3003 W CASINO RD BLDG 45-06 2025-07-17

SITTS & HILL ENGINEERS, INC. TACOMA, WASHINGTON (253)474-9449 JOB: 17659 DESIGNED: EMF DATE: 03/17/2020 12 PROJECT: SITE PUMPED INDUSTRIAL WASTE CHECKED: BKL DATE: 03/17/2020 Trench Walls and Base Slabs: The trench walls were analyzed for the design loads using the software program Enercalc, and both the trench walls and base slabs were analyzed as retaining walls using the software program RetainPro. Enercalc Analysis: I The trench walls were modeled as cantilever elements in Enercalc.Assuming a 6'-0" wheel group base and a 1:1 load distribution throughout the depth of the trench, the 2'-0" tall wall was modeled as a 4'-0" wide element that resists half an axle load. The wheel loads were applied with eccentricities equal to half the wall thickness. Per the attached Enercalc analysis, 8" thick walls reinforced with #5 vertical reinforcing bars at 9" O.C. are OK to withstand the design loads. RetainPro Analysis: I The trench walls and base slabs were analyzed as retaining walls using the software program RetainPro. Soil and loading properties were assigned to the model according to the values provided in the reference Geotechnical report for the site, attached in Appendix A. Half an axle load was applied as a linear live load to the top of the 2'-0" deep retaining wall, and the distributed loads are calculated below assuming a 1:1 load distribution through the wall to the base of the slab. A surcharge load of 250psf is applied according to AASHTO LRFD Bridge Design Specifications Table 3.11.6.4-2. P _ I wr,L3X2:= 3902 pl 5.33 ft = f The 8" thick trench base slab and walls reinforced with #5 bars at 9" O.C. are adequate for the design loads per the attached RetainPro analyses. The maximum soil bearing pressure was found to be 3386psf, which is deemed to be acceptable given the short term nature of the wheel loading. This assumption is also justified by the maximum allowable mat slab design soil bearing value of 4000psf given in the reference Geotechnical report. I I I I I I