Bearing Capacity & Settlement The bearing capacity of the footings are governed by settlement The attached chart shows the estimated range of settlements under a single strip footing. The estimated settlement represents the short-term settlement of the soil cover (negligible) and the underlying waste, under the structural load from the solar panel frame. The settlement does not include the long-term settlement of the waste due to creep, degradation etc. The chart shows the estimated settlement for strip footings of increasing width, ranging from 18 inches to 3 feet, for two different bearing pressures: 500 psf and 1000 psf. Settlements are given as a range rather than a single value to account for the uncertainty associated with waste compressibility. The Structural Engineer can use the chart to size the footing based on the dead load of the structure and the tolerable settlement. Because of the variability of the soil cover thickness and the non-homogeneity of the waste, the differential settlement between adjacent footings may be considered to be nearly the same as the total settlement. The allowable bearing pressure may be increased by one third for short term wind or seismic loading conditions. However the resulting short-term load combinations used in design must fall within the middle one-third of the base of the foundation. Design of foundation should also consider sliding and overturning Suji

Suji Somasundaram, PhD, PE, GE. | Principal Engineer

Main: 949-379-2450 | Direct: 949-379-2465 | Fax: 949-379-2470 suji@aesciences.com

Advanced Earth Sciences, Inc. 9307 Research Drive | Irvine, CA 92618

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Bearing Pressure 500 psf, Cr(cover)=0.01, Cc (waste)=0.12Bearing Pressure 500 psf, Cr(cover)=0.01, Cc (waste)=0.25Bearing Pressure 1000 psf, Cr(cover)=0.01, Cc (waste)=0.12Bearing Pressure 1000 psf, Cr(cover)=0.01, Cc (waste)=0.25

Bearing pressure = 500 psf

Bearing pressure =1,000 psf

Footing width (ft)

Analysis 1.5 2 3

Bearing Pressure 500 psf, Cr (cover)=0.01, Cc (waste)=0.12 0.67 0.87 1.26

Bearing Pressure 500 psf, Cr (cover)=0.01, Cc (waste)=0.25 1.20 1.60 2.37

Bearing Pressure 1000 psf, Cr (cover)=0.01, Cc (waste)=0.12 1.19 1.55 2.25

Bearing Pressure 1000 psf, Cr (cover)=0.01, Cc (waste)=0.25 2.19 2.91 4.35

Figure 1 11-15

Estimated Range of Settlement Under Single Strip Footing

(Due to Structural Load)

Milliken Landfill Solar Panels

Project No.: 15-106

Notes: 1. Footing founded on surface (zero embedment) 2. Average soil cover thickness of 4 feet was assumed 3. Settlement estimates are based on typical compressibility values for fine grained soil

cover and municipal solid waste 4. Settlement does not include long term settlement of waste due to self-weight, creep,

degradation etc.