve inches of well-compacted CSBC should be placed atop the geogrid, followed by 9 inches of HMA. In areas of the site where foundation wall and other miscellaneous structures remain, a 4-meter-wide roll of geogrid should be centered over the remaining structures to limit reflective cracking or differential settlement along these linear features. Single-layer geogrid reinforcement is anticipated to be most applicable in the east-central portion of the site, as shown on Figure 8. 3.3.4 Pavement Construction Materials Asphalt concrete should be compacted to at least 91 percent of the Rice density. Base course material should consist of CSBC, per Section 9-03.9(3) of the 2020 WSDOT Standard Specifications. The base course material should be compacted to at least 95 percent of the MDD. To facilitate fine surface grading, the upper 2 inches of crushed surfacing should consist of crushed surfacing top course (CSTC), per Section 9-03.9(3) of the 2020 WSDOT Standard Specifications. Prevention of road-base saturation is essential for pavement durability; efforts should be made to limit the amount of water entering the base course. CSBC and CSTC should be placed and compacted in accordance with the requirements in Section 2-03.3(14)C of the 2020 WSDOT Standard Specifications. 3.3.5 Reduced Pavement Section A temporary, reduced pavement section may be installed across 6.5 acres of the site. The reduced pavement section would consist of 2 inches of HMA over 12 inches of crushed rock base course. The concept of an 18-kip equivalent single-axle load (ESAL) was used to evaluate the performance of the reduced pavement section.Tensar's SpectraPave Design Software was used to calculate the maximum ESAL value for the reduced pavement section. The following parameters were assumed: • 95 percent reliability. • 20-year design life. • Standard deviation of 0.49. (The American Association of State Highway and Transportation Officials recommends a standard deviation of 0.40 to 0.50 for flexible pavement design.) • Initial serviceability of 4.2. • Terminal serviceability of 2. • Subgrade California Bearing Ratio of 4 percent. Geotechnical Engineering Report 0121049.040.041 Norton Terminal Development&MTCA 3rd Interim Action 3-6 May 7,2021