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DESIGN MANUAL& KEYWALL OPERATING GUIDED3H:1V SLOPING SURCHARGE AASHTO METHODOLOGIESSummaryThe hand calculations verify the attached computer output. The data and methods conform to theAASHTO design methods as outlined in the Keystone Design Manual.The internal stress analysis for a sloping backfill was calculated two ways: 1) AASHTO 96 uses a slopingbackfill earth pressure coefficient and 2) AASHTO Simplified uses a level earth pressure coefficient andadds the slope as an equivalent surcharge. All other items of the design remain the same.Caution: AASHTO designs can be very tricky since the design code has changed almost every year since1992. Each highway department has different state specification requirements and modifications to thevarious AASHTO editions. Many items are controversial and not fully addressed. Items such as batteredwall design, connection strength evaluation, minimum reduction factors, barrier loadings and various otherdesign and performance constraints must be reviewed for each project. KeyWall can not comply with allthese AASHTO variations without the User properly determining and selecting the parameters and designconstraints within the software for each project.D.13