Explain the physicochemical changes that occur in soil due to sodicity and how that leads to soil degradation.

(Note: You can use clear diagrams, chemical formulae and relevant chemical equations)

describe three things a construction worker would have to read a paragraph or more?

3. Determine the available strength of two 3/8 in fillet welds that are loaded parallel to their length, are 10 inches long and are made from E70 electrodes. Determine the design strength by (a) LRFD and (b) ASD. [10.11- 25]

4. If the welds of the problem #3 above were loaded at their centroid and at 90 degrees to the weld length, determine the design strength by (a) LRFD and (b) ASD. [10.11- 29]

For three shapes of cross-section, A, B and C, such that the respective shape factors are k_A > k_B > k_C, identify which statement is true for moment capacity:

Select one:

Shape C is most efficient

Shape A is most efficient

None

All three shapes are equally efficient

Data from a field study on a step-aeration activated-sludge secondary are as follows:aeration tank volume = 120,000 ft3= 0.898 milliongalloninfluent wastewater BOD = 128 mg/Leffluent SS = 26 mg/Leffluent wastewater BOD = 22 mg/Leffluentwastewater flow = 3.67 mgdSS in waste sludge = 11,000 mg/LMLSS in aeration tank = 2350 mg/Lwaste sludge flow = 18,900 gpd = 0.0189 mgd return sludge flow = 1.27 mgd Using these data, calculate BOD loading and MLSS inaeration tank. Also, compute the sludgeage (solids retention time), aeration period, return sludge rate, BOD removal efficiency, and sludge production (in pounds of excess suspended solids per pound of BOD applied).

1. Why do you think the civil engineer should know about air pollution? Give specific examples from the viewpoints of transportation, building construction as well as environmental/public health engineering?

A 40 ft simple span beam is loaded with a uniform dead load of 2.4 kips/ft plus the beam self-weight and a uniform live load of 3.3 kips/ft. The lateral supports are located at the supports and at the midpoint of the span. Determine the leastweight W-shape to carry the load. Use A992 steel and Cb= 1.0. Design by (a) LRFD and (b) ASD. [6.16-36]

A 35 ft simply supported beam is loaded with concentrated loads 15 ft in from each support. On one end, the dead load is 8.0 kips and the live load is 18.0 kips. At the other end, the dead load is 4.0 kips and the live load is 9.0 kips. Include the self-weight of the beam in the design. Lateral supports are provided at the supports and the load points. Determine the least-weight W-shape to carry the load. Use A992 steel and Cb =1.0. Design by (a) LRFD and (b) ASD. [6.16-34]

1. Consider a 400-MW, 32 percent efficient coal-fired power plant that uses cooling water withdrawn from a nearby river (with an upstream flow of 10-m3/s and temperature 20 °C) to take care of waste heat. The heat content of the coal is 8,000 Btu/lb, the carbon content is 60% by mass, and the sulfur content is 2% by mass.

v. If the cooling water is only allowed to rise in temperature by 10 °C, what flow rate (in m3/s) from the stream would be required? Is this sustainable? What would you recommend?

vi. What would be the river temperature if all the waste heat was transferred to the river water assuming no heat losses during transfer? Would that be a problem? Why or why not.

vii. Estimate the hourly SO2 emissions (in kg/h) from the plant assuming that all the sulfur is oxidized to SO2 during combustion.

What are Intensity Duration Frequency (IDF Curves)?

what is their used for and why do they matter in the engineering world?

What are the primary strengths or weaknesses of the method or concept?

What would have made it easier for you to understand the method or concept?   

Consider a concrete beam in an interior environment as follows: a. The beam is simply supported with a design span of 4.8 metres. b. The dead load in the beam is uniformly distributed. c. Dead load on the beam, in addition to its own weight, is 6.9 KN/m of which 75% is permanent (long term). d. The beam carries a single concentrated live load at mid-span of 70 KN. e. 20% of the live load is considered short term. f. The dimensions of beam are: b = 280 mm, d = 490 mm, cover c = 45 mm g. The beam only has tension reinforcement provided by 3 N20’s. h. f’c = 25 MPa fy = 500 MPa γc = 24 KN/m3 Determine: 1. The design ultimate moment in the beam M*. 2. The ultimate moment capacity of the beam øMuo. Is the beam ductile? 3. The serviceability moment in the beam ?? ∗ . 4. The Code allowable mid-span deflection. 5. The long term deflection at mid-span of the beam. Does it comply with the Code requirements?

For the shape shown below, calculate the moment of inertia about the x axis. (Figure 8)The dimensions are d1=345 mm, d2=160 mm, d3=120 mm, and r=80 mm.

For the shape from Part C (shown again here for reference), calculate the moment of inertia about the y axis.(Figure 8)The dimensions

IN Bull Run, why was Judah sent to the battlefront? What challenges did he face?