TagMechanically Stabilized Earth(42)

Hart Crowser draft geotechnical engineering report (J-4978-28) prepared for HNTB, December 4, 2000, addressing the Third Runway embankment at Seattle-Tacoma International Airport, SeaTac, Washington. Covers embankment fill materials, slope stability analyses, foundation instability, subgrade improvements, liquefaction analysis (175-year and 475-year seismic events), FLAC deformation modeling, MSE walls (North Satellite Area, West, South), Phase 4 fill,

Memorandum dated November 9, 2000 from Barry Chen, P.E. of Hart Crowser to Jim Thomson, P.E. of HNTB (J-4978-30), reviewing RECo’s 30% design for NSA, West, and South MSE (Mechanically Stabilized Earth) walls for the Third Runway Embankment Project at Sea-Tac Airport. Using SLOPE/W limit equilibrium analyses and FLAC displacement-based modeling, Hart Crowser identified marginal

Draft memorandum J-4978-28 from Hart Crowser (Douglas Lindquist, Barry Chen PhD P.E., Michael Bailey P.E.) to Jim Thomson P.E. at HNTB, dated September 7, 2000, presenting methods and results of liquefaction analyses for the proposed Third Runway embankment and retaining walls at Sea-Tac, Washington. Analyzed 120 borings with Standard Penetration Test (SPT) results from 112

Reinforced Earth Company (job number 8079, designer MJB, dated 09/01/00) design calculations for Port Of Seattle Sea-Tac International Airport, West Wall 181+25. Document covers internal and external stability analysis for a Mechanically Stabilized Earth (MSE) retaining wall structure including design parameters (select backfill φ=37°, γ=0.140 kcf, Ka=0.24858; random backfill φ=35°, γ=0.140 kcf, Ka=0.27269; foundation φ=35°,

Draft memorandum dated August 21, 2000 from Jamie Beaver, Mike Bailey P.E., and Barry Chen P.E. of Hart Crowser, Inc. to Jim Thomson at HNTB (project J-4978-30) providing geotechnical design information for RECo for MSE wall and reinforced embankment fill design for the Third Runway Embankment at Sea-Tac Airport. Document includes minimum factors of safety

Hart Crowser draft subsurface conditions data report (project J-4978.21) prepared for Port Of Seattle and HNTB, June 2000, covering the West MSE (Mechanically Stabilized Earth) Wall for the Third Runway Embankment at Sea-Tac International Airport. Report includes generalized geologic conditions, subsurface soil conditions, consolidation test results, CU and UU triaxial compression test results, hydrogeologic conditions,

Hart Crowser report (J-4978-22) prepared for HNTB, June 2000, analyzing preliminary stability and settlement for subgrade improvements supporting Mechanically Stabilized Earth (MSE) walls at the Sea-Tac Airport Third Runway Project. Covers three MSE wall locations — North Safety Area, West MSE Wall, South MSE Wall — with analysis of subgrade improvement alternatives including overexcavation and

Draft memorandum dated April 10, 2000 from Douglas Lindquist, Barry Chen P.E., and Mike Bailey P.E. of Hart Crowser, Inc. to Jim Thomson P.E. at HNTB regarding seismic basis of design for the Third Runway Project (J-4978-14) at Sea-Tac Airport for the Port of Seattle. Compares 475-year return period (0.36g peak acceleration, 10% probability of

Draft Subsurface Conditions Data Report prepared by Hart Crowser for Port Of Seattle and HNTB, project number J-4978-23, dated April 7, 2000. Covers geologic and subsurface soil conditions, hydrogeologic conditions, auger borings, Standard Penetration Test (SPT) procedures, test pit excavations, and monitoring well installation for the South MSE (Mechanically Stabilized Earth) Wall and Adjacent Embankment

A 1999 memo from the Washington State Department of Ecology evaluates construction techniques for a retaining wall near Miller Creek at Sea-Tac International Airport's Third Runway project. The memo concludes that specialized methods such as tied-back walls, bored piles, soil nailing, or ground freezing can address difficult underground soil conditions while keeping construction within the approved wetlands disturbance footprint, though at significant cost. The author also recommends installing monitoring devices in the wall and backfill to confirm the structure performs as designed throughout its service life.