Q2. A flexible pavement is to be designed based on AASHTO method. The following are the characteristics of this pavement: R = 90%, S0 = 0.40, Pi = 4.5, Pt = 2.0, SN = 3.5 and Mr (subgrade) = 15,000 psi. (a) If it was decided to use to a base course and an asphalt layer, what will be the thickness of each if you know that the sub-grade CBR = 8, base course CBR = 85, m = 1.0, surface modulus of elasticity = 400,000 psi. (b) How many years this pavement will approximately last, knowing that the average ESAL per year during the design period is 530 000 repetitions.
In: Civil Engineering
Q2. A flexible pavement is to be designed based on AASHTO method. The following are the characteristics of this pavement: R = 90%, S0 = 0.40, Pi = 4.5, Pt = 2.0, SN = 3.5 and Mr (subgrade) = 15,000 psi. (a) If it was decided to use to a base course and an asphalt layer, what will be the thickness of each if you know that the sub-grade CBR = 8, base course CBR = 85, m = 1.0, surface modulus of elasticity = 400,000 psi. (b) How many years this pavement will approximately last, knowing that the average ESAL per year during the design period is 530 000 repetitions.
In: Civil Engineering
A car is traveling up a 1.5% grade at 65 mi/hr on good, wet pavement. The driver brakes to try to avoid hitting a cone on the road that is 300 ft ahead. The driver’s reaction time is 1.5 second. When the driver first applies the brakes, a software flaw causes the braking efficiency to lower to 0.8 for 100 ft. After the initial 100 ft, the braking efficiency returns to 1.0. How fast will the driver be going when the cone on the road is hit if the coefficient of rolling resistance is constant at 0.015? (Assume minimum theoretical stopping distance and ignore aerodynamic resistance.)
In: Civil Engineering
a.For a single severe rainfall event, what are the four components or fates at the start of the hydrologic cycle? Which two capture the most rain or snow at the early stages of the event, and what happens to it?
b. A storm td = 2 hrs. Rain intensity is steady i = 1.0”/hr. The infiltration rate quickly stabilizes at f= 0.25”/hr. How many inches infiltrate over 2 hours?
c. List the benefits of directing roof runoff to an infiltration bed, and also, the risks. Why would a surface infiltration bed probably perform longer than an underground one?
In: Civil Engineering
simply supported T-beam of 6 m clear span carries an
ultimate load of 38 kN/m. The beam section dimensions, support
particulars and tension reinforcement are shown in Figure
Q1.
Design the shear reinforcement for the beam.
Data Given:
The characteristic strength of the concrete is
25
N/mm2.
The characteristic strength of steel reinforcement is
460N/mm2.
The characteristic strength of shear reinforcement is
250N/mm2.
Nominal maximum aggregate size (hagg) is
20
mm
Diameter of shear links is
8 mm
Exposure condition is
mild
Minimum required fire resistance is 1.0
hour
In: Civil Engineering
Please show all work and formula:
Please use the information on the table below to answer this question.
Security Actual Return Beta
A 12% 1.2
B 10% 1.0
C 14% 1.4
In: Finance
The city is considering 2 separate cell tower providers. The city expects a benefit-cost ratio of 1.0 or better, and their cost of capital is 10% per year. Assume repeatability
| Verizon | AT&T | |
| Initial investment | $90,000 | $170,000 |
| Useful life in years | 6 | 12 |
| Market value at end of useful life | $25,000 | $40,500 |
| Annual benefits from operation | $30,000 | $40,000 |
| Annual operating expenses | $9,800 | $11,300 |
a) Conduct benefit-cost ratio on the Verizon and AT&T projects and indicate which project is the preferred project (Show Work)
b) Conduct an incremental difference to validate the decision.
In: Economics
A 2-in-ID wetted wall column is being used to strip CO2 from an aqueous solution by an air stream at 1.0 m/s. At one point in the column, the concentration of CO2 in the air stream is 1.5 mole percent. At the same point in the column, the concentration of CO2 in the water is 0.5 mole percent. Determine the gas-mass-transfer coefficient kG (kg mole/atm-m2-s) and the mass flux at the point in the column. The column is operated at 10 atm and 25°C. The Henry’s constant of CO2 in water at 25°C is 1.64 × 103 atm/mole fraction CO2 in solution.
In: Other
A hydroelectric power station is required to generate a total of 4.2 MW from a number of single-jet Pelton wheel turbines each operating at the same rotational speed of 650 rpm, at the same power output and at a power specific speed of 1.0 rev. The nozzle efficiency ηN of each turbine can be assumed to be 0.98, the overall efficiency ηo is assumed to be 0.88, and the blades speed to jet speed ratio v is to be 0.47. If the effective head HE at the entry to the nozzles is 250 m, determine:
In: Mechanical Engineering
The sequence of a polypeptide X is as follows:
THCARKEDSGYPEWANVRDECW
1. The Optical Density (O.D.) at 280 nm of a solution of the above
polypeptide X is 0.51 at the standard experimental conditions (i.e.
optical length L = 1.0 cm) . What is the concentration of the
polypeptide X in this solution (in mM)? (The molar absorptivity (e)
for tyrosine and tryptophan residues at 280 nm are 1,400
M^(-1)cm^(-1) and 5,500 M^(-1)cm^(-1), respectively).
2. Estimate the molecular weight of this peptide.
3. Draw side-chain structures and peptide bonds for the first five
amino acid residues of the polypeptide X.
In: Chemistry