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<br />e <br /> <br />e <br /> <br />e <br /> <br />The embankment-pavement loss data used to construct table 7.1 were <br />obtained from highway sections 48 feet wide, 40 feet of asphalt pavement, <br />well vegetated 3 to 1 side slopes, and sandy-,lay fill materi.l. T~e <br />data set included estimates for embankment erosion and pavement loss for 0.5, <br />1.0, 2.0, 3.0, 4.0 and 5.0 feet of overtopping. The data for the 0.5 foot <br />condition included estimates of losses for overtopping time from 12 to 72 <br />hours. The data for 1.0 and 2.0 feet of overtopping included estimates for 1 <br />and 72 hours, and the data for 3.0, 4.0 and 5.0 feet of overtopping included <br />estimates for 1 and 60, and 1 and 48 and 1 and 36 hours of overflow, respect- <br />ively. Since the data set for the 0.5 foot of overflow was fairly complete, <br />it was utilized to establish trends for the .other depths of overtopping. <br /> <br />To determine embankment and pavement losses, enter table 7.1 with the time <br />and depth of overtopping to determine the percent of embankment and pavement <br />loss. The time and depth of overtopping for the various flood events are <br />outputs of the hydraulic analysis. The economic losses at the roadway (LAR) <br />are then computed from the equation: <br /> <br />LAR = <br /> <br />E P1C V + <br />[wee <br />48 <br /> <br />+ M <br />c <br /> <br />P P C A <br />w 2 P p]C <br />20 a <br /> <br />E = Embankment width, ft. <br />w <br /> <br />Pl = Percent of embankment loss. <br /> <br />C = Cost of embankment, $/CY. <br />e <br /> <br />V = Total volume of embankment subject <br />e to overflow, CY. <br /> <br />P = Pavement width, ft. <br />w <br /> <br />P2 = Percent of pavement loss. <br /> <br />Cp = <br />Ap = <br /> <br />Cost of pavement, $/SY. <br /> <br />Total area of pavement, subject to <br />overflow, SY. <br /> <br />Ca = Ajustment factor for rapid repair. <br />Mc = Mobilization cost, $. <br /> <br />Example: For the Row Creek crossing, flood frequencies of 10, 25, 50, 100 <br />and 200 are to be used in the analysis. Table 7.la summarizes the time and <br />depth of overtopping analysis, and the percent losses for the embankment and <br />pavement. Table 7.1b summarizes the roadway loss calculations. The costs used <br />were $1.75/CY of embankment and $13.50/SY for pavement. The adjustment <br />factor for rapid repair is 1.3 making the costs $2.27/CY of embankment <br />and $17.55/SY of pavement. The mobilization costs are negligible for the <br />100-year flood event and $5,000 for the 200 year event. <br /> <br />41 <br />