Using the rational method, determine the amount of runoff that
would occur for a paved parking lot that is 100m * 50m and is
uniformly sloped from one long edge to the other long edge at a
rate of 2%. The time of concentration for this parking is 4
minutes. The five-year storm with duration of 4 minutes has an
intensity of 10 mm/hr. The runoff coefficient for this parking lot
is 0.80.آ [Q=0.166 CIA]
The runoff from part (a) is to be contained in a trapezoidal
drainage ditch with the following properties: side slope = 2m
horizontal run for every 1 m rise, width of invert = 2m,
longitudinal slope = 0.005 m/m, and Manning's number = 0.08. If the
maximum permittedآ depth of water is 100 mm, using Manning's
equation for open channel flow, determine if the ditch will be able
to accommodate the flow in part a
In: Civil Engineering
In: Civil Engineering
You are planning to excavate the 30-foot by 40-foot basement area of a house to a depth of 10- feet in common earth. An 18-inch wide, 5-foot deep, 100-foot long sewer trench will also be required. You have at your disposal a hydraulic excavator with a ½ cubic yard 24-inch wide bucket. The excavator’s maximum digging depth is 14.7-feet and the average angle of swing is estimated to be 75-degrees. Job efficiency is expected to be 45-minutes per hour with costs for the excavator being $50 per operating hour and $250 each to transport the excavator to the site and return it to the equipment yard after trench and basement excavations are complete. Allow for 5-percent overage in basement excavations and 10-percent overage beyond the capabilities of the equipment for the trench. After the foundation has been placed and backfilled, and the trench has been covered, it is estimated that 400 cubic yards of loose material will remain in a single stockpile that will need to be moved offsite. You will have at your disposal a crawler crane with a 0.90 LCY clamshell to load a series of dump trucks. Cycle time for the clamshell is estimated to be 45-seconds with the same 45-minute per hour efficiency. Costs for the crane and clamshell are $75 per operating hour and a combined lump sum of $500 to mobilize and demobilized.
ASSUMPTION(S)/CONDITION(S) Excavator bucket heap accounts for material swell. You do not need to account for swell and/or shrinkage in your calculations.
When using tables to determine appropriate factors to use in your calculation and a range is given, use the middle value between the high and low.
All material excavated for the trench will be used during backfilling operations. There are no spoils remaining from the trench portion of the excavation.
Assume that sufficient dump trucks will be available into which to load the remaining basement spoils. That is, there will be no downtime waiting for trucks to become available.
No partial workdays are allowed. Should less than a full day be required to all or a portion of the work, payment for the full 8-hours is still required.
QUESTION 1 How much material is required to be excavated from: a) The basement, and b) The trench?
QUESTION 2 What is the time required to excavate a) the basement, and b) the trench?
QUESTION 3 What are the total costs and unit costs to excavate: a) The basement, and b) The trench?
QUESTION 4 How many hours does it take to load the remaining excavation spoils to transport them off-site?
QUESTION 5 How much does it cost to mobilize, demobilize, and load the excavation spoils in total and as a unit cost?
In: Civil Engineering
2. A simply supported rectangular concrete beam is to be made from M21 concrete grade and reinforced with steel bar of 345 MPa yield strength. It carries a uniformly distributed load of 12.5 kN/m and has a span of 6 m. Design the beam, assuming that the shape factor is 0.4. The weight density of steel is 77 kN/m3 and that of concrete is 24 kN/m3.
In: Civil Engineering
In: Civil Engineering
1. A soil has Horton infiltration parameters f0 = 110 mm/h, fc = 20 mm/h, and k = 1.8 h−1.
a. Compute the total infiltration and runoff from a storm with an intensity of 15 mm/h and a duration of 2 hours.
b. Suppose the intensity is i = 90 mm/h. One of your group members (not you) computes the ponding time t by setting the infiltration capacity to the intensity and solving for t; that is, your teammate obtained t from the Horton equation. Explain why this approach is wrong.
c. Compute the total infiltration and runoff from a storm with an intensity of 90 mm/h and a duration of 2 hours.
d. A bumbling, but observant professor, computed a total infiltration of about 98 mm for part d. Why did she question this result?
In: Civil Engineering
Abrams established a rule that relates the water-cement ratio to strength of concrete. List two additional factors that have a significant influnce on the concrete strength.
Q2. Explain does why: • The transtion zone impact more rich cementitious mixtures than lean ones.
• Air entrainment reduce the strength of moderate to high strength concrete yet may enhance the strength of low strength concrete.
• ASTM cements Type I. III, and V have different impact on early and later strength of concretes made with these cements.
• On the basis of qual workability the surface characteristics of aggregate have a limited impact on the ultimate strength of concrete.
• the surface characteristics of aggregate have a clear impact on ultimate strength of concrete on the basis of qual water content.
• The cylinder strength is higher than that of cube's.
• The aspect ratio of concrete cylinders has no impact on compressive strength obtained in compression testing machine with brush platens.
• Concrete bridges should not be subjected to stress levels higher than 0.55 of ultimate strengths.
• the maximum aggregate size of aggregate have two opposing effects on concrete strength.
In: Civil Engineering
a. Interstitial atoms belong to line defects, yes or no?
b. What is the influence of crystallinity increase on polymer modulus?
c. Why are polymers lighter than metals and ceramics? Two reasons.
d. How can glass fiber be made (name 2 methods/procedures)?
f. What are the three limitations of ferrous alloys, generally?
g. Why poly crystals are stronger than single crystals?
h. Can polymers be purely crystalline? Yes/No
i. What are the three functions of screen pack in polymer extruding?
In: Civil Engineering
Determine if a real-world system could be represented as a rigid body
I just need an exemple
In: Civil Engineering
In AutoCAD, ILLUSTRATE how the following command prompts can be performed and INDICATE when it is necessary to perform EACH command prompt. Note that all steps are very important and must be mentioned. (i) EXPLODE (ii) LAYERS (iii) HATCH (iv) TRIM AND EXTEND (v) BREAK (vi) CALIBRATING PAPER SIZE (vii) FILLET (viii) CREATING TABLE (ix) OFFSET
In: Civil Engineering
The following data is given for a horizontal highway
curve having 2 lanes with Lane width of 3.65 m each: Ruling design
speed is 110kmph, Allowable rate of change of circular acceleration
= 0.5 to 0.8. Allowable rate of introduction of super-elevation = 1
in 144, Take maximum allowable superelevation and lateral
frictional co-efficient is 0.15.
Calculate the length of a transition curve for following cases.
Rate of change of centrifugal acceleration
(C).
Rate of introduction of super-elevation.
Using empirical equations for plain and mountainous
terrain.
In: Civil Engineering
j. What is the difference between thermoset and thermoplastics when both are heated repeatedly?
k. Impurity in metals and semiconductors both increase resistivity, yes or no?
l. Is plastic strain recoverable? Why?
m. What are the liquid ink-based 3d printing? (at least 2 methods)
In: Civil Engineering
In: Civil Engineering
Hydraulics & Hydrology
Problem Statement
The Romans were exquisite water engineers, and that without having at their disposal the modern tools and the knowledge we have today. Remember that Hydraulics and Hydrology as we know it now only came to be in the 1700’ when engineers started to put a fundamental framework together that is/was based on lab experiments and theoretical approaches and principles. Until then, you just “knew”. The Romans build all sorts of hydraulic systems, from irrigation canals, to water supply infrastructure, to the famed “hot baths” of Rome, to sewer systems, you name it. They realized that if you want water for different purposes at locations that were important to you that very often you had to get the water there because it just was not available in close proximity.
One of the marvelous feats they accomplished was to build water supply systems that would run over dozens of miles to convey water from sources to locations of need, typically the towns and cities they founded in their vast empire. They managed to do so by building a lot of infrastructure that withstood time and that, almost 2000 years later, is still in place for us to marvel at. Especially the many bridges that were built to cross valleys and gorges to keep the supply line flowing as an open channel are spectacular in their construction, such as the Pont du Gard, Segovia, and Aquila aqueducts.
Task:
In: Civil Engineering
Part III – Short Essay (please limit your answer to 250 words)
Please describe how the following elements of project planning are combined to generate a base project plan projecting estimated project cost over time.
- Work breakdown structure
- Organizational breakdown structure
- Control accounts
- Project schedule network
- Project cost estimate
- Cost- and time-weighted schedule
In: Civil Engineering