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Calculate the full flow capacity in m³/s (accurate to four dec.pl.) of a 525mm diameter concrete stormwater sewer pipe that has a 1.0% slope.

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Final answer:

The full flow capacity of a 525mm diameter concrete stormwater sewer pipe with a 1.0% slope is approximately 0.8787 m³/s, calculated using the Manning formula for circular pipes flowing full.

Step-by-step explanation:

To calculate the full flow capacity of the 525mm diameter concrete stormwater sewer pipe, we can apply the Manning equation, which is a common approach for such calculations in civil engineering subject. The Manning formula for circular pipes flowing full is given as:

Q = (1/n) * A * R2/3 * S1/2

Where:

First, we need to convert the given diameter from millimeters to meters:

D = 525 mm = 0.525 m

Next, calculate the cross-sectional area of the pipe (π * (D/2)²):

A = π * (0.525 m / 2)² ≈ 0.2165 m²

Because the pipe is flowing full, the hydraulic radius (R) is equal to the diameter divided by 4:

R = D/4 = 0.525 m / 4 = 0.13125 m

Now, we can calculate the flow rate using the slope of 1.0% (0.01 in decimal):

Q = (1/0.013) * 0.2165 m² * (0.13125 m)2/3 * (0.01)1/2

Finally, calculating the flow rate gives us:

Q ≈ 0.8787 m³/s (to four decimal places)

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