Week 10 Challenge
To calculate the snow load accumulated on the bridge according to the Indian Road Congress (IRC) code, we need to consider the design parameters specified in the code. The IRC code provides guidelines for determining the snow load on structures in India.
The snow load on a bridge is calculated using the following formula:
P = Cs * Cz * Pf * Pe * Iw * S
Where: P = Snow load on the bridge (kN/m²) Cs = Shape coefficient Cz = Elevation coefficient Pf = Thermal coefficient Pe = Exposure coefficient Iw = Importance factor for the bridge S = Snow load on the ground (kN/m²)
Given: Span of the bridge (Length) = 10m
Width of the bridge = 14m
Depth of accumulation of snow = 1250mm = 1.25m
First, let's calculate each coefficient step by step:
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Shape coefficient (Cs): Since the deck of the bridge is flat with B < 30 degrees, we can assume a shape coefficient (Cs) of 1.0.
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Elevation coefficient (Cz): According to IRC, for an elevation below 1000m, the coefficient is 1.0.
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Thermal coefficient (Pf): Given that the snow is settled snow, the thermal coefficient (Pf) is 1.0.
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Exposure coefficient (Pe): For an average exposure, the coefficient (Pe) is 1.0.
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Importance factor (Iw): Assuming no specific importance factor, the importance factor (Iw) is 1.0.
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Ground snow load (S): As per IRC for flat terrain and settled snow, IRC provides a ground snow load (S) of 0.85 kN/m².
Now, let's substitute the values into the formula:
P = Cs * Cz * Pf * Pe * Iw * S
P = 1.0 * 1.0 * 1.0 * 1.0 * 1.0 * 0.85 kN/m²
Snow load (P) = 0.85 kN/m²
To find the total snow load on the bridge, we need to multiply the snow load per unit area by the area of the bridge deck.
Total Snow Load = P * Area
Area = Length * Width
Area = 10m * 14m Area = 140m²
Total Snow Load = 0.85 kN/m² * 140m²
Total Snow Load = 119 kN
Therefore, the snow load accumulated on the bridge is 119 kN according to the guidelines provided in IRC.