ARCHIVED REPORTS_2019 SOIL MGMT PLAN (JULY-REVISED)

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Murphy Parkway Warehouse December 19, 2016 Job No. 146-618 Page 11 type of treatment chemicals to be used should be established by our engineers based on a review of the types of soils present on each area to be treated. All treatment should conform to applicable provisions of the 2010 Caltrans Standard Specifications, Sections 24 and 27, except with regard to compaction as specified above. The treated subgrade should be either kept wet for a period of at least three days after final compaction, or seal coated as recommended in Section 24. Treated soils tend to experience shrinkage and cracking during curing. Such cracking does not affect the strength of the treated materials, but can lead to cosmetic reflective cracking through asphalt concrete. Depending on the degree of cracking, crack sealing or similar maintenance may be required to ensure long term pavement performance. Use of the nominal layer of Caltrans Class 2 aggregate base between the treated soil layer and the asphalt concrete will decrease the incidence of the described shrinkage cracking. Recommended portland cement concrete pavement sections for the traffic indices discussed above are presented in Table 3. TABLE 3 PORTLAND CEMENT CONCRETE SECTION ALTERNATIVES Design Traffic Index Portland Cement Concrete (inches) Class 2 Aggregate Base (inches) Chemically Treated Soil (inches) 6.0 6 2 12 7.0 6.5 2 12 8.0 7 2 12 The aggregate base layer is considered a leveling course and its thickness may be varied in the field for leveling purposes. Chemically treated soil subgrades should be constructed as recommended in the Foundation investigation report. Any one section of Portland cement concrete pavements at depressed loading docks would be expected to support only a few trucks per day, including parking tractor-trailers and inadvertent travel of maneuvering vehicles. Based on this, traffic index 6.0 is considered appropriate for dock pavements. The above portland cement concrete pavement sections are based on use of concrete with a minimum modulus of rupture of 490 pounds per square inch. We anticipate this will require use of concrete with a minimum compressive strength at 28 days of 3000 pounds per square inch. Thickened slab edges should be provided at isolation joints between the concrete pavement and adjacent construction, at the transition from portland cement concrete pavement to asphalt concrete pavement, and adjacent to unpaved areas. The thickened edge should be at least one and one-half inches greater than the unreinforced thicknesses recommended above, and should be tapered back to the design slab thickness over a distance of five feet. Narrow concrete strips used for support of trailer parking dollies should have minimum thicknesses of 7.5 inches, 8 inches, and 8.5 inches in traffic index 6.0, 7.0, and 8.0 areas,