Consider a wall with the following dimensions: 120 feet long x 15 feet high x 9 inches thick. Also consider using a concrete pump with a capacity of 800 cubic feet per hour. Concrete mix consists of Type 1 concrete with retarder, and a unit weigh of 155 pcf. The maximum pressure applied on the wall form is approximately 2,200 psf.

What is the rate of pour?

What is the maximum temperature at which the concrete can be poured? Clearly label the units of temperature, and state all justifications for selecting equations, and coefficients accordingly.

What all factors an engineer must consider for designing a retaining wall to retain a soil of height 10m? How those factors are different for a cohesionless soil, a cohesive soil and a saturated soil?

A vertical curve has its PVI at station 14+75.00 and elevation 76.29 ft. The grade of the back tangent is 3.4%, the grade of the forward tangent is -4.8%, and the curve length is 450 ft.

1. Determine the stations and elevations of the BVC and EVC.
2. Determine the location and elevation of the high point of the curve.
3. Determine the curve elevation at station 14+00 and station 16+00.

Q4: Experiments were conducted to determine the safe buckling load on columns with T-section
100 mm × 100 mm × 10 mm with different support conditions. When both ends of the columns
are fixed, safe crippling load carried by the column was found to be 60 × 103 N. Suggest the
length for other three columns for the same crippling load when the support conditions are
changed to one end fixed but the other end free, both the ends hinged and one end fixed but the
other end hinged. The cross section of the column is kept constant in all cases, and E = 200 GPa.
Take factor of safety = 4.
Instead of T section, a hollow column of same material having length 5 m and external diameter of
55 mm when subjected to a compressive load of 60 kN, there was a shortening in the length of the
column by 0.120 cm. Suggest a suitable value for the thickness of the column to withstand the safe
crippling load when one end of the column is fixed and other end is free? (8 m

3-lane freeway reduces to 2 lanes

total flow in section = 5000 veh/hr

lane saturation flow rate= 2400 veh/hr

traffic density at A: 10veh/km/ln

shockwabe speed Wab between A nad B = -10km/hr

Find traffic density at B (immediately upstream of the lane reduction) and the stream flows at locations A (far upstream from lane reduction), B, and C (within the lane reduction)

A six-lane freeway with three lanes in each direction is on a level terrain and has 11-ft

lanes with a 4-ft right-side shoulder. The total ramp density is 2 ramps per mile. The

directional peak-hour traffic volume is 5400 vehicles with a peak-hour factor of 0.95 and

all familiar users. The traffic stream includes 5% trucks and another 5% buses and no

recreational vehicles. The city has decided to ban all heavy vehicles from using the

freeway during the peak hour. Compute the level of service before and after the heavy

vehicle ban.

Briefly describe the meaning of the following glulam designations:

a. Stress Class 20F-1.5E
b. Stress Class 24F-1.8E
c. Stress Class 30F-2.1E SP

d. Combination 20F-V7 DF/DF

e. Combination 24F-V5 DF/HF

f. Combination 24F-E11 HF/HF

g. Combination 26F-V2 SP/SP

h. Combination 5 DF

i. Combination 16 HF j. Combination 48 SP

The total flow at a wastewater treatment plant is 682 m3/day. The purpose of the plant is to remove compound Z from the wastewater by treating it in reactors, using a newly developed microbial process. Assume the microbial treatment can be modeled as a first order reaction with a rate coefficient of 0.36/h. Suppose the flow is split evenly and treated in two parallel reactors– one complete mix and one plug flow -- each with a volume of 88 x 103 L. The effluent from the two reactors are then combined and discharged from the plant. If the influent concentration of Z is 139 mg/L, what is the steady state effluent concentration from the treatment plant?

Question 610 pts

A BOD test is run using 10 mL of treated wastewater. Chemicals to inhibit nitrification were added. The initial dissolved oxygen (DO) in the bottle is 9.5 mg/L and after 5 days, the DO is 5.0 mg/L. For the bottles that were allowed to run for 20 days, the DO is 4.0 mg/L. A similar test was done where nitrification was not inhibited. The initial DO was the same and the DO after 20 days was 3.0 mg/L. What is the BOD₅, ultimate BOD (BOD_u)  and the nitrogenous NBOD. BOD bottle volume is 300 mL.

B O D ( m g L ) = D 1 − D 2 ( m g L ) P

D1 = DO in bottle immediately after preparation

D2 = DO in sample after t days

P = fraction of sample volume to total volume

Group of answer choices

135, 165 and 195 mg/L

13.5, 16.5 and 19.5 mg/L

10.8, 43.8 and 33 mg/L

1350, 438 and 1080 mg/L

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Question 710 pts

You carried out solids analysis of a sample collected from an industrial site. The data is as follows:

Weight of crucible = 42.4523 g

Volume of sample = 25 mL

The weight of the crucible and dry solids after drying at 105°C = 42.4986 g

Weight of crucible and residue after burning off at 550°C = 42.4863 g

The total solids, volatile solids and fixed solids are

Group of answer choices

926, 246 and 680 mg/L, respectively

926, 680 and 246 mg/L, respectively

105.2, 56.0 and 49.2 mg/L, respectively

1052, 560 and 492 mg/L, respectively

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Question 85 pts

A wastewater sample was collected from a treatment plant and sent for quality analysis. The BOD test was carried out over 20 days. No chemicals to inhibit nitrification were added. The BOD value in this case is a measure of the concentration of ___________ in the wastewater

Group of answer choices

almost all carbonaceous and nitrogenous compounds

all organic and inorganic compounds present in the wastewater

particulate organic carbonaceous and nitrogenous compounds

almost all dissolved nitrogenous organic compounds

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Question 95 pts

During the_____________ phase, the number of microorganisms (in the BOD bottle) is more than during the _______________phase, but the rate of production is lower

Group of answer choices

declining growth, log growth

log growth, declining growth

declining growth, endogenous respiration

log growth, endogenous respiration

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Question 105 pts

Aerobic autotrophic bacteria

Group of answer choices

Get their energy from oxidation of inorganic compounds, e.g. NH₄, carbon from CO₂ and O₂ from air (or mixers)

Get their energy from oxidation of inorganic compounds, e.g. NH_4, carbon from CO₂ and do not need O₂

Get their energy from the sun (i.e. photosynthesis reactions) and carbon from CO₂

Get their en

Q1: Analysis of forces and moments were done for a simply supported beam having span 10 m
carrying a uniformly distributed load of ‘w’ kN/m over a length of 5 m from the left end support
and point loads ‘2w’ kN, ‘3w’ kN and ‘1.5w’ kN at distances of 6 m, 7 m and 8 m respectively from
the left end support. It was observed that the maximum bending moment acting on the beam is
equal to 192 kNm. Suggest a suitable value for ‘w’ based on this loading condition. How it will
change the reactions at the supports? What happens to the shear force and bending moment
values at the supports and at the points where loads acting? By plotting the bending moment and
shear force diagram for the beam, briefly conclude the relationship between the values for shear
force and bending moment.

An axial pull of 45 kN is applied on the three bars of varying cross section and connected to
each other as shown in figure. Two outer steel bars are of same length and diameter, but the
middle bar made up of brass having cross sectional dimensions 20 mm x 20 mm. The length of the
middle bar used was 4 times more than that of the two outer bars and stress in the two outer
portion were found to be 175 N/ mm2 causing a total elongation of 13.25 mm. Consider the values
for modulus of elasticity of steel equal to 205 x 105 N/cm2 and the modulus of elasticity for brass
equal to 88 x 105 N/cm2. Recommend a suitable value for the diameter of the two outer bars and
length of all three sections based on the given data.
If all three bars are made up of steel having modulus of elasticity 98 kN/mm2 and shear modulus
410 tonnes/cm2, what will be the values for the lateral dimensions of all three bars? Verify the
relationship between lateral strain and longitudinal strain based on the findings.