Design & Sizing第 19 / 110 题
A roof drains 4,800 ft^2 at a design rainfall rate of 4 in/hr. Using Q = 0.0104 x A x i, what is the storm design flow?
a.150 gpm
b.250 gpm
c.200 gpm
d.320 gpm
解析
Q = 0.0104 x 4,800 x 4 = 199.7 gpm, about 200 gpm. Doubling the rainfall rate doubles the flow for the same roof, which is why the local 100-year rainfall intensity is critical to storm sizing. This flow selects the leader and storm drain sizes.
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