HEC-15 Grass Lining Design

Units: EnglishMetric

Grass cover condition: ExcellentVery GoodGoodFairPoor

Grass growth form: SodBunchMixed

Soil types: Non-cohesiveGM Silty gravelsGC Clayey gravelsSM Silty sandsSC Clayey sandsML Inorganic siltsCL Inorg. clays (Lo PI)MH Inorganic siltsCH Inorg. clays (Hi PI)

Input Flow Q (ft3/s) Stem height h (ft) Bottom Width B (ft) Side slope (1:Z1) Side slope (1:Z2) Grade So (%) D75 (inch): Plasticity index: Void ratio:

Results Depth d (ft): x.xx Mean shear τo (lb/ft2) x.xx Max shear τp (lb/ft2) x.xx Manning's n x.xx Top width T (ft) x.xx Average velocity (ft/s) x.xx Permissible shear stress: Permissible soil shear τp,soil (lb/ft2): x.xx Permissible grass shear τp (lb/ft2) x.xx

Lining is ? Revised: 24 Jan 2018.