OCR Text |
Show 11 Slope break in gulleys: 2 ( s i n ^ o - y c o s V> o) 2 R F = R F u u i • , . N ° ° ( s m i|) u - y cos i|^ u) The desired flow thickness, d , is obtained by trial in analogous manner with the table for calculating flow thickness in gulleys. The subscript u refers to gulley below the break; o to gulley above the break. , Flowing avalanche: - Gulley ( according to Salm): v2 = t% R ( sin ^ - JUL cos ft) - Slopes: v2 = ^ d ( sin f- - JJ. Cos ~ ij) see under d-^ v max=^ di^ f (/ A=°) The maximum velocity is acheived over a relatively short part of the pathl s0 ^ j 25 d1 - Powder avalanche: v2-- * 9 d . | - TL - 1.25 ( kg/ m3)* - 5 Limits of the mean deposition depth: d„ d. 1 -< da <- d. 1. + when 2 4g d = d, + -, ^ ; a 1 4g AQ cos IJJU p, Salm's resistance factor, varies from 2 to 3 [ Editorial comment: use 2 when debris cannot spread laterally; 3 when it can]. * Use YL * 1 ° f° r Colorado and other locations where elevation ^ 10,000 feet ( 3000 m) |