In a portal frame as shown in Figure 1, Type 18-roof sheeting (Table 1) is supported...

 
 
 
 
 
 
 

Transcribed Image Text:

In a portal frame as shown in Figure 1, Type 18-roof sheeting (Table 1) is supported on the Purline Type 5 (Table 2) at 1100 mm centres. The rafter supporting the purlins are to be Section 25 (Table 3) and are at 7 m centres and spanning 12 m. The building dimensions are shown in Figure 1 in which breath (b)= 12 m, depth (d)= 21 m and height=4 m with the roof pitch angle of 6 degree. For the wind load design, please use the Terrain Category 2 in Brisbane with the important level of 3. Table 1. Roof sheeting Type 1 3 2 3 6 7 Name Custom Blue ORB 4 Custom Blue ORB 5 Integrity 820 Integrity 820 Klip-Lok 406 Klip-Lok 406 Klip-Lok 406 8 9 10 11 12 13 14 15 16 17 18 19 Custom ORB Custom ORB BMT Mass (kg/m2) 0.42 0.48 0.6 0.8 0.42 0.48 0.42 0.48 0.6 0.42 0.48 Klip-Lok 700 Klip-Lok 700 Klip-Lok 700 0.6 Klip-Lok 700 Hi-Streng 0.42 Klip-Lok 700 Hi-Streng 0.48 Longline 305 0.7 Spandek Spandek Trimdek Trimdek 0.42 0.48 0.42 0.48 -dm- 4.3 4.9 6.1 8 4.6 5.2 4.9 5.6 6.9 4.6 5.3 6.6 4.7 5.3 9.7 4.7 5.3 4.3 4.9 Table 2. Purlins Purline Type 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Section Mass (kg/m) C/Z100-10 1.77 C/Z100-12 2.11 2.61 3.29 C/Z100-15 C/Z100-19 C/Z150-10 C/Z150-12 C/Z150-15 C/Z150-19 2.43 2.9 3.59 4.51 5.67 4.5 C/Z150-24 C/Z200-15 C/Z200-19 C/Z200-24 C/Z250-19. 5.74 7.21 6.5 8.17 10.18 C/Z250-24 C/Z300-24 C/Z300-30 12.69 C/Z350-30 15.19 hm- Table 3. UB Section Section 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Section Name 610UB125 610UB113 610UB101 530UB92.4 530UB82 460UB82 460UB74.6 460UB67.1 410UBS9.7 410UB53.7 360UBS6.7 360UB50.7 360UB44.7 310UB46.2 310UB40.4 310UB32 250UB37.3 250UB31.4 250UB25.7 200UB29.8 200UB25.4 200UB22.3 200UB18.2 180UB22.2 180UB18.1 180UB16.1 150UB18 150UB14 a) b) c) Find line load G on rafters kN/m Find line load Q on rafters. kN/m Calculate the average roof height (m) have = m d) e) f) Calculate the regional wind speed, VR m/s Calculate Terrain/Height multiplier Mz,cat Submit part Unanswered Submit part Unanswered Calculate the design wind speed Vdes (= V₁x Mz,catx McxMd), Assuming M, M₁ = 1 and Md for worst-case (i.e Cardinal direction to West or South). m/s 81 h) i) Calculate Cpe for rafter near Winward portion of the roof. Calculate Cpe for rafter near leeward portion of the roof. Calculate the area reduction factor ka for the rafter design Submit P Unansw Submit F Unansw Calculate the design external pressure pe for the rafter near the windward portion of the roof (assuming kc = k₁=kp = 1 but consider ką + 1). kPa (Please insert - sign if the pressure is upward). Calculate the design external pressure pe for the rafter near the leeward portion of the roof (assuming kc = k =kp = 1 but consider ka + 1). kPa j) k) Calculate the design internal pressure p; for the rafter using Cpi = 0.7 & -0.3 (assuming kci =1). kpa for Cpi = 0.7 Pi= and Pi= Calculate the design net pressure Pnet for the rafter design Pnet = Pnet = Hence calculate the wind design line loadw, and wd for the rafter. kN/m (Please insert - sign for the pressure to be upward). kN/m W₁ = kpa for Cpi = -0.3 Wd= kPa for uplift pressure (Please insert - sign for the pressure to be upward). kPa for downward pressure j) k) Calculate the design internal pressure p; for the rafter using Cpi = 0.7 & -0.3 (assuming kci =1). kpa for Cpi = 0.7 Pi= and Pi= Calculate the design net pressure Pnet for the rafter design Pnet = Pnet = Hence calculate the wind design line loadw, and wd for the rafter. kN/m (Please insert - sign for the pressure to be upward). kN/m W₁ = kpa for Cpi = -0.3 Wd= kPa for uplift pressure (Please insert - sign for the pressure to be upward). kPa for downward pressure L) Using the ultimate strength limit state design approach, Calculate the most severe line load combinations on a rafter (uplift). kN/m Please insert - sign if the line load is upward. Calculate the most severe line load combinations on a rafter (downward). kN/m 1 1.35G 1.2G+1.5Q 1.2G+ YcQ+Wu 1.2G+ YcQ+Wd 0.9G+Wu 0.9G+Wd In a portal frame as shown in Figure 1, Type 18-roof sheeting (Table 1) is supported on the Purline Type 5 (Table 2) at 1100 mm centres. The rafter supporting the purlins are to be Section 25 (Table 3) and are at 7 m centres and spanning 12 m. The building dimensions are shown in Figure 1 in which breath (b)= 12 m, depth (d)= 21 m and height=4 m with the roof pitch angle of 6 degree. For the wind load design, please use the Terrain Category 2 in Brisbane with the important level of 3. Table 1. Roof sheeting Type 1 3 2 3 6 7 Name Custom Blue ORB 4 Custom Blue ORB 5 Integrity 820 Integrity 820 Klip-Lok 406 Klip-Lok 406 Klip-Lok 406 8 9 10 11 12 13 14 15 16 17 18 19 Custom ORB Custom ORB BMT Mass (kg/m2) 0.42 0.48 0.6 0.8 0.42 0.48 0.42 0.48 0.6 0.42 0.48 Klip-Lok 700 Klip-Lok 700 Klip-Lok 700 0.6 Klip-Lok 700 Hi-Streng 0.42 Klip-Lok 700 Hi-Streng 0.48 Longline 305 0.7 Spandek Spandek Trimdek Trimdek 0.42 0.48 0.42 0.48 -dm- 4.3 4.9 6.1 8 4.6 5.2 4.9 5.6 6.9 4.6 5.3 6.6 4.7 5.3 9.7 4.7 5.3 4.3 4.9 Table 2. Purlins Purline Type 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Section Mass (kg/m) C/Z100-10 1.77 C/Z100-12 2.11 2.61 3.29 C/Z100-15 C/Z100-19 C/Z150-10 C/Z150-12 C/Z150-15 C/Z150-19 2.43 2.9 3.59 4.51 5.67 4.5 C/Z150-24 C/Z200-15 C/Z200-19 C/Z200-24 C/Z250-19. 5.74 7.21 6.5 8.17 10.18 C/Z250-24 C/Z300-24 C/Z300-30 12.69 C/Z350-30 15.19 hm- Table 3. UB Section Section 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Section Name 610UB125 610UB113 610UB101 530UB92.4 530UB82 460UB82 460UB74.6 460UB67.1 410UBS9.7 410UB53.7 360UBS6.7 360UB50.7 360UB44.7 310UB46.2 310UB40.4 310UB32 250UB37.3 250UB31.4 250UB25.7 200UB29.8 200UB25.4 200UB22.3 200UB18.2 180UB22.2 180UB18.1 180UB16.1 150UB18 150UB14 a) b) c) Find line load G on rafters kN/m Find line load Q on rafters. kN/m Calculate the average roof height (m) have = m d) e) f) Calculate the regional wind speed, VR m/s Calculate Terrain/Height multiplier Mz,cat Submit part Unanswered Submit part Unanswered Calculate the design wind speed Vdes (= V₁x Mz,catx McxMd), Assuming M, M₁ = 1 and Md for worst-case (i.e Cardinal direction to West or South). m/s 81 h) i) Calculate Cpe for rafter near Winward portion of the roof. Calculate Cpe for rafter near leeward portion of the roof. Calculate the area reduction factor ka for the rafter design Submit P Unansw Submit F Unansw Calculate the design external pressure pe for the rafter near the windward portion of the roof (assuming kc = k₁=kp = 1 but consider ką + 1). kPa (Please insert - sign if the pressure is upward). Calculate the design external pressure pe for the rafter near the leeward portion of the roof (assuming kc = k =kp = 1 but consider ka + 1). kPa j) k) Calculate the design internal pressure p; for the rafter using Cpi = 0.7 & -0.3 (assuming kci =1). kpa for Cpi = 0.7 Pi= and Pi= Calculate the design net pressure Pnet for the rafter design Pnet = Pnet = Hence calculate the wind design line loadw, and wd for the rafter. kN/m (Please insert - sign for the pressure to be upward). kN/m W₁ = kpa for Cpi = -0.3 Wd= kPa for uplift pressure (Please insert - sign for the pressure to be upward). kPa for downward pressure j) k) Calculate the design internal pressure p; for the rafter using Cpi = 0.7 & -0.3 (assuming kci =1). kpa for Cpi = 0.7 Pi= and Pi= Calculate the design net pressure Pnet for the rafter design Pnet = Pnet = Hence calculate the wind design line loadw, and wd for the rafter. kN/m (Please insert - sign for the pressure to be upward). kN/m W₁ = kpa for Cpi = -0.3 Wd= kPa for uplift pressure (Please insert - sign for the pressure to be upward). kPa for downward pressure L) Using the ultimate strength limit state design approach, Calculate the most severe line load combinations on a rafter (uplift). kN/m Please insert - sign if the line load is upward. Calculate the most severe line load combinations on a rafter (downward). kN/m 1 1.35G 1.2G+1.5Q 1.2G+ YcQ+Wu 1.2G+ YcQ+Wd 0.9G+Wu 0.9G+Wd

Answer rating: 100% (QA)

Solution a Line load on Rafters ... View the full answer