The pressure drop per unit length of a pipe, dl/dp , for steady, incompressible viscous flow through a straight horizontal pipe depends on the average velocity, V, density of fluid, p, fluid viscosity, µ, pipe diameter, D, and the roughness height, ks. Determine the dimensionless groups that can be used to correlate the data.

Annual emissions of CO₂, CH₄ and N₂O in the USA are estimated to be 6,000 MtCO₂/yr, 36 MtCH₄/yr and 1.75 MtN₂O/yr.

1. What are the impacts of these gases emitted from the USA over a 100-year time horizon?
2. Find the total equivalent CO₂ emissions.

For bending only, determine the lightest-weight W-shape
to carry a uniform dead load of 4.5 kip/ft plus the
beam self-weight and a live load of 3.5 kip/ft on a simple
span of 24 ft. Consider only the limit state of yielding and
use A992 steel. Design by (a) LRFD

At the end of a sporting event, vehicles begin leaving a parking lot at λ(t) = 12 − 0.25t and vehicles are processed at μ(t) = 2.5 + 0.5t [t is in minutes and λ(t) and μ(t) are in vehicles per minute]. Assuming D/D/1 queuing, determine the total vehicle delay, longest queue, and the wait time of the 50th vehicle to arrive assuming first-in-first-out and D/D/1 queuing.

Answer:  total delay=1016.15 veh-min, Delay 50th veh=5.64 min, Max Q=60.167 veh

What do you believe is a reasonable availability or utilization rate (the percentage of your time that is charged to billable projects) is for a staff engineer one month after the engineer starts working for the company after just graduating from college?

1. 6 Months?
2. 1 Year?
3. Explain the reasoning for your responses

A factory disposes 1.1 m³/s of treated industrial wastewater into a river. The wastewater has an ultimate biochemical oxygen demand of 25 mg/L and dissolved oxygen of 2 mg/L. Just upstream of the wastewater outfall, the river has a flow rate of 10 m³/s, ultimate biochemical oxygen demand of 6 mg/L, and oxygen deficit of 2 mg/L. At the river temperature, the saturation concentration of dissolved oxygen is 9 mg/L. The deoxygenation coefficient is 0.19 d^-1 and reaeration coefficient is 0.11 d^-1. The velocity of the river is 0.4 m/s.

(a) What is the ultimate biochemical oxygen demand (mg/l) immediately downstream of the outfall?

(b) What is the dissolved oxygen (mg/L) immediately downstream of the outfall?

(c) What is the oxygen deficit (mg/L) 97 km downstream of the discharge point?

(d) What is the maximum oxygen deficit (mg/l) along the river, and where does it occur (km)?

A rectangular beam of base b = 50 mm and height h = 25 mm is bent into a curved beam of 100 mm radius (R), and is subjected to a bending moment M of 500 N-m. Determine: The largest tensile and compressive stresses, how do the above values compare with the ones for straight beam?

5. Name the two types of fatigue cracking and the critical pavement locations.

Type:                              Critical location:    

Type:                                Critical location:

6. Name the causes typically associated with both types of fatigue cracking.

First Type:                             Causes:

Second Type:                         Causes:          

7. Name the type of loading typically used in the laboratory for evaluating:

Thin pavements        :          

Thick pavements       :          

8. In a typical conventional asphalt concrete pavement, keeping all other factors constant, (FILL IN THE BLANKS)

1. Increasing the HMA thickness typically                        fatigue cracking.

2. Increasing the HMA modulus typically                         fatigue cracking.

3. Increasing the wheel load typically                                fatigue cracking.

4. Increasing the tire pressure typically                             fatigue cracking.

17. List three computer programs that may be used to calculate pavement responses in flexible pavements.

18. In terms of fatigue cracking, a damage index, D, of 1.0 means that the roadway

19. List the three types of distortion.

20. __   ___           and __ _     __ are two mechanisms that cause rutting.

The head loss of a water of kinematic viscosity 1x10^-6 m^2/s in a 50mm diameter pipeline was 0.25m over a length

of 10 m at a discaherge of 2L/s. What is the corresponding discharge and hydraulic gradient when oil of kinematic viscosity 8.5x10^-6 m2/s flows through a 250mm diameter pipeline of the same relative roughness.

Water has total hardness of 155 mg/L as CaCO₃ and contains 0.004 M HCO₃^- at pH 7. What is the carbonate hardness and non-carbonate hardness in mg/L as CaCO₃? Would you use lime softening or lime-soda softening for this water and why?

“The Valuer is a reflector of markets and not the maker of market” Critically discuss the above statement.