Using the column interaction diagrams in Appendix A (Concrete strength = 5 ksi, steel reinforcement yield strength= 60 ksi,) with longitudinal reinforcement ration of approximately 2%, design square columns with equal reinforcement on all sides to carry each of the following loads and select the longitudinal and transverse reinforcement: 1. Pu = 2000 kips and Mu = 160 ft.kips 2. Pu = 1000 kips and Mu = 220 ft.kips 3. Pu = 500 kips and Mu = 160 ft.kips
In: Civil Engineering
You are required to perform a comparative RC short column design study according to ACI 318-19 using the following information: service dead load = 800 kips, service live load = 600 kips, concrete strength = 5 ksi, steel reinforcement yield strength= 60 ksi.
1. Design a rectangular tied column the can support the given loads safely and adequately. The column width is 25 inches. Sketch reinforcement in cross-section.
2. Design a circular tied column the can support the given load safely and adequately. Sketch reinforcement in cross-section.
In: Civil Engineering
In: Civil Engineering
In: Civil Engineering
In: Civil Engineering
The rate of heat transfer, Q [energy/time = power] through a pipe wall between a fluid and the surroundings depends on fluid properties: density (ρ), viscosity (μ), specific heat (cp [energy/temperature/mass]); and also on pipe and flow properties: the length (l), diameter (D), and thermal conductivity (λ [power/length/temperature]) of the pipe, fluid mean velocity (V), and the temperature difference (ΔT) between the pipe wall and the surroundings. Use dimensional analysis to express this system in terms of dimensionless numbers. The Π group that includes Q˙ should be expressed as a function of the other Π groups.
In: Civil Engineering
When confronted with a discrepancy in the plans and specifications, what form do you use to get an answer from the architect?
1- Submittal
2- AIA Form 101
3- RFI
4- RFP
In: Civil Engineering
Given the following excess rainfall hyetograph and 1-hr unit hydrograph, what would the 5th ordinate of the storm hydrograph be in cfs? Pn (intervals of 1 hr) = [0.2, 0.4 ,0.5 ,0.2 ,0 ,0.1] in UH (intervals of 1 hr) = [0, 100, 320, 450, 370, 250, 160, 90, 40, 0] cfs
In: Civil Engineering
Perform an ACI mix design using the following data (make assumptions as needed)
The 28-day compressive strength should be 4,000 psi. The concrete is to be used under exterior condition subject to deicer.
The slump should be between 3 and 4 in. and the maximum aggregate size should not exceed 1 in.
The coarse and fine aggregates in the storage bins are wet.
The properties of the materials are as follows:
Cement- Type I, specific gravity = 3.15
Coarse Aggregate:
Bulk specific gravity (SSD) = 2.70; absorption capacity = 1.1%; dry-rodded unit weight = 105 lb./ft.3
Moisture content = 2.1%
Fine Aggregate:
Bulk specific gravity (SSD) = 2.67; absorption capacity = 1.3%; fineness modulus = 2.70;
Moisture content = 2.8%
In: Civil Engineering
1. On one approach of an intersection with fixed time traffic signal, vehicles arrival rate is 600 vehicles per hour. The effective green time for this approach is 30 seconds, the saturation flow of this approach is 1800 vehicles per hour and the cycle time of the intersection is 80 seconds.
a. Evaluate the performance of the signal design i.e. will all vehicles clear during the green time?
b. Recommend the changes to the green time for this approach to achieve an optimum signal design i.e. If there is surplus green time, then state its value.
c. Due to a traffic incident, the original saturation flow is reduced by 20%. Will there be any delay under the new situation based on the original design? How many vehicles will experience the delay?
d. Under a new strategic transport plan to divert some vehicles to other areas, the saturation flow has been reduced to 1300 vehicles per hour by reconfiguring the layout of the intersection. Under this condition how may vehicles will be delayed in each cycle?
In: Civil Engineering
how does the annual temperature range depend on latitude?
why does the annual temperature range depend on latitude?
In: Civil Engineering
1-S0 in an activated sludge process represents
_________________________ concentration.
2-X in an activated sludge process represents
___________________________ concentration.
3-Biomass present in the influent is a product of biomass
concentration in the influent multiplied by ______________
___________.
4-Hydraulic detention time is a ratio of ______________ and
_________________.
5- ___________________ represents the portion of microorganisms
discharged from the process.
In: Civil Engineering
Please write concrete specification in Performance approach
To make sure you understand what I mean, this is the 'Performance' approach for writing the specifications.
Performance (results) specifications Characteristics•
- Describe in detail the required performance or service characteristics of the finished product or system•
- Methods used to achieve desired results is left to the discretion of the contractor, but must be guaranteed
-Methods of testing and measurement, to evaluate the results, should be spelled out in the specifications.
In: Civil Engineering
In: Civil Engineering
1.What is a pre-bid subtrade proposal, and of what benefit is it to the contractor’s estimator?
a.To a general contractor?
b.To a subcontractor?
2.What is a pre-bid subtrade proposal, and of what benefit is it to the contractor’s estimator?
3.What are the benefits and disadvantages to a general contractor of having subtrades provide surety bonds?
In: Civil Engineering