the ultimate - amazon s3...find the ultimate bearing capacity for the square footing given the...
TRANSCRIPT
CIVIL PE BREADTH EXAM
Isaac Oakeson, P.E.Volume 1
THE ULTIMATE
HELPING YOU ON YOUR JOURNEY TO BECOMING A PROFESSIONAL ENGINEER.
Isaac Oakeson, P.E. is a professional engineer working in the great state of Utah. Having passed the PE Exam in the fall of 2012, he is driven to help others
do the same.
His passion has led him to create CivilEngineeringAcademy.com, CivilPEReviewCourse.com and CivilFEReviewCourse.com.
Each website provides the tools necessary to ace the FE and PE exams. Many have used the resources he has created and now he wants to help you too!
www.civilengineeringacademy.com | [email protected] |
TABLE OF CONTENTS
WELCOME…………………………………………….
EXAM SPECIFICATION……………………
START TEST ………………………………...
SOLUTIONS………………………………………
LAST SECOND TIPS AND ADVICE…..
Page 3
Page 6
Page 9
Page 43
Page 82
Page 3
www.civilengineeringacademy.com | [email protected] |
WELCOME!!
Welcome to The Ultimate Civil PE Breadth Practice Exam Volume 1!
Thank you so much for purchasing this book!
This book includes a full 40-question/solution breadth exam. This
exam makes the effort to be updated to the latest NCEES
specifications (2015 as of this writing). Each problem is designed to
have a similar look and feel to the real exam.
The key to passing the PE exam is to absolutely crush the breadth
portion of it. If you can get 90 percent or more in the morning
section, then the afternoon section will be that much easier on you.
All in all, this is to help you gain more practice, more experience, and
ultimately more confidence in passing.
This test is not endorsed by the NCEES organization. These are
problems that my team and I have written to help you succeed in
passing the PE exam. I would encourage you to take this timed to see
how long it takes you. Afterwards, you can take note of the areas that
you might need to work on. I have spent some time getting all of the
information here for you so that it is easy to use. Each problem is
labeled and sub-labeled so you know what problem and area you are
dealing with.
There are multiple ways of taking practice exams – you can work
problems like homework, you can take it like the real exam - it’s really
up to you! I would make sure to do at least one practice exam as if it
were the real deal though so you gain that experience.
Page 4
www.civilengineeringacademy.com | [email protected] |
As always, I value your feedback and any constructive criticism you
might have on this exam or anything else we produce to help others
pass. You can also get many more resources on the sites we run at
www.civilengineeringacademy and www.civilpereviewcourse.com,
including step by step video practice problems.
I know that with a lot of practice you will become much more
proficient at working problems and doing them with less and less
assistance. Keep at it and you will be prepared to pass the PE.
I don’t need to tell you about the benefits of obtaining your PE license,
because I’m sure you already know them. You must get it to have a
great career in civil engineering (and a lot of other fields!).
I wish you the best of luck!
Sincerely,
Isaac Oakeson, P.E.
(You’re going to have that by your name too!)
P.S. Errata for this, and any other Civil Engineering Academy exam,
can be found at www.civilengineeringacademy.com/errata.
Page 5
www.civilengineeringacademy.com | [email protected] |
LEGAL INFORMATION
Civil Engineering Academy’s
The Ultimate Civil PE Breadth Exam Vol. 1
Isaac Oakeson, P.E.
Rights and Liability:
All rights reserved. No part of this book may be reproduced or
transmitted by photocopy, electronic, recording, or any other method
without first obtaining permission from the author. The information in
this book is in no way endorsed by the NCEES organization and the
author shall not have any liability to any person with respect to any
loss or damage caused by the problems in this book.
In other words, please don’t go copying this thing willy-nilly without
giving credit where it should be given by actually purchasing a copy.
Also, don’t go designing real things based on these problems.
If you find errors in this book (I am human of course), or just want to
comment on things, then please let me know! I can be reached
through the website at www.civilengineeringacademy.com or by email
ABOUT THE AUTHOR
Isaac Oakeson, P.E. is a registered professional civil engineer in the
great state of Utah. Shortly after passing the PE exam in the fall of
2012 he started www.civilengineeringacademy.com and
www.civilpereviewcourse.com to help future students pass. He has
authored and helped author various exams with his entire goal of
providing the best resources for engineers to study and pass the PE.
Page 6
|www.civilengineeringacademy.com | [email protected] |
CIVIL – BREADTH EXAM SPECIFICATION
I. Project Planning (4)
A. Quantity take-off methods
B. Cost estimating
C. Project schedules
D. Activity identification and sequencing
II. Means and Methods (3)
A. Construction loads
B. Construction methods
C. Temporary structures and facilities
III. Soil Mechanics (6)
A. Lateral earth pressure
B. Soil consolidation
C. Effective and total stresses
D. Bearing capacity
E. Foundation settlement
F. Slope stability
IV. Structural Mechanics (6)
A. Dead and live loads
B. Trusses
C. Bending (e.g., moments and stresses)
D. Shear (e.g., forces and stresses)
Page 7
|www.civilengineeringacademy.com | [email protected] |
E. Axial (e.g., forces and stresses)
F. Combined stresses
G. Deflection
H. Beams
I. Columns
J. Slabs
K. Footings
L. Retaining walls
V. Hydraulics and Hydrology (7)
A. Open-channel flow
B. Stormwater collection and drainage (e.g., culvert, stormwater
inlets, gutter flow, street flow, storm sewer pipes)
C. Storm characteristics (e.g., storm frequency, rainfall measurement
and distribution)
D. Runoff analysis (e.g., Rational and SCS/NRCS methods,
hydrographic application, runoff time of concentration)
E. Detention/retention ponds
F. Pressure conduit (e.g., single pipe, force mains, Hazen-Williams,
Darcy-Weisbach, major and minor losses)
G. Energy and/or continuity equation (e.g., Bernoulli)
VI. Geometrics (3)
A. Basic circular curve elements (e.g., middle ordinate, length, chord,
radius)
B. Basic vertical curve elements
C. Traffic volume (e.g., vehicle mix, flow, and speed)
Page 8
|www.civilengineeringacademy.com | [email protected] |
VII. Materials (6)
A. Soil classification and boring log interpretation
B. Soil properties (e.g., strength, permeability, compressibility, phase
relationships)
C. Concrete (e.g., nonreinforced, reinforced)
D. Structural steel
E. Material test methods and specification conformance
F. Compaction
VIII. Site Development (5)
A. Excavation and embankment (e.g., cut and fill)
B. Construction site layout and control
C. Temporary and permanent soil erosion and sediment control (e.g.,
construction erosion control and permits, sediment transport,
channel/outlet protection)
D. Impact of construction on adjacent facilities
E. Safety (e.g., construction, roadside, work zone)
Page 10
|www.civilengineeringacademy.com | [email protected] |
1. Choose the correct activity-on-arrow diagram for the following
activities:
Activity Predecessor
A -
B -
C A, B
D B
2. The method of overlapping the design and construction phases of
a project is called:
a) Crashing
b) PERT
c) Fast Tracking
d) Precedence mapping
Page 11
|www.civilengineeringacademy.com | [email protected] |
3. Details of a beam are given below:
If steel reinforcement has a unit weight of 0.283 lbf/in3, how much
does the steel cost for a 3-ft length of beam given that the steel
has a price of $0.75 per lbf?
a) $13.20
b) $18.00
c) $17.45
d) $34.70
Page 12
|www.civilengineeringacademy.com | [email protected] |
4. A 400 ft long fill section is planned for a future embankment on a
construction site. The areas of fill sections are 75 feet apart. The
total volume of earthwork between stations 13+00 to 16+00 is
most nearly:
STATION AREA (ft2)
13+00 347.33
13+75 647.24
14+50 974.50
15+25 702.14
16+00 358.67
a) 7436 yd3
b) 8956 yd3
c) 9041 yd3
d) 3647 yd3
Page 13
|www.civilengineeringacademy.com | [email protected] |
5. A 15 ft wide x 18 ft deep trench in a clay soil is temporarily braced
as shown in the figure below. The longitudinal spacing of the
struts is 6 ft. Calculate the axial load in strut 1. 700 psfucS and
120 pcf .
a) 5.5 kips
b) 18 kips
c) 24.5 kips
d) 33.5 kips
Page 14
|www.civilengineeringacademy.com | [email protected] |
6. A 40-ton crane has four extendable outriggers that weigh 85,000
lbs. The pad of each outrigger has a diameter of 24 in. The soil
has an allowable soil contact pressure of 2500 psf. What area of
cribbing is needed under each outrigger if each outrigger sees the
total load?
a) 60 ft2
b) 65 ft2
c) 70 ft2
d) 75 ft2
Page 15
|www.civilengineeringacademy.com | [email protected] |
7. Which of the two mechanisms listed below are found to be the
major cause of crane failure?
a) Proper use of outriggers and ground conditions
b) Proper ground conditions and leveling
c) Stability and structural capacity
d) All of the above
8. Find the effective overburden pressure at a point 10 ft below the
water level.
a) 2313 psf
b) 2451 psf
c) 2461 psf
d) 3076 psf
Page 16
|www.civilengineeringacademy.com | [email protected] |
9. A 3 ft x 3 ft square footing carries a load of 3000 lbs including its
weight. The base of the footing is at 2 ft below the ground. The
sandy soil has a unit weight of 145 lb/ft3. Find the ultimate
bearing capacity for the square footing given the following bearing
capacity factors:
23 37 20q cN N N
a) 10368 lb/ft2
b) 9351 lb/ft2
c) 12470 lb/ft2
d) 8786 lb/ft2
Page 17
|www.civilengineeringacademy.com | [email protected] |
10. A retaining wall is shown in the figure below. The wall supports a
mass of cohesionless soil with a normal density of 85 lb/ft3, a
saturated density of 100 lb/ft³, a void ratio of 0.65, and an angle
of shearing resistance of 30°. The top of the wall is level with the
horizontal surface of the soil. By ignoring the wall friction,
determine the total earth thrust on the wall.
a) 8800 lbs
b) 5957 lbs
c) 6347 lbs
d) 12720 lbs
Page 18
|www.civilengineeringacademy.com | [email protected] |
11. A set of group piles has been determined to be placed for a
foundation. Which of the following is not true?
a) Piles bearing on rock virtually do not settle.
b) Piles in granular soils experience minimal settlement after
placement.
c) Piles in cohesive soils may experience very little settlement.
d) For piles in clay, the capacity is taken as the sum of the individual
capacities.
12. Slope stability in saturated clay is found using the Taylor Slope
Stability chart. Which of the following statements are not true
when using it to solve for slope stability?
a) There are no surcharges or tension cracks assumed.
b) For slopes less than 53°, toe circle failures occur.
c) For slopes less than 53°, slope circle failures occur.
d) Shear strength is derived from cohesion only and is constant with
depth.
Page 19
|www.civilengineeringacademy.com | [email protected] |
13. An 18 ft layer of clay is found between a sand layer of 3 ft and a
gravel layer of 5 ft. How long will it take to achieve a degree of
consolidation of 80%? Use vC = 4 ft2/year.
a) 3650 days
b) 16,790 days
c) 14,235 days
d) 4198 days
Page 20
|www.civilengineeringacademy.com | [email protected] |
14. A truss system is shown below. Compute the force on member BC.
a) 0 kips
b) 75 kips
c) 70 kips
d) 460 kips
Page 21
|www.civilengineeringacademy.com | [email protected] |
15. A cantilever solid steel shaft 6 inches in diameter and 7 ft long is
subject to torque as shown. The modulus of rigidity is 50109
lb/ft2. What is the maximum shearing stress in the shaft?
a) 2852 kips/ft2
b) 1623 kips/ft2
c) 2037 kips/ft2
d) 3213 kips/ft2
Page 22
|www.civilengineeringacademy.com | [email protected] |
16. The loads on a structure (dead and live) are shown below. Solve
for the closest approximate vertical reaction at B.
a) 138 lbs
b) 107 lbs
c) 55 lbs
d) 90 lbs
Page 23
|www.civilengineeringacademy.com | [email protected] |
17. What is the moment diagram most nearly for the load shown
below?
Page 24
|www.civilengineeringacademy.com | [email protected] |
18. Solve for the maximum bending stress on a beam which has 1 ft
width, 3 ft depth and 20 ft length. Assume the beam is simply
supported and loaded with a 200 kips/ft uniform load.
a) 151 kips/ft2
b) 9995 kips/ft2
c) 5667 kips/ft2
d) 6667 kips/ft2
Page 25
|www.civilengineeringacademy.com | [email protected] |
19. A newly installed building has a fixed span on the second floor that
is subject to a 2 kips/ft load. A W24x84 beam has been sized for
the span (I=2370 in4, E=29,000 ksi). What is the maximum
deflection on the beam if we neglect the self-weight of the beam?
a) 1 in
b) 0.002 in
c) 0.34 in
d) 1.68 in
Page 26
|www.civilengineeringacademy.com | [email protected] |
20. A trapezoidal canal with sides sloping 45° has a base width of 5 ft.
If the flow is has a 7 ft width, what is the hydraulic radius?
a) 0.77 ft
b) 0.81 ft
c) 0.74 ft
d) 0.69 ft
Page 27
|www.civilengineeringacademy.com | [email protected] |
21. What is the theoretical velocity of flow through a sharp edged
orifice located 10 ft below the water surface?
a) 25.38 ft/s
b) 24.87 ft/s
c) 25.72 ft/s
d) 26.74 ft/s
22. Which of the following statement is NOT TRUE about a detention
basin?
a) It is designed to store water temporarily as part of a flood control
management system.
b) If the flow exceeds the storage capacity an uncontrolled structure
provides an outlet for the excess water.
c) They are designed with no conservation pool.
d) It is used to hold water for an extended period of time and have a
conservation pool.
Page 28
|www.civilengineeringacademy.com | [email protected] |
23. Two pipes, 1 and 2, having the following properties are connected
in series:
Pipe 1: length = 4500 ft; diameter = 1 ft; f = 0.025
Pipe 2: length = 6000 ft; diameter = 0.75 ft; f = 0.020
If these two pipes are to be replaced by a single pipe with length
of 7000 ft, what will be the diameter? Use f = 0.018.
a) 4.70 ft
b) 0.73 ft
c) 1.20 ft
d) 0.91 ft
Page 29
|www.civilengineeringacademy.com | [email protected] |
24. Water is pumped through a 1.6 ft diameter circular pipe which is
2500 ft long at a velocity of 7.0 ft/s. Which of the following most
nearly gives the head loss using Manning’s formula if n = 0.013?
a) 52.8 ft
b) 17.4 ft
c) 29.5 ft
d) 31.6 ft
Page 30
|www.civilengineeringacademy.com | [email protected] |
25. A detention basin has been in service for 50 years. What is the
probability that a 2% flood occurred within the 50 year service?
a) 66%
b) 64%
c) 74%
d) 57%
26. The total net precipitation of a watershed was found to be 2.75 in.
The most downstream culvert of the area saw 45,000 ft3 of water
pass through it during the storm event. What is the total acreage
of the watershed area?
a) 3.9 acres
b) 4.1 acres
c) 4.5 acres
d) 0.38 acres
Page 31
|www.civilengineeringacademy.com | [email protected] |
27. A reversed curve of equal radii connects two parallel tangents 30
ft apart. The length of chord from P.C. to P.T. is 420 ft. Determine
the total length of the reversed curve.
a) 419.57 ft
b) 420.35 ft
c) 421.45 ft
d) 426.75 ft
Page 32
|www.civilengineeringacademy.com | [email protected] |
28. A car traveling at a constant speed approached a hazard on the
road and stepped on the brake. If the car travelled 80 ft from
perception of the hazard to the time the driver steps on the brake,
what is the perception-reaction time of the driver given that the
car has a constant speed of 30 mph.
a) 1.8 sec
b) 2.1 sec
c) 3.4 sec
d) 4.5 sec
Page 33
|www.civilengineeringacademy.com | [email protected] |
29. Given the following information, find the stationing at the low
point of the curve.
a) 21+47
b) 22+42
c) 23+67
d) 24+77
Page 34
|www.civilengineeringacademy.com | [email protected] |
30. A field density test on a compacted fill of sandy clay has the
following results:
Volume of test hole = 0.015 ft3
Weight of moist soil from the hole = 2 lbs
Oven-dried weight of the soil = 1.75 lbs
Maximum Dry Density = 118 lb/ft3
Optimum Moisture Content = 10%
Solve for the percent compaction of the soil.
a) 99%
b) 100%
c) 89%
d) 72%
Page 35
|www.civilengineeringacademy.com | [email protected] |
31. Refer to the following test data to solve this problem:
% passing #200 sieve 47
Liquid Limit 57
Plastic Limit 15
The AASHTO classification of this soil is:
a) A-7-5
b) A-7-6
c) A-5
d) A-6
Page 36
|www.civilengineeringacademy.com | [email protected] |
32. Cohesive borrow material has just been transported and spread to
the desired lift thickness at a fill site. What type of compaction
equipment is best suited for this job?
a) Smooth shell roller
b) Mesh roller
c) Sheepsfoot roller
d) Tamping foot roller
33. Stress versus strain curves are shown for various materials. Which
corresponds to a hard and strong material?
Page 37
|www.civilengineeringacademy.com | [email protected] |
34. An engineer is using the following boring log to design a caisson
foundation. What is the standard penetration resistance for the
soil at a depth of 23 ft?
a) 4
b) 8
c) 3.7
d) 44
Page 38
|www.civilengineeringacademy.com | [email protected] |
35. Given the figure below, determine the discharge. Water is flowing
perpendicular to the soil layers.
Soil 1: 0.00065 ft/sKx
Soil 2: 0.0006 ft/sKx
Soil 3: 0.001 ft/sKx
Cross sectional area = 2.5 ft2
a) 0.00089 ft3/s
b) 0.00075 ft3/s
c) 0.00066 ft3/s
d) 0.00022 ft3/s
Page 39
|www.civilengineeringacademy.com | [email protected] |
36. The ground makes a uniform slope of 3.2% from Station 1+980 to
Station 2+120. At Station 1+980, the center height of the road is
1 m fill. At Station 2+120, the center height of the road is 3.2 m
cut. Find the grade of the finished road.
a) 0.2%
b) 0.5%
c) 0.01%
d) 0.02%
Page 40
|www.civilengineeringacademy.com | [email protected] |
37. A road with dimensions of 100 ft length, 16 ft width, and 2 ft thick
needs to be constructed. The moisture content of the compacted
road needs to be 15% with a wet density of 110 lb/ft3. If the
borrow pit has a soil with a wet density of 100 lb/ft3 and a
moisture content of 10%, what is the required volume of soil from
the borrow pit that needs to be hauled?
a) 3270 ft3
b) 3520 ft3
c) 3370 ft3
d) 3450 ft3
Page 41
|www.civilengineeringacademy.com | [email protected] |
38. Choose the correct construction sequence:
a) Pre-mobilization, Layout, Excavation, Footing Concreting
b) Layout, Footing Concrete, Excavation, Pre-mobilization
c) Layout, Pre-mobilization, Excavation, Footing Concrete
d) Pre-mobilization, Excavation, Layout, Footing Concrete
39. 200 ft3 of soil from a borrow pit was excavated, transported by
truck to the construction site, and finally compacted. The soil has
a swelling factor of 0.2 and shrinkage factor of 0.15. What was the
volume of the soil while being transported by the truck?
a) 170 yd3
b) 7.6 yd3
c) 8.9 yd3
d) 6.3 yd3
Page 42
|www.civilengineeringacademy.com | [email protected] |
40. If a construction worker is entering a confined space, what is the
amount of oxygen content that must be maintained?
a) 10.5%
b) 15.5%
c) 20%
d) 5.0%
Page 44
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 1 SOLUTION:
PROJECT PLANNING
ACTIVITY IDENTIFICATION AND SEQUENCING
This is a complicated problem because of the “dummy activity” that
must be included in order to maintain the correct order and
precedence. Activity D depends on B only (drawn as answer A), but C
depends on A and B, which answer C might confuse you with, but it is
wrong because that means activity C happens twice and it doesn’t. In
order to draw this correctly you have to have a “dummy activity” to
show the activities in order of precedence. Answer D is just wrong.
(Answer B)
PROBLEM 2 SOLUTION:
PROJECT PLANNING
PROJECT SCHEDULES
Besides efficient scheduling, construction time can be compressed with
fast-track scheduling. This particular method overlaps the design and
construction phases of a project.
(Answer C)
Page 45
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 3 SOLUTION:
PROJECT PLANNING
COST ESTIMATING
Obtain the total mass of steel:
For the links:
For every 3-ft, there will be:
Number of links = 3’ length / 8” spacing or (36”/8”)
= 4.5 ≈ 5 links
Total length per link = 8" 2 16" 2 20" 2 4" 2 96"/link
Since there are 5 links on a 3-ft length of beam:
Total length = 96"/link 5 links 480"
To obtain the volume, multiply the total length by the area:
Volume =
2
33480 in in 53.0144 in
4 8
For the main bars:
Since there are 10 bars on a cross section:
Total volume for 3-ft length of steel,
Volume =
2
3510 bars 36 in in 110.4466 in
4 8
Total Volume of steel considering links and main bars:
Page 46
|www.civilengineeringacademy.com | [email protected] |
Total Volume = 3 3 353.0144 in 110.4466 in 163.461 in
Total Mass = Total Volume density
= 3 3163.461 in 0.283 lbf/in 46.2595 lbf
Calculate the price:
Total Price = $0.75/lbf 46.2595 lbf $34.69
(Answer D)
Page 47
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 4 SOLUTION:
PROJECT PLANNING
QUANTITY TAKE-OFF METHODS
You can solve this by using the trapezoidal method or you can solve
this by intuitively thinking about it. I’m using the later here.
First, let’s draw it out in plan view and look at the tributary areas of
each fill zone:
Now just multiply everything out and convert the volume to yd3:
3 3
347.33 37.5 647.24 75 974.50 75 702.14 75 358.67 37.5
200766 ft 7435.8 yd
(Answer A)
Page 48
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 5 SOLUTION:
MEANS AND METHODS
TEMPORARY STRUCTURES AND FACILITIES
For this temporary structure we must first test what type of soil we are
in. If H
c
is greater or equal to 6 then we are dealing with soft clay.
c (cohesion) = 1 1
700 350 psf2 2
ucS
H is total depth of the trench.
120 186.17 6 it is a soft clay
350
H
c
The lateral pressure is linear for the top 4.5 ft4
H of the depth and
then stays at a constant ( maxP ) after that.
max4 120 18 4 350 760 psfP H c
10.5 760 psf 4.5 ft 1710 lb/ftR
2760 psf 4.5 ft 3420 lb/ftR
Page 49
|www.civilengineeringacademy.com | [email protected] |
Make a hinge at strut 2 and take the moment about strut 2. We will
include the 6 ft longitudinal spacing here too:
2
1 2 1
1
1
0
6 2.25 6 0
1710 6 3420 2.25 6 0
2992.5 lb/ft
sM
R R S
S
S
Because the longitudinal spacing is 6 ft, then:
12992.5 lb/ft 6 ft 17955 lb 18 kipsS
(Answer B)
Page 50
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 6 SOLUTION:
MEANS AND METHODS
CONSTRUCTION LOADS
First, find the total load:
Crane = 40 tons x 2000 lbs = 80,000 lbs
Outriggers = 85,000 lbs
Total = 165,000 lbs
We were given a soil pressure of 2500 psf. Therefore, the area of the
cribbing needed is:
2 2165000 lbsArea 66 ft 70 ft
2500 psf
(Answer C)
It should be noted that each outrigger sees the total load. If this
wasn’t the case we would have divided the load by 4 outriggers.
Page 51
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 7 SOLUTION:
MEANS AND METHODS
CONSTRUCTION METHODS
Cranes can fail two different ways which are by stability and structural
capacity; and within those 2 categories you will find every option listed
in the answers.
(Answer D)
PROBLEM 8 SOLUTION:
SOIL MECHANICS
EFFECTIVE AND TOTAL STRESS
At point 10 ft below the water level you are placed 5 ft into the clay
layer. That means you need to calculate the stress in 3 different layers
with 2 of those being in water. The dry layer is total stress and the
saturated layers will be the effective stress.
Total stress = H
Effective stress = 'H where 'w
Most sand layer 3 2130 lb/ft 15 ft 1950 lb/ft
Saturated Sand Layer 3 3 2135 lb/ft 62.4 lb/ft 5 ft 363 lb/ft
5’ into clay layer 3 3 290 lb/ft 62.4 lb/ft 5 ft 138 lb/ft
Total effective overburden pressure 21950 363 138 2451 lb/ft
(Answer B)
Page 52
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 9 SOLUTION:
SOIL MECHANICS
BEARING CAPACITY
Using Terzaghi’s ultimate bearing capacity equation for a square
footing:
1.3 0.425u c f qq cN D N BN
Where:
c = cohesion
fD = depth to base of footing
B = width of footing
1.3 = cN multiplier value for a square footing
0.425 = N multiplier value for a square footing ( 0.85 0.5 )
Remember that sandy soil has no cohesion. Therefore, the first
component of the equation will be zero.
3 3
2
0 145 lb/ft 2 ft 23 0.425 145 lb/ft 3 ft 20
10368 lb/ft
u
u
q
q
(Answer A)
Note:
The value of 3000 lbs mentioned in the problem is meant to confuse
you. You are solving for what loads the soil can take. Because the load
is 23000 lbs
333 lb/ft3 ft 3 ft
, this soil will be fine.
Page 53
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 10 SOLUTION:
GEOTECHNICAL
LATERAL EARTH PRESSURE
1 sin 1 sin30 1
1 sin 1 sin30 3aK
(Don’t forget the active earth pressure!)
aK is the active earth pressure coefficient and is only applied to the
soil, not to the water.
3 3 2
2
1100 lb/ft 62.4 lb/ft 10 ft 125.3 lb/ft
3a
P K H
3 2
362.4 lb/ft 10 ft 624 lb/ft
wP H
Solving for the forces (areas of each):
2
3
1125.3 lb/ft 10 ft 1 ft 626.5 lbs
2F
2
4
1624 lb/ft 10 ft 1 ft 3120 lbs
2F
(Answer B)
Page 54
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 11 SOLUTION:
SOIL MECHANICS
FOUNDATION SETTLEMENT
Piles in cohesive soils my, in fact, experience significant settling. The
rest of the answers are true.
(Answer C)
PROBLEM 12 SOLUTION:
SOIL MECHANICS
SLOPE STABILITY
The only statement that is not true (false) in the answer selection is B.
The Taylor chart shows that toe circle failures occur in slopes steeper
than 53°.
(Answer B)
Page 55
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 13 SOLUTION:
SOIL MECHANICS
SOIL CONSOLIDATION
If a clay layer is between a sand and gravel layer this means that the
soil is double draining. This makes H in the following equation halved.
Using the table for time factors (table 40.1 in CERM) for 80%
compaction you get 0.567vT . Plug everything into the following
equation and solve:
2 20.567 911.5 years or 4198 days
4v
v
T Ht
C
Note:
t = time to consolidate
vT = time factor
H = height of clay layer
vC = coefficient of consolidation
(Answer D)
Page 56
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 14 SOLUTION:
STRUCTURAL MECHANICS
TRUSSES
Solve for the reactions first and then make a cut at section Z-Z:
0
21 100 14 200 10.5 100 7 420 5 0
100 kips
A
v
v
M
G
G
0
21 100 14 200 10.5 100 7 420 5 0
300 kips
G
v
v
M
A
A
0
420 0
420 kips
H
H
H
F
A
A
Page 57
|www.civilengineeringacademy.com | [email protected] |
0
3 3.5 3 0
420 3 300 3.5 3 0
70 kips
H
H v
M
A A BC
BC
BC
(Answer C)
The sign convention doesn’t matter in this question because we are
just looking for the magnitude of the reaction not whether it is in compression or tension.
Page 58
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 15 SOLUTION:
STRUCTURAL MECHANICS
SHEAR STRESS
Solve for the torque between each section (start from point D to A):
Torque at point D = -50 kip-ft
Torque at point C = -50 + 40 = -10 kip-ft
Torque at point B = -10 - 60 = -70 kip-ft
Torque at point A = -70 kip-ft
From the torque diagram, the maximum torque = 70 kip-ftABT .
Calculate the maximum shear stress:
First, derive equation for circular shaft design from CERM Eq. 45.50.
maxmax max
4 3
0.5 16
32
D TrT TS
J D D
Therefore, the maximum shear stress is:
2max
3 3
16 16 702852 kips/ft
0.5
TS
D
(Answer A)
Page 59
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 16 SOLUTION:
STRUCTURAL MECHANICS
LOADS
Solve for the angle and length of EB using Pythagorean Theorem:
2 2 25 10.6
11.72 ft
EB
EB
5
tan 25.2510.6
Solve for the force F:
length of 20 11.72 234.4 lbsF w EB
Now take the moment about point A (CCW as positive):
0
21.2 120 10 sin 7.5 cos 15.9 0
21.2 120 10 234.4sin25.25 7.5 234.4cos25.25 15.9 0
137.8 lbs
A
y
y
y
M
B F F
B
B
(Answer A)
Note: The force F is broken into its X and Y components
for ease of solving for its moment arm about point A.
Page 60
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 17 SOLUTION:
STRUCTURAL MECHANICS
MOMENT DIAGRAM
Let’s first solve for the reactions (this is the long way so solve this
thing). Take + as counter clockwise:
0
22.5 kips 6 ft 9 ft 0
15 kips
A
B
B
M
F
F
0
15 kips 22.5 kips 0
7.5 kips
Y
A
A
F
F
F
From the shear diagram 0 to 5.2 ft, the
value of shear is decreasingly positive,
so the slope of the moment diagram is
also decreasingly positive (dm/dx=V).
Everything past 5.2 ft on the shear
value is increasingly negative so the
slope of the moment is increasingly
negative. The short way is to look at
the Appendix 44A of the CERM for a
triangular load case It should help with
other scenarios too.
(Answer C)
Note: -22.5 kips is found by taking
the area of a triangle (0.5BH) for the
distributed area and applying it at a
distance 1/3 from the base.
Where the shear is 0, the moment has a
maximum. The area under the curve
leading up to 0 is the maximum value for
the moment. Because the load is linear, the
shear diagram is of the second degree (X2)
and the moment diagram would be the
n+1 degree of the shear (X3).
The distance of 3.46 ft was
found by using the method of
sections and getting the
equation of a line.
Solve for when V=0 by FY
and solve for x:
7.5 – 0.5(5(x/9))x = 0
x = 5.2 ft
Page 61
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 18 SOLUTION:
STRUCTURAL MECHANICS
BENDING
To solve for the maximum bending stress, first find the max moment,
which is at the mid-span of a simply supported beam loaded uniformly
throughout its length.
2
2
max
200 kips/ft 20 ft10000 kips-ft
8 8
wLM
Then solve for the maximum bending stress using the formula for max
bending stress on a rectangular cross-section:
2max
2 2
6 6 10000 kips-ft6666.67 kips/ft
1 ft 3 ftb
Mf
bd
(Answer D)
Page 62
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 19 SOLUTION:
STRUCTURAL MECHANICS
DEFLECTION
We are given from the problem statement the following:
w = 2 kips/ft
E = 29,000 ksi
I = 2370 in4
Solve for deflection with this size of beam and a fixed-fixed end
connection:
4
4
max 4
2 kips/ft5 40 ft 12 in/ft
5 12 in/ft1.676 in
384 384 29000 ksi 2370 in
wL
EI
(Answer D)
Page 63
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 20 SOLUTION:
HYDRAULICS AND HYDROLOGY
OPEN CHANNEL FLOW
Solve for the depth d and y:
7 ft 5 ft1 ft
2x
sin45
1 1 ft
2
1.4142 ft
d
y
y
y
tan45
11 ft
1 ft
d
x
d
d
Solve for Hydraulic Radius (R):
21Area 5 ft 1 ft 1 ft 1 ft 2 6 ft
2
Perimeter 5 ft 2 5 ft 2 1.4142 ft 7.8284 fty
26 ft
0.766 ft7.8284 ft
AR
P
(Answer A)
Page 64
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 21 SOLUTION:
HYDRAULICS AND HYDROLOGY
ENERGY EQUATION
Derived from the Bernoulli’s Equation:
2 (Eq 17.66)tv gH
Sharp edged orifice 0.98vC
→ (Note that Cv only used for actual velocity)
2 2 32.2 10 25.38 ft/stv gH
(Answer A)
PROBLEM 22 SOLUTION:
HYDRAULICS AND HYDROLOGY
DETENTION/RETENTION PONDS
Detention basins are used to store water temporarily as part of a flood
control system. They have no conservation pool. The only false answer
is D. A retention basin is used to hold water for an extended period of
time.
(Answer D)
Page 65
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 23 SOLUTION:
HYDRAULICS AND HYDROLOGY
PRESSURE CONDUIT
For pipes in series:
1 2
1 2
eq
eq
HL HL HL
Q Q Q
Using Darcy’s equation:
2
2
5
2 2
5 5
2
(1)
2
0.025
(2)
0.025 0.025 4500 0.025 0.020 6000
1 0.75
15.45
eq
L VHL f
D g
f L QHL
D
Q QHL
Q
For the equivalent pipe:
2
2
5
0.025 0.018 700015.45
0.73 ft
eqHL HL
D
D
(Answer B)
(CERM Eq. 17.28)
Page 66
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 24 SOLUTION:
HYDRAULICS AND HYDROLOGY
LOSSES
Using the Manning’s Equation, the slope can be found:
21.64 0.4 ft
1.6
AR
P
2 13 2
2 13 2
1.49
1.497 0.4
0.013
0.01266
V R Sn
S
S
To get the head loss, use the slope and length of the pipe:
head loss
length of pipe
head loss0.01266
2500
head loss 31.64 ft
S
(Answer D)
Page 67
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 25 SOLUTION:
HYDRAULICS AND HYDROLOGY
STORM CHARACTERISTICS
Note (see Eq. 20.20):
1% = 100 year frequency
2% = 50 year frequency
5% = 20 year frequency
Probability (50 year flood in 50 years) = 50
1 1 0.02 0.64 64%
(Answer B)
PROBLEM 26 SOLUTION:
HYDRAULICS AND HYDROLOGY
RUNOFF ANALYSIS
Solve by using rational method (Eq. 20.36):
Q CiA
C isn’t given in the problem, so it is assumed to be 1.
I = 2.75 in/time
Q = 45,000 ft3/time
3
2
in 1 ft45,000 ft /time 1 2.75
time 12 in
196363.64 ft 4.5 acres
Q CiA
A
A
(Answer C)
Page 68
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 27 SOLUTION:
GEOMETRICS
BASIC CURVE ELEMENTS
In triangle (a):
30
sin 4.096420
2 8.192I
In triangle (b):
105sin
105sin4.096
1470 ft
R
R
R
Use the length of curve equation:
1470 ft 8.192
2 2 420.35 ft180 180
c
RIL
(Answer B)
Page 69
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 28 SOLUTION:
GEOMETRICS
TRAFFIC VOLUME
Even without the knowledge of transportation engineering, this
problem can be solved by equations of motion. Using the equation for
constant velocity (since the driver is yet to step on the brake):
ft 1 hr80 30 mph 5280
mile 3600 sec
1.82 1.8 sec
ox v t
t
t
(Answer A)
Page 70
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 29 SOLUTION:
GEOMETRICS
BASIC VERTICAL CURVE ELEMENTS
First, find the stationing at the low point of the curve and then solve
for the station at that location:
1 2 1
2 1
1
and
2450 1950 500 5 stations
2.5% 3.5%1.2% per station
5 stations
3.5%Sta 2.9166 291.67 ft
1.2% / station
turn
turn
G G GX R
R L
L
G GR
L
GX
R
Now add the station to BVC to get the location of the low point:
,1950 291.67 2241.67 ft Sta 22 42
turn sta turn staX BVC X
(Answer B)
Page 71
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 30 SOLUTION:
MATERIALS
COMPACTION
Solve for the dry density:
3
3
1.75 lb116.67 lb/ft
0.015 fts
dry
w
V
Dry Density 116.67Percent Compaction 98.87%
Maximum Dry Density 118
(Answer A)
Page 72
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 31 SOLUTION:
MATERIALS
SOIL CLASSIFICATION
Using the AASHTO classification system (CERM Table 35.4) you will
find the following:
47% passes the #200 sieve so that limits the choices to A-4, A-5, A-6,
A-7.
The LL is 57 and the PL is 15 so the PI (Plasticity Index) = LL-PL = 42.
That leaves you in the A-7 column.
Now you have to break it down to either A-7-5 or A-7-6.
If the PL is less than 30 it is an A-7-6, and for a PL that is 30 or
greater it would be A-7-5. Remember that the PL = LL-PL.
(Answer B)
Page 73
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 32 SOLUTION:
MATERIALS
COMPACTION
Sheepsfoot rollers are best suited for cohesive soils. Smooth wheel
rollers are good for all kinds of soils but are mostly used for
compacting asphalt pavements. Mesh rollers are used for rocky soils
and gravel. The tamping foot roller is best used for compacting fine-
grained soils.
(Answer C)
PROBLEM 33 SOLUTION:
MATERIALS
MATERIAL TESTING
“A” is for a soft and weak material, “B” is for a weak and brittle
material, “C” is for a strong and tough material.
(Answer D)
Page 74
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 34 SOLUTION:
MATERIALS
BORING LOG INTERPRETATION
Standard penetration resistance, or blow count, is the number of blows
required to drive a sampler (140 lb hammer) a distance of 12 in. On
boring logs, it is the last two values added up (last 12 in of 18 in
bored). Option A is the last number in the blows measured (3-4-4).
Option C is the average of all three measurements and option D is just
a random number.
The purpose of this test is to get the relative density of the soil.
(Answer B)
Page 75
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 35 SOLUTION:
MATERIALS
SOIL PROPERTIES
You must solve for an equivalent coefficient of permeability (not in the
CERM but see page 21-2).
1 2 3
31 2
1 2 3
equivalent
H H HKy
HH H
K K K
; 1 1 2 2 3 3
1equivalent
Kx H K H K H KH
Since flow is perpendicular to the soil layer us Ky:
4
4 4 4
2 2 27.13 10 fps
2 2 2
6.5 10 6 10 10 10
equivalentKy
30.5
6
HiL
(in this case, H is the difference in water levels)
2.5A (given)
4 37.13 10 0.5 2.5 0.00 ft /s089 Q KiA
(Answer A)
Page 76
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 36 SOLUTION:
SITE DEVELOPMENT
CUT AND FILL
Consider the slope of the ground = +3.2%
Since the run is 140 m:
rise = run x slope = 140 m x 0.032 = 4.48 m
Cut is 3.2 m in the end station.
Solve for x:
x = 4.48 m – 3.2 m = 1.28 m
Knowing that at the starting station, there is a fill of 1.0 m, and the
end station of the road is 1.28 m, the end station of the road is higher
0.28 m than the starting station.
Therefore, solving for the slope of the road:
Slope of the road rise 0.28 m
0.2%run 140 m
(Answer A)
Page 77
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 37 SOLUTION:
SITE DEVELOPMENT
EXCAVATION AND EMBANKMENT
Volume of the compacted soil length width height
3
100 16 2
3200 ft
The only constant between the two states of soil even after
compaction is the mass of solids (sM ).
Find the sM on the compacted state:
110 pcf95.65 pcf
1 1 0.15wet
dryw
395.65 pcf
3200 ft
306087 lbs
s sdry
s
M M
V
M
(also equal to the sM of the soil in the borrow pit)
Using the moisture content (w) of the soil in the borrow pit to find
mass of water (wM ):
0.1306087 lbs
30608.7 lbs
w
s
w
w
Mw
M
M
M
Therefore, the total mass of the soil in the borrow pit is s wM M :
306087 30608.7 336695.7 lbstotalM
Page 78
|www.civilengineeringacademy.com | [email protected] |
Note:
It can be noticed that the required volume of soil from the borrow pit
is greater. This is because after hauling, the soil will be compacted,
thus reducing its volume.
Utilizing the wet density of the soil in the borrow pit, the volume of the
soil needed to be hauled can be solved:
3
336695.7 lbs100 pcf
3367 3370 ft
totalwet
M
V
V
V
(Answer C)
Page 79
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 38 SOLUTION:
SITE DEVELOPMENT
CONSTRUCTION SITE LAYOUT AND CONTROL
The correct answer in this sequence is A. The others are out of order
for proper a proper construction sequence.
(Answer A)
PROBLEM 39 SOLUTION:
SITE DEVELOPMENT
SEDIMENT CONTROL
The volume of the soil while being transported is larger since it swells.
3
3 3 3 3
Volume in truck volume on the borrow pit 1 swell factor
200 ft 1 0.2
240 ft 8.9 yd (1 yd = 27 ft )
(Answer C)
FYI - The volume of the soil after compaction is smaller since it shrinks
after compaction.
3
3 3 3 3
Volume after compaction volume on the borrow pit 1 shrinkage factor
200 ft 1 0.15
170 ft 6.3 yd (1 yd = 27 ft )
Remember that the given factors are for the original volume and NOT
the factor for the intermediate volumes.
Page 80
|www.civilengineeringacademy.com | [email protected] |
PROBLEM 40 SOLUTION:
SITE DEVELOPMENT
SAFETY
Based on OSHA 1926.651, if an employee is entering a confined space
there must be 19.5% oxygen content or higher. The correct answer is
C, 20%. See CERM Construction and Job Site Safety as well.
(Answer C)
Page 81
|www.civilengineeringacademy.com | [email protected] |
SCORE SHEET
Correct Answers: ___________
Percentage: (correct answers)/40 = ____/40 = ______
Remember that you should shoot for above 90%. Don’t be
discouraged if you aren’t there yet. Just keep practicing and you’ll get
there. I promise. You need approximately 70% to pass the PE exam.
So if you can ace the morning you need only get half right in the
afternoon to get it. Say you got 35 right in the morning then you
would need to get 21 right in the afternoon to get 70% (56/80 =
70%).
Page 82
|www.civilengineeringacademy.com | [email protected] |
LAST SECOND ADVICE AND TIPS
I wanted to wrap up this exam with some tips that I found helpful
when I took the exam. Hopefully, they will help you:
1) Make sure you fully understand what your state board and the
NCEES requires of you to take the PE exam and to receive your
PE. Comply with all rules.
2) You typically need about 3-4 months to really study for the PE.
Map out a schedule and study your depth section first. This will
allow you to make any adjustments as you get closer to test
time. I personally broke down the specification into the 5 major
categories of: water resources, transportation, geotechnical,
structural, and construction, and spent a couple weeks on each
topic with more time devoted to my depth section.
3) Practice everything with the calculator you are going to use on
the real exam. You need to become intimately familiar with it.
4) Know where your exam is, where to park, and where you will get
food (if you don’t plan on bringing your own). Don’t be stuck
trying to figure this out on test day. You’ll regret it.
5) Review courses help. If you can’t get motivated, or need the
extra help and accountability they offer, then consider taking
one. It’s worth it to get your PE and get that boost to your
career. If you’re wondering which one, refer to our helpful tools
below.
Helpful Tools:
We have built www.civilengineeringacademy.com to help any civil
engineer become a PE. We have tons of free video practice problems
there to get you going. We also have plenty of tips, must have
resources, advice on courses, and more practice exams that cover
your depth section. In addition to this, we have created a civil PE
review course that can guide you step-by-step through the entire
exam. You can check that out at www.civilpereviewcourse.com.
Page 83
|www.civilengineeringacademy.com | [email protected] |