Technical information Crab range

F a ç a d e c a l c u l a t i o n s Region 1 2 3 4 Basic value of the reference wind speed v b,0 (m/s) 22 24 26 28 Peak dynamic pressure (metropolitan France): q p(24 m) Where C prob = 1 VN Speed in km/h Region 1 46.9 99.5 Region 2 55.7 108.5 Region 3 65.1 117.3 Region 4 75.6 126.4 Where C prob = 0,92 VN Speed in km/h Region 1 39.6 91.5 Region 2 47.1 99.7 Region 3 55.3 108.1 Region 4 64.1 116.4 Where EW = 1.5 x NW = Normal Wind, EWS = Extreme Wind j E = Fullness of scaffolding No cover Net Cover 0.25 1.00 1.00 No cover Net Cover Drag force factor C t : 0.325 0.213 1.1 Source FFB Echafaudages Dynamic pressure: q=q p xC t xp E Region 1 No cover Net Cover Dynamic pressure with C prob =1 (daN/m 2 ) 3.8 10 51.6 Dynamic pressure with C prob =0.92 (daN/m 2 ) 3.2 8.4 43.6 Region 2 No cover Net Cover Dynamic pressure with C prob =1 (daN/m 2 ) 4.5 11.9 61.3 Dynamic pressure with C prob =0.92 (daN/m 2 ) 3.8 10 51.8 Region 3 No cover Net Cover Dynamic pressure with C prob =1 (daN/m 2 ) 5.3 13.9 71.6 Dynamic pressure with C prob =0.92 (daN/m 2 ) 4.5 11.8 60.8 Region 4 No cover Net Cover Dynamic pressure with C prob =1 (daN/m 2 ) 6.1 16.1 83.2 Dynamic pressure with C prob =0.92 (daN/m 2 ) 5.2 13.6 70.5 Peak dynamic pressure calculated according to EN 1991-1-4 (Eurocode 1, part 4) Peak dynamic pressure is calculated using the following formula: STANDARD FAÇADE Scaffolding in 2.00 m sections No cover Net Cover S a = Anchorage influence area (m 2 ) 16 8 8 Surface of influence Detailed calculations for determining stresses in the anchor ties STANDARD FAÇADE Scaffolding in 2.50 m sections No cover Net Cover S a = Anchorage influence area (m 2 ) 20 10 10 STANDARD FAÇADE Scaffolding in 3.00 m sections No cover Net Cover S a = Anchorage influence area (m 2 ) 24 12 12 161 q p (Z) (daN/m 2 ) = (1 + (7 x ) x 1 / 2 x 1,225 x (V b 2 x C 0 (Z) 2 x (0,19 x ( ) ) 2 x (In ) K I c 0 (Z) x ln ( ) Z z 0 z 0 z 0, II 0,07 z z 0 2 Coefficient of direction: C dir = 1 Coefficient of season: C season = 1 Coefficient of probability: c prob = 1 - K. In (- In (1 - p) n 1 - K. In (- In (0.98)) For: 3 months < Project duration ≤ 1 year, 25-year return period, p = 0.04 C prob = 0.92 For: Project duration > 1 year, 50-year return period, p = 0.02 C prob = 1 Land category IV C r (z = 24 m ) = 0.74 where K r = 0.234 (urban areas with at least 15% of its surface area constructed with buildings the average height of which is more than 15 m) Map of wind zones Design assumptions: façade erected in town with a maximum height of 24 m, against a closed building. With V b = C dir. C season . C prob . V b,0 and C o (Z) = 1 01.11.17 T e c h n i c a l i n f o r m a t i o n