1. One pump is not enough to pump water to a very high tank. If you use two pumps (to increase h), how are you going to install them?

(a) in parallel

(b) in series

2. For turbulent flow of all pipes, friction factor (f) depends on:

(a) Reynolds number (Re) only

(b) relative roughness (e/D) only

(c) both Re and e/D

4. For a pumping system, which tends to cause cavitation?

(a) placing the pump close to the source reservoir to minimize head loss

(b) setting the pump at a higher elevation relative to the reservoir water surface

5. Show the SI dimension and BG unit of specific energy (E)

Describe the method available for repairing cracked foundation walls.

Sound attenuation is an important in fabricating walls between rooms in luxury hotels. Three wall cavity fillers have been identified for use. The desired reduction in sound is based on the decibel level heard on the opposite side of a wall from the side where the sound intensity is at 88 decibels using the A weighting method. The sound heard in an adjoining room should be no more than 57 decibels. The science of sound is that sound is a wave with the magnitude of the sound measured as pressure (P). The formula for the decibel scale is 20*log(P/P_ref) where P_ref = 20 µPa. One µPa is equal to 10^-6 Pa.

a. What is the P of 88 decibels in pascals?    

b. What is the P of 57 decibels in pascals?     

For this problem, sound attenuation rating of material is measured by the fraction of sound pressure that penetrates through a layer of material thickness. A material rated as 0.75 per inch means the sound intensity pressure after passing through an inch of material is 75 percent of the starting value. Sound attenuation based on this measure is geometric so if there was 2 inches of material the resultant sound pressure intensity would be the rating squared or 0.75² of the starting pressure. When sizing the thickness to meet a specified sound reduction the practice is to round up to the next quarter of inch (0.25 inch) unit. If the calculated needed thickness was 1.64 inches the rounded up dimension would be 1.75 inches and all calculations and design sizing would use that dimension. Use the data on the materials located below to answer the questions.

c. What is the design thickness of Material A is required to meet the specification?   

d. What is the design thickness of Material B?

e. What is the design thickness of Material C?   

f. What is the cost per square foot of wall based on the thickness calculated above using the material that is the most expensive to install in a wall to meet the specification?   

g. What is the cost per square foot of wall based on the thickness calculated above using the material that is the least expensive to install in a wall to meet the specification?    

Q1) Design a concrete mix by using ACI Method of Mix Design having 28-day characteristic mean strength of 27 MPa for a deck of a residential building at Nebraska. Dry weather and gradually warming temperatures may be expected throughout the working week. Fresh concrete composed of a slump of 90 mm and maximum aggregate size of 25 mm. Determine the amount of water reducing admixture to be used for 0.24 % and 0.65 %. Deck is a flat surface capable of supporting weight, similar to a floor, but typically constructed outdoors, often elevated from the ground, and usually connected to a building. Decks that need piers or footings must have them installed below the frost line. This will keep the piers from heaving up out of the ground from the strength of the freeze. Reinforcing steel will help keep the piers from cracking. The freeze or frost line is the depth to which the soil freezes or has been known to freeze at some point in the past. It is absolutely critical that the foundations of buildings extend below this point in a soil profile. Except for a few arid locations, soils typically contain water and this water expands approximately nine percent in volume when it freezes. The frost line depth is not consistent around the nation because there

is such a dramatic difference in climate from state to state. Deck is composed of 2.5 cm reinforcement and there is no need for piers. The material properties are as follows:

For Coarse aggregate: SSD bulk specific gravity: 2.75, absorption capacity = 1.5 %, total moisture: 2.5 %, Dry-rodded unit weight: 1514 kg/m³.

For Fine aggregate: SSD bulk specific gravity: 2.65, absorption capacity = 1.0 %, surface moisture: 3 %, F.M: 2.6.

Cement: Type V, Sp.Gravity: 3.23

Probability constant: 1.22 and standard deviation: 2 MPa

A freeway is being designed for a location in mountainous terrain. The expected free-flow speed is 88.5 km/h. Lane widths will be 3.6 m and shoulder widths will be 1.8 m. During the peak hour, it is expected there will be a directional peak- hour volume of 2700 vehicles, 12% large tracks and buses and 6% recreational vehicles. The PHF and driver population adjustment are expected to be 0.88 and 0.90, respectively. If a level of service no worse than D is desired, determine the necessary number of lanes.

A 250 meter tall vertical concrete tower is exposed to horizontal wind load that deforms it 13 meter horizontally at the top. The statical system of the tower can be described as a vertical cantilever with constant uniform horizontal loading.The cross section of the tower is a quadratic box with constant size and thikcness throughout theheight of the tower, and due to the small construction site there is no room for a wider cross section. The tower has been reinforced with maximum allowed reinforcment, but the capacity in the bottom of the tower has been exceeded.

As a structural engineer you are told to find a way to change the design of the tower, to make it whitstand the current loading. What changes would you suggest?

NB. Prestressing is not an option.

A road includes dangerous geometric features for high speed travel which limit the travel speed on the highway in this area. Among alternatives, it is proposed to upgrade the road so that travel speed may be increased. The upgrade will cost initially $ 38,500,000 and the annual maintenance cost is 800,000 $. It will result in: 10 minutes reduction in travel time for the average running vehicle. The estimated time cost is $3.5/hr.  Decrease in the number of accidents by an average of 1.5 per day. The estimated average cost per accident is $ 5000.  Reduction in the average running cost per vehicle by $ 0.15 per day. For a project life of 30 years and money rate of 4%, what is economic feasibility of this project if the average daily traffic is 3500?

: A rectangular plate 1.5m wide and 2.5m deep is placed vertically in water so that the center of plate is 4m below the free surface. Determine the total pressure and the depth of center of pressure. State also whether the equilibrium is stable or unstable. The above rectangular plate is taken out of the water which weighs 350.5 N in air and 173.3 N in water of specific gravity 0.99. Find the volume and specific gravity of the plate. Draw a neat sketch

Common standard data: g = 9.80665 m/s²; the density of water: ϱH2O=1 kg/dm3ϱH2O=1 kg/dm3 exactly.

A box shaped pontoon with a(n) 24 m × 24 m square shaped base floats horizonatlly on a lake. The flat bottom of the pontoon is 160 cm below the water level.

• What is the weight of the pontoon?
  Find the vertical distance between the centre of buoyancy and the metacentre:
  
  Specify units

Construct an AoA network for the 'Project Infiltration', and explain how the activities,events and symbols are applied.

Identify and briefly different techniques which you have considered to use in order to draw the AoN network for 'Project Infiltration'.

Calculate the total duration of 'Project Infiltration'. Calculate the different forward and backward passes.

Calculate the float/slack of 'Project Infiltration'. Explain the critical path of 'Project Infiltration', and ensure that the reader understands the importance of the critical
path.

Using Matlab, create a code that determines the highest real root of f(x)=x3-6x2+11x-6.1 using the Newton-Raphson method with x0=3.5 for three iterations. Verify that the process is quadratically convergent.

I found the code to get the highest real root (root for three iterations = 3.0473), however, I do not know how to verify that it is quadratically convergent.

What could be the main sources of nitrogen contributing to river water quality deterioration?

Please select the reinforcement spacing for the entire span of a simply supported beam on a 22 ft span. Use the detailed method to calculate Vc. Do not use a shear envelope diagram use the regular shear force diagram. Use b = 16 in., d = 27 in., the main bending reinforcement consists of 4 #9 bars. The unfactored dead and live loads are 2.6 Kip/ft and 2.5 kip/ft, respectively, f’c = 4500 psi, and fy = 60,000 psi. Use #3 U stirrups. Also, locate in your beam the point beyond which no stirrups are required and find the distance from that point to the supports and to midspan. Use any allowable shear force reduction permitted by the ACI code. Provide a sketch of your final design.

Complete the bending design of a simply supported reinforced concrete beam with the following parameters: Service loads are W_D = 2.5 Kip/ft and W_L = 1.5 Kip/ft, Span = 16 ft, f'c = 6,000 psi, fy = 40,000 psi, b = 12 in., cover to the center of the steel = 3 in. Assume phi = 0.9, but make sure that phi is actually 0.9 at the end. Find h by doubling the recommended minimum height for this beam and provide it in whole inches rounded up to the nearest inch.

Design a rectangular footing for an 18-in square interior column with a dead load of 210 k and a live load of 180 k. Make the length of the long side equal to twice the width of the short side, fy = 60,000 psi, fc' = 4000 psi, normal weight, and qallowable= 3650 psf. Assume the base of the footing is 5 ft 0 in below-grade , γ concrete = 150 pcf and γ soil = 100 pcf. Also, assume h=24 in and cover = 4.5 in .

Answer the following questions :

a- Find the required area then the dimensions of the footing .

b- Check one way shear.

c- Check the punching shear.

d- Design the reinforcement in both directions .