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2 years ago

8

an existing highway-railway at-grade crossing is being redesigned as grade separated to improve traffic operations. The railway

must remain at the same elevation. The highway is being reconstructed to travel under the railway. The underpass will be a sag curve that has an initial grade of -2% and a final grade of 2%. The PVI of the sag curve will be centered under the railway (a symmetrical alignment). The sag curve design speed is 45 mi/h. How many feet below the railway should the curve PVI be located

1 answer:

Gekata [30.6K]2 years ago

7 0

Answer:

Please find attached solution

Explanation:

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Furkat [3]

To solve this problem it is necessary to apply the concepts related to the heat exchange of a body.

By definition heat exchange in terms of mass flow can be expressed as

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From our equation we have that

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$W = \dot{m}c_p (T_2-T_1)$

Rearrange to find $T_2$

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Replacing

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A wastewater treatment plant discharges 1.0 m3/s of effluent having an ultimate BOD of 40.0 mg/ L into a stream flowingat 10.0 m

kondaur [170]

Answer:

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b) 5.6 mg/l

Explanation:

Given data:

effluent Discharge Q_w = 1.0 m^3.s

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Discharge of stream Q_r = 10 m^3.s

Stream ultimate BOD L_r = 3 mg/l

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$L_t = L_o e^{-kt}$

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Answer:

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