Div. B › Part 4 › 4.1 › 4.1.6 — Loads Due to Snow and Rain

4.1.6.12 — Valleys in Curved or Sloped Roofs

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(1) For valleys in curved or sloped roofs with a slope α >10°, in addition to the full and partial load cases defined in Article 4.1.6.3., the non-uniform load Cases II and III described in Sentences (2) and (3) shall be considered to account for sliding, creeping and movement of meltwater.
(2) For Case II as shown in Figure 4.1.6.12., the accumulation factor, Ca, shall be calculated as follows:
C_a = 1 / C_b for 0 < x ≤ b/4, and C_a = 0.5 / C_b for b/4 < x ≤ b/2
where,
x =horizontal distance from the bottom of the valley, and
b =twice the horizontal distance between the bottom of the valley and the peak of the roof surface under consideration.
(3) For Case III as shown in Figure 4.1.6.12., Ca shall be calculated as follows:
C_a = 1.5 / C_b for 0 < x ≤ b/8, and C_a = 0.5 / C_b for b/8 < x ≤ b/2
where,
x, b =as specified in Sentence (2).
Tables & Figures referenced
Table 4.1.6.12 : Snow Loads in Valleys of Sloped or Curved Roofs (1),(2) : Forming Part of Sentences 4.1.6.12.(2) and (3)
Loading Figure 4.1.6.12…
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