James Building Wind Load Analysis.docx

WIND LOAD ANALYSIS

Considering the structure is an enclose building located in Polomolok, South Cotabato:

30˚

h=7.84m

6.4m

10m

1. Occupancy Category of the Building The building is determined to be categorized as IV Standard Occupancy as per Section 103, NSCP 2015 7th Edition. 2. Basic Wind Speed Considering the location of the building is in Polomolok, South Cotabato, the basic wind speed V is determined to be: V=290 kph = 80.56 m/s as per Section 207A.5.1, NSCP 2015, 7th Edition illustrated in Figure 207A.5-1A

3. Wind Load Parameters

a. Wind Directionality Factor Considering the structure is a building, under MWFRS 𝐾𝒅 = 𝟎. 𝟖𝟓 as per Section 207A.6 referring to Table 207A.6-1 (NSCP 2015 7th Edition) b. Exposure Category Considering that the structure location is in Polomolok, South Cotabato, its ground surface roughness is determined to be categorized as Surface Roughness B: Urban and Suburban Areas, wooded areas, or other terrain with numerous closely spaced obstructions having the size of single-family dwellings or larger (Section 207A.7.2) Moreover, exposure category is determined to be Exposure B as per Section 2017A.7.3.

c. Topographic Factor 𝐾𝑧𝑡 = 1.0 since site conditions and locations of structures do not meet all the conditions specified in Section 207A.8.1

d. Gust Effect Factor

G = 0.85 since the structure is considered rigid (Section 2017 A.9.1). The structure is determined to be rigid since it is considered a lowrise building (Section 207A.9.2, NSCP 2015 7th Edition). Moreover, the structure is considered low-rise building since it comply the conditions specify in Section 207A.2.

e. Enclosure Classification

The structure is classified as enclose since the structure comply the conditions in Section 207A.2, NSCP 2015 7th Edition.

f. Internal Pressure Coefficient 𝐺𝐶𝑝𝑖 = ±0.18 for enclosed buildings (MWFRS) referred in Table 207A.11-1 4. Velocity Pressure Exposure Coefficient 𝑲𝒉 and 𝑲𝒛 Referring to Table 207B.3-1, NSCP 2015 7th Edition For 0 ≤ z ≤ 4.5,

𝐾𝑧 = 0.57

For 4.5 ≤ z ≤ 6.0

𝐾𝑧 = 0.62

For 6.0 ≤ z ≤ 6.4

𝐾𝑧 = 0.63

2

Using 𝐾ℎ = 2.01(ℎ/𝑧𝑔 )𝛼

where

𝑧𝑔 = 365.76 for Exposure B α = 7.0 for Exposure B 2

For h=7.84

𝐾ℎ = 2.01(7.84/365.76)7 = 0.67

5. Velocity Pressure 𝒒𝒉 or 𝒒𝒛 𝑞𝑧 = 0.613𝐾𝑧 𝐾𝑧𝑡 𝑉 2 For 0m ≤ z ≤ 4.5m 𝑞𝑧 = 0.613(0.57)(1.0)(80.56)2 = 2267.640711 For 4.5m ≤ z ≤ 6.0m 𝑞𝑧 = 0.613(0.62)(1.0)(80.56)2 = 2466.556563 For 6.0m ≤ z ≤ 6.4m 𝑞𝑧 = 0.613(0.63)(1.0)(80.56)2 = 2506.339733 For h = 7.84m 𝑞ℎ = 0.613(0.67)(1.0)(80.56)2 = 2665.472415 6. External Pressure Coefficient 𝑪𝒑

h/L =

7.84 10

= 0.784

Windward Wall 𝐶𝑝 = 0.8 Leeward Wall 𝐶𝑝 = −0.5

Windward Roof 𝐶𝑝 = (−0.2,0.2)

Leeward Roof 𝐶𝑝 = −0.6

7. Wind Pressure p = qG𝐶𝑝 -𝑞𝑖 (𝐺𝐶𝑝𝑖 ) where q = 𝑞𝑧 for windward walls evaluated at height z from the ground. q = 𝑞ℎ for leeward walls, side walls, and roofs, evaluated at height h. 𝑞𝑖 = 𝑞ℎ for windward walls, sidewalls, leeward walls and roofs of enclosed building and for negative internal pressure evaluation in partially enclosed building. G = GUST EFFECT FACTOR. 𝐶𝑃 = external pressure coefficient (𝐺𝐶𝑃𝑖 ) = internal pressure coefficient. Windward Wall For 0m ≤ z ≤ 4.5m p = 𝑞𝑧 G𝐶𝑝 -𝑞ℎ (𝐺𝐶𝑝𝑖 ) p = (2267.640711)(0.85)(0.8)-(2665.472415)(0.18) = 1062.21 pa p = (2267.640711)(0.85)(0.8)-(2665.472415)(-0.18) = 2021.78 pa For 4.5m ≤ z ≤ 6.0m p = 𝑞𝑧 G𝐶𝑝 -𝑞ℎ (𝐺𝐶𝑝𝑖 ) p = (2466.556563)(0.85)(0.8)- (2665.472415)(0.18) = 1197.47 pa p = (2466.556563)(0.85)(0.8)- (2665.472415)(-0.18) = 2157.04 pa

For 6.0m ≤ z ≤ 6.4m p = 𝑞𝑧 G𝐶𝑝 -𝑞ℎ (𝐺𝐶𝑝𝑖 ) p = (2506.339733)(0.85)(0.8)- (2665.472415)(0.18) = 1224.53 pa p = (2506.339733)(0.85)(0.8)- (2665.472415)(-0.18) = 2184.10 pa

Leeward Wall p = 𝑞ℎ G𝐶𝑝 -𝑞ℎ (𝐺𝐶𝑝𝑖 ) = 𝑞ℎ (G𝐶𝑝 -(𝐺𝐶𝑝𝑖 )) p = 2665.472415 [(0.85)(-0.5)-(0.18)] = -1612.61 pa p = 2665.472415 [(0.85)(-0.5)-(-0.18)] = -653.04 pa

Windward Roof p = 𝑞ℎ G𝐶𝑝 -𝑞ℎ (𝐺𝐶𝑝𝑖 ) = 𝑞ℎ [G𝐶𝑝 -(𝐺𝐶𝑝𝑖 )] p = 2665.472415 [(0.85)(-0.2)-(0.18)] = -932.92 pa p = 2665.472415 [(0.85)(-0.2)-(-0.18)] = 26.65 pa

p = 2665.472415 [(0.85)(0.2)-(0.18)] = -26.65 pa p = 2665.472415 [(0.85)(0.2)-(-0.18)] = 932.92 pa Leeward Roof p = 𝑞ℎ G𝐶𝑝 -𝑞ℎ (𝐺𝐶𝑝𝑖 ) = 𝑞ℎ [G𝐶𝑝 -(𝐺𝐶𝑝𝑖 )]

p = 2665.472415 [(0.85)(-0.6)-(0.18)] = -1839.18 pa

p = 2665.472415 [(0.85)(-0.6)-(-0.18)] = -879.61 pa

1839.18 Pa 1.44 m

932.92 Pa

0.5 m

2157.04 Pa

2021.78 Pa

4.5 m

6.4 m

2184.10 Pa

1.5 m

30˚

10m

1612.61 Pa