A -3.4% grade intersects a 4.2% grade at STA 5+180 at an elevation of 125.98. A vertical curve of length 120m is to be run forward from the point of intersection, and a curve of length 80m is to be extended back forming an unsymmetrical curve.
a.)Determine the elevation of the lowest point.
b.)Determine the elevation of the second quarter point on the curve.
In: Civil Engineering
Use diagram to explain the layout of domestic (cold) water system from the underground main pipe to the inspection chamber (manhole). Label all piping and fittings.
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Describe laboratory and geophysical methods to measure intact rock strength. Explain why measurements of rock strength alone are insufficient to assess the difficulty of excavation and the likely stability of the rock mass during and after construction.
In: Civil Engineering
please paraphrase and don't use paraphrasing tool
please please make you work readable.
The primary cause of "plastic shrinkage" cracks is the
rapid evaporation of water from the surface of the concrete.
Immediately after the concrete has been placed, the particles
within the concrete begin to settle. When the particles settle, the
water within the concrete displaces and rises to the top. This
process is better known as "bleeding." Not all of the water within
the concrete displaces. Under most weather conditions, some of the
water on the surface of the concrete evaporates. The rate of
evaporation depends on factors such as the temperature of the
concrete, temperature of the air, relative humidity, and wind
velocity surrounding the concrete. Table 1 shows how different
weather conditions and properties effect the rate of evaporation.
The highest evaporation rates are obtained when the concrete and
air temperatures are high, when the relative humidity of the air is
low, when the concrete temperature is high compared to the air
temperature, and when a strong wind is blowing over the surface of
the concrete. The rapid evaporation of water at the surface is most
associated with placing concrete in hot weather conditions.
However, plastic shrinkage cracks can also form in cold weather
conditions when the temperature of the concrete is high compared
with the surrounding air temperature. When the temperature at the
surface creates an evaporation rate that exceeds the rate of water
produced by the bleeding process, the water film disappears and the
top surface of the concrete begins to shrink. When the evaporation
rate exceeds1.0 kilogram per square meter per hour, it is almost
certain that plastic shrinkage cracks will develop (Figure 1). When
the evaporation rate is greater than 0.5 kilogram per square meter
per hour cracking is possible.
Plastic shrinkage cracks typically occur on horizontal
surfaces exposed to the atmosphere. These cracks are different from
other early cracks because they are deeper and wider. Plastic
shrinkage cracks are typically two to four inches deep and
approximately one-eighth inch wid.
If you want you can SUMMARIZE in another words as well Sir
In: Civil Engineering
for certain rainfall data, the standard deviation Sx = 3.4 mm. If the Normal distribution was used and the 10 year rain x10 = 34.1 mm, then the 2 year rain x2 is:
6.82 mm
29.74 mm
31.72 mm
38.18 mm
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Outline the operational principles, relative advantages and disadvantages of the range of drilling methods for sampling unconsolidated material, solid rock and marine sediments.
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The geology of a proposed major industrial site is thought to consist of a thin layer (1-5m) of unconsolidated sandy material overlying dolerite bedrock. The dolerite is known to have a very irregular upper surface and maybe highly weathered in places. Describe geophysical investigation techniques that may be suitable for mapping the thickness of the unconsolidated sand and also the distribution of unweathered basalt at shallow depths. For each method you recommend, outline: a) the basic physical principles of the technique, b) the expected outcomes of the survey.
In: Civil Engineering
Describe the characteristics of drilling methods that are commonly used for geotechnical assessments on land and in marine environments. In your answer you should describe: a) the drilling process, b) the materials that can be drilled, b) the nature of the sample that is retrieved, c) the typical depth of investigation, d) the relative merits of each technique that you recommend.
In: Civil Engineering
i Calculate the minimum DO level and its distance in miles downstream using the oxygen sag equation. Assume k1 = 0.046 per day and k2 = 0.304 per day. The saturation DO = 8.5mg/l. (1 mile = 5280ft)
ii At what distance downstream would the DO level of the river be equal to 6.10 mg/l?
iii How much should the wastewater DO be increased to maintain a minimum DO of 4.8mg/l anywhere along the river. Assuming that the BOD of the wastewater and the river flow remains the same?
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Discuss ( decentralized natural water treatment plant in an urban setting in Oman).
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A rectangular channel of bottom width B = 7 m carries an average discharge of Q = 8 m3/s. There are two successive long reaches. The first reach has s01=0.015 and n1=0.010; and the second reach has s02=0.0017 and n2=0.021. Classify the slopes.
In: Civil Engineering
a) Explain differential movement and prevention in brick and concrete masonry. Where the control joints are must be located.
b) A 150 –ft exterior clay brick wall is designed for ½ -in expansion joints and a joint compressibility of 40 %. Determine the maximum joint spacing and the minimum number of joints required for entire wall. (Wall is going to be built in Lubbock TX. Temperature difference can be taken as 80ºF. Annual mean relative humidity is moderate 75>AMRH>50)
In: Civil Engineering
An ascending grade of 4% and a descending grade of 2% intersect at STA 12+598 whose elevation is at 518.99m. The two grades are to be connected by a parabolic curve, 160 long. Find the elevation of the first quarter point on the tangent and the summit of the curve.
a.)Determine the elevation of the summit.
b.)Determine the station of the summit.
c.)Determine the elevation of the first quarter point on the tangent.
d.)Determine the elevation of the midpoint on the curve.
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Please type your answer and make it too short answer just type it.
1- When do I need to check for deflections in a reinforced concrete member?
2- What is the difference between short term and long term deflections?
3- How does ACI estimate the long term deflections in a member?
In: Civil Engineering