CE315-101 Final Report
Each of you will submit your own final report. Final report will be included in your final score for
CE315. Please read through the requirement of the final report. This is NOT like your memo, or
group report. The evaluation rubric is attached.
Technical Content
Your final report should include all the data you measured during the lab this semester:
(1) Aggregate: coarse aggregate unit weight, gradation; fine aggregate gradation
(2) Portland Cement Concrete: mix design, concrete fabrication, slump, unit weight, and
compressive strength
This report is designed to present a complete professional document explaining the procedure,
outcome, and recommendations of the test or series of tests. This document should be treated as a
formal report that will be submitted to a client for project recommendations. Reports must include
the following information and will be graded accordingly.
1. General information
a. The report should be neat in appearance with sufficient margins and have
“Justified” text.
b. Be written in third person and be brief but complete. Content is more important
than length.
c. A stranger unfamiliar with the particular experiment should find the answers to the
following questions in the report: Who?, When?, Where?, What or Why?, Theory
or Practice?, Using or Testing what?, How?, and Results?
d. Page numbers should be used at the bottom of the page and centered. Do not number
the Cover Sheet, but do count it in the number of pages.
2. Divisions of the Report:
To simplify the report writing, the report will be segregated into divisions. Each division
must be included in the report, unless otherwise specified, in the order given below. Allow
two to three spaces between the end of one major division and the heading of the next.
Only the Table of Contents, Letter of Transmittal, Abstract, first page of the report
beginning with Introduction, Appendix Flysheet, and the Appendices should begin on new
sheets.
The order of the divisions will be as follows:
a. Cover Sheet (Page No. i, do not put a page number on the cover sheet)
i. Follow the format of the Cover sheet of the attached page (Appendix C)
b. Table of Contents (Start a new page)
c.
d.
e.
f.
g.
h.
i. List all divisions and subdivisions of the report including the Letter of
Transmittal with the corresponding page numbers
ii. Word can create this for you (Google “Styles and Table of Contents”)
Letter of Transmittal (Start a new page)
i. This is a business letter written to the client written in first person
ii. Includes a brief summary of the objectives, results, conclusions, and
recommendations to properly introduce the report to the reader
Abstract (Start a new page)
i. The abstract applies to the report as opposed to the test or experiment and
should be 100 words or less and concisely state
1. What the problem is and what the author has done
2. How it was done (if that is important)
3. The principal results (numerically, when possible)
4. The significance of the results (important conclusions)
ii. The abstract should not include any references, figures, or tables.
Introduction (Page no. 1)
i. A clear, concise statement should be given of the purpose, significance, and
benefits to be derived from the experiment.
Literature Survey and Theory
i. The basic theory and the fundamental principles on which the investigation
rests should be stated precisely so as to prepare for the experimental work
which will follow in the rest of the report. All equations used in the report
must be either reported from the literature survey or derived in this division.
ii. Reference all materials according to the standards of ASCE.
Procedural Outline
i. Brief description of the procedure
ii. List any standard procedures followed and any deviations if applicable
iii. A notation of the accuracy of the results
iv. A schematic sketch or photo may be included of the equipment used. In
addition to images, sufficient explanatory information is necessary to
identify all equipment.
v. A list is helpful and information such as type, manufacturer, serial number,
range and readability (if applicable)
Results and Discussion
i. This division includes tables, graphs, comments, analysis and discussion of
the results obtained or of the operation of the test or experiment.
ii. Tables shall consist of only the information pertinent to the purpose of the
testing or research and is usually consistent of some or all of the calculated
and theoretical values. Each table is numbered consecutively with a title at
the top of the table.
iii. Graphs should be used to better organize or present data that is calculated
or obtained. The scales of the axes should be chosen carefully to present the
data in a reasonable fashion. Each axes requires a label and the appropriate
unit of scale. Each graph should be considered a figure and is numbered
consecutively with other figures (or images listed as figures) with a title at
the bottom of the figure.
iv. The analysis and discussion of the results are the most important aspects of
the report. Be brief but present a complete analysis of the results obtained.
Relate results already presented to some authority, if possible. If there are
any errors that effect the results or that were evident during the testing,
present possible sources and tell how these can be deleted in future testing.
Limitations of the apparatus and resulting experimental accuracy should be
discussed.
i. Conclusions
i. Summarize the entire report.
ii. Indicate how the results are related to the objectives of the test or
experiment.
iii. Note that the conclusions apply to the test or experiment, not the report.
j. References
i. The references used in the preparation of the report shall be listed and
formatted according to ASCE.
k. Appendix (Start a new page)
i. An Appendix Flysheet should start the division with the word Appendices
centered in the middle of the sheet.
ii. Start a new page for each appendix section (labeled A, B, etc)
iii. Appendix material should be any information that is pertinent to further
explain a topic discussed in the report, but was not necessary to fully present
an idea, theory, or calculation.
iv. Further calculations, derivations, images, or background data may be
presented in an appendix.
University of South Alabama
Department of Civil, Coastal, and Environmental Engineering
CONSOLIDATION OF DIRT
Dave Jones
CE315 Section 101
November 13, 2017
CE 315: Civil Engineering Materials Lab
Formal Report Evaluation
Name: ____________________________________
The report will be evaluated for technical correctness, clarity of explanation, grammar, and
spelling.
Maximum Points
Cover Sheet
2
Table of Contents
2
Letter of Transmittal
5
Abstract
8
Introduction
8
Literature Survey
8
Procedural Outline
7
Results and Discussion
15
Conclusions
10
Citations and References
5
Technical Writing (grammar, paragraph and
sentence structure, technical language, etc.)
25
Appendices
5
Subtotal (100 possible)
Grading rubric attached and filled out
-5
Submitted on USA Online and paper copy
-10
Evaluation date
Total
Score
UNIVERSITY OF SOUTH ALABAMA
Shenghua Wu, Ph.D., LEED AP
September 5, 2017
Department of Civil, Coastal, and Environmental Engineering
University of South Alabama
Subject: CE 315 Civil Engineering Materials-Lab #1: Specific Gravity, Absorption of Coarse
Aggregates, Bulk Unit Weight & Voids in Aggregates
Dr. Wu,
The report below includes the results of the experiment to determine the Specific Gravity,
Absorption, Bulk Unit Weight, and Voids in Coarse Aggregate. The experiment was conducted on
August 28, 2017, in the civil engineering lab following the procedures outlined in the book
“Materials for Civil and Construction Engineers” for ASTM C17 and ASTM C29. Two
experiments were carried out i.e. experiment No. 7 for determining Specific Gravity and
absorption of Coarse Aggregates and experiment No. 9 for determining Bulk Unit Weight and
Voids in Aggregates. The research team included Ali Alshehri, Shadi Alzahrani, and Cory Judkins.
The mass of the empty water tank was first determined which was 0.74 lb and then mixing
aggregate and sample which was 8.26 lb. The aggregate was in the water for 24 hours, so this step
was not needed in this lab. The specimen was then removed from water and rolled in a large
absorbent cloth to remove water. The sample was then weighed which was the SSD and equal 7.98
lb. The sample was placed in the wire basket to measure its weight after shaking the basket just a
little bit to ensure all entrapped air has been removed and we got the submerged weight of 4.17 lb.
Finally, we put the sample in the oven and its dry weight recorded as 7.12 lb the following day.
After finishing this experiment, we determined the bulk Unit Weight. The weight of the pan was
determined which was 7.76 lb. Then, the weight of the pan with the sample was 32.62.lb. Since
the volume of the sample was provided as 5.32 in3, the value for Unit Weight of Aggregate (M)
was then computed. Finally, the void content was determined.
The results of the experiment were computed as follows.
For Experiment No. 7:
Bulk Specific Gravity = A/ (B - C) = 7.12/ (7.98 – 4.18) = 1.87
Where;
A = mass of oven-dry sample in air, (g)
B = mass 0f saturated surface-dry sample in air, (g)
C = mass of saturated sample in water, (g)
Bulk Specific Gravity (SSD) = B/ (B – C) = 7.98/ (7.98 - 4.18) = 2.10
Apparent Specific Gravity = A/ (A - C) = 7.12/ (7.12 – 4.18) = 2.422
Absorption, % = [(B – A) / A] * 100 = [(7.98 – 7.12) / 7.12] * 100 = 12.08%
For Experiment No. 9:
Bulk Unit Weight, M = (G – T)/ V = (32.62 – 7.76)/ 532 = 0.05 lb/in3 or 86.38 lb/ft3
Void content,
% VS = [ᵞb/ (Gsb * ᵞb)] * 100 = [86.38/ (1.87 * 62.3)] * 100 = 74.15%
% Voids = 100 - % VS = 100 – 74.15 = 25.85%
The results designate that the course aggregates utilized had low void content. The
accuracy of the results might have been affected by some errors with occurred during
experiments. A balance accurate to 0.05% of the sample weight was utilized to ensure high
accuracy. It is recommended that several experiments should be carried on and the average
value obtained in order to improve the accuracy of the results (Mamlouk et al, 2011).
Thank You
Ali Alshehri
Attachments: Photos of wire basket & water tank used to determine bulk specific gravity
& absorption of coarse aggregates.
Figure 1: Wire basket & Water tank for experiment No. 7
References
Mamlouk, Michael S., and John P. Zaniewski. Materials for Civil and Construction Engineers.
3rd ed. New Jersey: Pearson, 2011. Print.
Williams, S. (photograph). New York, NY: Bulk specific gravity measurement, 3 May 1978.
UNIVERSITY OF SOUTH ALABAMA
DEPARTMENT OF
Telephone: (251)460-6174
CIVIL ENGINEERING
Facsimile: (251) 461-1400
150 Jaguar Drive, Shelby Hall 3142
http://www.southalabama.edu
Mobile, Alabama 36688-0002
Shenghua Wu, Ph.D., LEED AP.
University of South Alabama
Department of Civil Engineering
Subject: CE 315 Civil Engineering Materials -Lab #2: Gradation Analysis, Fine & Coarse
Aggregates
Dr. Wu,
Sieve analysis is a method utilized in the determination of particle size distribution of aggregates
in a particular sample by dry sieving. Distribution of particle size is very fundamental because
samples are characterized by grain size. This test is used to determine the grading of materials
that are to be used as aggregates for concrete. It ensures that particle size distribution complies
with applicable requirements and provides the data necessary to control the material of various
aggregate products and mixtures. The data may also be useful in developing relationships
concerning porosity and packing. The goal of this experiment is to determine the classification of
the coarse aggregates by ASTM specifications and also to find the fineness modulus of the fine
aggregate.
This experiment was carried out at the civil engineering lab at Shelby Hall on Monday September
11. It was done by the group number 9 whose members are Ali Alshehri, Shadi Alzahrani, and
Cory Judkins. A sample of a dry aggregate with a mass of 10.04 lb was passed through a series
that were arranged progressively by the size of the openings. A pan is placed at the bottom to retain
very particles that pass through all the sieves. The mass of the aggregate that is retained on each
sieve was recorded to calculate percent retained, percent passing & cumulative percent retained
for determination of particle size distribution.
ASTM C33 specifications was used to determine the classification of the aggregates by sieving.
The mass of aggregates that was retained in sieve 2 in, 1.5 in, 1 in, ¾ in, ½ in and the pan was
measured & recorded. The percent retained, percent passing & cumulative percent retained in
each sieve was then calculated.
The sieve gradation analysis experiment was used for grading the fine and coarse aggregate
samples for the use of a concrete mix. Based on the recorded data from dry sieving, the data
showed that the fineness modulus of the fine aggregate was 2.79. Also the data for the coarse
aggregate was classified from ASTM C33 to have a size number 467 which has a nominal size of
1 ½ inches to No. 4. There was loss of fine aggregates do to grains getting stuck in the sieves and
also from transporting the grains to the scale. In addition to aggregates being lost, aggregates
were also gained by the collection of particles that were already in the sieves from previous
experiments. The collection of other particles caused the team an uncertainty of having .6 grams
of excess aggregate in the total. Although there was excess aggregate it did not have a significant
effect on the percent retained, thus making the measurement of the fine aggregates gradation
adequate for the concrete mix.
Thank You
Group 9
References
Standard test method for sieve analysis of fine and coarse aggregates. (2006). West
Conshohocken, PA.
Standard test method for sieve analysis of fine and coarse aggregates. (2001). West
Conshohocken, PA.
Appendix
Appendix A: Data collected from sieve analysis
Table 1: Coarse Aggregate
Dry weight
Sieve size
(in)
10.06 lb.
Weight
pan (lb.)
2
1.5
1
¾
1/2
Pan
11.94
11.86
12.28
12.86
12.38
11.66
Sieve Size
50
37.5
25
19
12.5
mm
mm
mm
mm
mm
(2 in)
(1 1/2 in)
(1 in)
(3/4 in)
(1/2 in)
Loaded
weight
(lb.)
11.94
11.86
13.50
16.26
15.28
14.20
Aggregate
weight
(lb.)
0
0
1.22
3.40
2.90
2.54
Total
Cumulative
mass (lb.)
0
0
1.22
4.62
7.52
10.06
10.06
Amount
Percent
Retained, lb Retained
Percent
Passing Here
100
100
88
54
25
Pan
Total
Table 2: Fine Aggregate
Dry Weight
Sieve size
#4
#8
#16
#30
#50
#100
#200
Pan
Total
499.0 g
Cumulative
mass (g)
3.3
56.0
123.5
263.9
451.6
494.5
498.0
499.6
499.6
0.00
0.00
1.22
3.40
2.90
2.54
10.06
0.00
0.00
12.13
33.80
28.83
25.25
Cumulative
Percent
Retained
Percent
Passing
0.00
0.00
12.13
45.92
74.75
100.00
100.00
100.00
87.87
54.08
25.25
0.00
Sieve Size
4.75
mm
(No. 4)
Percent
Passing Here
99
2.36
1.18
mm
mm
(No. 8)
(No. 16)
0.6
mm
0.3
0.15
0.075
Amount
Percent
Retained, g Retained
Cumulative
Percent Finesse
Percent
Passing Modulus
Retained
3.3
0.7
0.7
99.3
0.01
89
75
52.7
67.5
10.5
13.5
11.2
24.7
88.8
75.3
0.12
0.37
(No. 30)
47
140.4
28.1
52.8
47.2
0.89
mm
mm
(No. 50)
(No. 100)
10
1
187.7
42.9
37.5
8.6
90.3
98.9
9.7
1.1
1.80
2.79
mm
(No. 200)
0
Pan
3.5
1.6
0.7
0.3
99.6
99.9
0.4
0.1
Total
500
Table 3: 0.45 Power Gradation Chart
FHWA 0.45 Power Gradation Chart
100
100
90
89
88
100
99
100
88
80
75
73
70
Percent Passing
64
60
54
50
47
47
40
34
30
25
20
19
14
10
50 mm (2 in)
37.5 mm (1 1/2 in)
25 mm (1 in)
19 mm (3/4 in)
12.5 mm (1/2 in)
9.5 mm (3/8 in)
4.75 mm (No. 4)
2 mm (No. 10)
2.36 mm (No. 8)
1.18 mm (No. 16)
01
0.6 mm (No. 30)
0.075 mm (No. 200)
0.15 mm (No. 100)
0.3 mm (No. 50)
0
10
10.00
0.00
0.075 mm (No. 200)
0
0.15 mm (No. 100)
1
Semilog Gradation Chart
99
50 mm (2 in)
89
37.5 mm (1 1/2 in)
25 mm (1 in)
19 mm (3/4 in)
90.00
4.75 mm (No. 4)
2 mm (No. 10)
2.36 mm (No. 8)
50.00
1.18 mm (No. 16)
0.6 mm (No. 30)
100.00
0.3 mm (No. 50)
Percent Passing
Table 4: Semilog Gradation
100
100
88
80.00
70.00
75
60.00
54
47
40.00
30.00
20.00
25
10
Appendix B: Contributions by each team member
Name of Experiment: Gradation Analysis, Fine & Coarse Aggregates
Date of experiment: 9/11/2017
Lab day and group number: Monday Group 9
Task
Introduction and objective
Description of the experiment
Results
Conclusions
References
Appendix A
Appendix B
Cory Judkins
(Primary Author)
30
40
60
90
10
50
50
Ali Alshehri
Shadi Alzahrani
(Secondary Author)
70
60
40
10
90
50
50
CE 315: Civil Engineering Materials Lab
Group Report Evaluation
Primary Author: _______________________________________
Secondary Author: _____________________________________
Group Number: ____
Lab Name: _____________________________________________________
The report will be evaluated for technical correctness, clarity of explanation, grammar, and spelling.
Maximum Points
Introduction and objective
10
Description of the experiment
15
Results and Discussion
15
Conclusions
15
Citations and References
5
Technical Writing (grammar, paragraph and
sentence structure, technical language, etc.)
30
Subtotal (90 possible)
Appendices Section of the report
A. Data collected during the experiment
4
B. Sample calculations and summary table or
4
tables of all calculations
D. Report of contributions by each team member
2
Subtotal (10 possible)
Grading rubric attached and filled out
-5
Submitted on USA Online and paper copy
-10
Evaluation date
Total
Punctuality at lab (individual to student)
-5
Score
1
UNIVERSITY OF SOUTH ALABAMA
DEPARTMENT OF
CIVIL, COASTAL AND ENVIRONMENTAL
ENGINEERING
150 Jaguar Drive, Shelby Hall 3142
Mobile, Alabama 36688-0002
Telephone: (251) 460-6174
Facsimile: (251) 461-1400
http://www.southalabama.edu
October 10th, 2017
Shenghua Wu
Department of Civil Engineering
University of South Alabama
Subject: CE 315 CE Materials Laboratory – Lab 6: Concrete Batching and Cylinder
Fabrication
Dr.Wu,
Designing or mixing concrete incorporates a number of steps. This is attributable to the
economical, sustainable, durable, and versatility of concrete. Consequently, there is need for
precision and accuracy in steps involved in manufacturing cement; this froths from the need for
high-quality concrete.
A plant that is involved in manufacture of concrete combines ingredients such as air, water,
admixtures, aggregate, silica fume, cement, slag, sand, and fly ash. Henceforth, there is a need to
mix these ingredients with conformance to mass or volume before mixing them. In this light, this
experiment aims to propose a mix design for concrete utilizing ASTM C31. As well, this
experiment puts to perspective a strength of 2500 psi out of which the concrete’s strength will be
tested for 14 days and 28 days strengths. As well, unit weight, slump, and air content will be carried
out.
Batching process in earlier days was mainly done using volume. However, specifications follow
the process follows mass in comparison to volume. Below are percentages of measures for
materials to be used gauging with accuracy.
2
Cement
In a case where cement is more than 30% of size capacity, then its measuring correctness should
be around 1% of necessary mass. However, in a case where it is less than 30% then the accuracy
should be around 4% of necessary quantity.
Aggregates
Should the measurement exceed 30% of scale capacity, measuring accuracy should follow 1%. In
the contrary, the measuring accuracy should be under 3%.
Water
Water should be measured in its appropriate volumetric quantity usually 1kg= 1 liter. In this case,
the accuracy of measurement should be in the range of 1%.
Admixtures
Chemical admixtures may utilize the recommended accuracy for water. On the other hand, mineral
admixtures should follow cement’s. This accuracy measures follow the fact that mineral
admixtures may be used partially to replace cement, while, chemical admixtures are mainly in the
form of liquid hence their accuracy’s kowtow to water’s.
Usually, this process follows stirring or rotation with the objective being coating the surface of
aggregate particles with paste from cement, as well as blinding ingredients into a regular mass.
Thereafter, the concrete is subjected to processes of compaction and placing which are undertaken
simultaneously. These processes are important in ensuring durability, impermeability, and strength
are achieved in the structure of concrete.
This lab was conducted by the use of preliminary calculations found from previous data for the
properties of coarse and fine aggregates. The team began by collecting the required amount of
material and separating them into different buckets. Once all of the materials were collected they
were transported near the mixer. The team checked the mixer to make sure that it was clean and
ready for use. After the inspection the mixer was turned on and shut off after a few revolutions.
Then approximately 1/3 of the volume of water was added to the mixer, and the mixer was turned
on again for a few revolutions. When the mixer was stopped the powder like cement along with
the aggregates and remaining water were added to the mixer, and the mixer was powered back on.
The team let the mixer run for a few minutes to ensure that all of the materials were fully mixed.
3
During the mixing process the team gathered the required apparatus such as molding cone, scoop,
measuring device, base, and tamping rod to perform a slump test. The slump test was performed
by compacting the freshly mixed concrete into the cone and measuring the vertical displacement
of the original height of the concrete to the displaced position of the top of the concrete shown in
figure 2. Also a test was performed to measure the unit weight and air content of the concrete.
After the tests were performed the team added the concrete back to the mixer and ran it to mix the
concrete again. When the concrete was freshly mixed it was scooped, compacted by rodding, and
filled into eight cylinders to make samples. The samples were placed in the lab to cure. Once all
of the procedures were performed the team carefully cleaned out the mixer with regards to the
surrounding environmental area. The team had to return to the lab the following day to strip the
samples and place the concrete into a curing tank for 14 to 28 days.
Based on calculations as shown in Appendix B, the tables following-up are of overall
results, mix design, and batch weight.
Table 1: Results
Air
5%
Slump
3.16 in
Unit weight of concrete
109 lb/ft3
Table 2: Mix Design
Coarse Aggregate
1745.27 lb/cy
Fine Aggregate
1133.89 lb/cy
Water
396.02 lb/cy
Cement
540 lb/cy
Water – Cement ratio
0.65 lb/cy
Air
2%
Table 3: Batch Weight
Coarse Aggregate
39.11 lb
Fine Aggregate
25.41 lb
4
Water
8.87 lb
Cement
12.10 lb
Results highlighted in table 1 were obtained through C143, C231, and C138 ASTM standards.
These were the results for air content, unit weight, and slump of the concrete.
Given that this concrete mix design was based on 2500 psi compressive strength and a 3 inch
slump, the slump obtained was higher than the design. However, after 14 and 28 days, the
fabricated concrete will be tested to test its performance under a load equal or greater than 2500
psi.
5
References
Gaventa, S. (2006). Concrete design. London: Mitchell Beazley in association with Blue Circle.
Mamlouk, M. S., & Zaniewski, J. P. (2011). Portland Cement Concrete. In MATERIALS FOR
CIVIL AND CONSTRUCTION ENGINEERS (3rd ed., pp. 246-313). New Jersey, NJ:
Pearson Education Inc.
Mircea, A.
(2011).
Fabrication
technology-related
cracking
elements. Concrete Solutions 2011. doi:10.1201/b11585-15
of
prestressed
concrete
6
Appendix A
Data collected:
Weight of water bucket: 2.21 lb
Water + Bucket = 11.10 lb
CA Bucket = 2.21 lb
CA + Bucket = 29.52 lb
FA Bucket = 1.58 lb
FA + Bucket = 35.84 lb
Cement Bucket = 1.08 lb
Cement + Bucket = 14.82 lb
Slump = 6.16 in
Weight of Concrete + Air Content Bucket = 43.08 lb
Air = 5%
7
Appendix B
-
Aggregate Data:
Coarse Aggregate
Sp Gr
2.5
𝜆
102.5 lb/cf
ABS
2.46 %
MC
0.1 %
Fine Aggregate
Sp Gr
2.62
FM
2.7
ABS
0.55 %
MC
0.12 %
𝑙𝑏
Fine Aggregate = (6.93)(2.62) (62.4 𝑐𝑓) = 1132.54 lb/cy
W(CA,wet) = 1743.52 lb/cy * (1+0.001) = 1745.27 lb/cy
W(FA,wet) = 1132.54 lb/cy * (1+0.0012) = 1133.89 lb/cy
W(water,adj) = 350 lb/cy – 1743.52 (0.001 – 0.0246) – 1132.54 lb/cy (0.0012 - 0.0055)
= 396.02 lb/cy
-
Batch weights:
𝜋
Total Volume = 4 (4𝑖𝑛)2 (8𝑖𝑛)(8 𝑐𝑦𝑙𝑖𝑛𝑑𝑒𝑟𝑠)(1.3) = 1045.5 in3 = 0.0224 cy
Coarse Aggregate = (1745.27 lb/cy) (0.0224 cy) = 39.11 lb
Fine Aggregate = (1133.89 lb/cy) (0.0224 cy) = 25.41 lb
Cement = (540 lb/cy) (0.0224 cy) = 12.1 lb
Water = (396.02 lb/cy) (0.0224 cy) = 8.87 lb
40.517𝑙𝑏
Unit weight of concrete = 0.372 𝑓𝑡 3 =109 lb/ft3
8
Appendix C: Contributions by each team member
Name of Experiment: – Lab 6: Concrete Batching and Cylinder Fabrication
Date of experiment: 10/04/2017
Lab day and group number: Monday Group 9
Shadi Alzahrani
Task
(Primary Author)
Ali Alshehri
Cory Judkins(Secondary
Author)
Introduction and objective
90
10
Description of the experiment
10
90
Results
80
20
Conclusions
70
30
References
60
40
Appendix A
50
50
Appendix B
50
50
Appendix figures
90
10
9
CE 315: Civil Engineering Materials Lab
Group Report Evaluation
Primary Author: _______________________________________
Secondary Author: _____________________________________
Group Number: ____
Lab Name: _____________________________________________________
The report will be evaluated for technical correctness, clarity of explanation, grammar,
and spelling.
Maximum Points
Introduction and objective
10
Description of the experiment
15
Results and Discussion
15
Conclusions
15
Citations and References
5
Technical Writing (grammar, paragraph and
sentence structure, technical language, etc.)
30
Score
Subtotal (90 possible)
Appendices Section of the report
A. Data collected during the experiment
4
B. Sample calculations and summary table or
tables of all calculations
4
D. Report of contributions by each team member
2
Subtotal (10 possible)
Grading rubric attached and filled out
-5
Submitted on USA Online and paper copy
-10
Evaluation date
Punctuality at lab (individual to student)
Total
-5
10
Appendix: Figures
Figure 1
11
Figure 2
12
Figure 3
13
Figure 4
14
Figure 5
REPORT
1
Shenghua Wu, Ph.D., LEED AP
University of South Alabama
Department of Civil Engineering
Mobile, AL 36688
Subject: Lab 4, 14-day and 21-day Concrete Comprehensive Strength Lab
Introduction
The following lab was conducted to measure the 14 and 21-day comprehensive strength of
cylindrical concrete specimens. The 14-day testing was done on October 16th and the 21-day
testing was conducted one week later on October 23rd. The concrete specimens have been
created two weeks before and been stored in a tub of water at the lab. The compressive test is
only applicable to concrete samples with a weight of 800kg/m3 or more. The process is
conducted by applying a comprehensive axial load to a cylinder while recording the rate until
failure occurs. The comprehensive strength of the tested material is obtained from dividing
the maximum load by the specimen’s cross-sectional area. Another type of compressive test
can be used to determine the modulus of elasticity and Poisson’s ratio of the specimen. The
test measures lateral and longitudinal strains. It also determines stress to strain ratios for any
hardened cylindrical concrete. The value of the modulus of elasticity is expected to be less
than that obtained under rapid load application. The examination team included Ali Alshehri,
Shadi Alzahrani, and Cory Judkins.
Description of the Experiment
The lab was conducted first by removing three cylinder samples from the curing and a towel
used to dry them. The length was determined by taking the average measurement from two
locations of each of the specimen. Similarly, the diameter of the concrete specimen was
measured using pi tape in two locations. The specimen was placed in a clean compression
testing machine that had neoprene caps in their location. During the compression test, the
data collection software was running to record the maximum load/stress. Once the sample
had broken, the maximum load and type of break was determined and recorded for each
REPORT
2
sample. Also, pictures of the breaks were taken for data analysis. After one week, the same
process done for another three cylinder samples and the data was saved and downloaded for
analysis.
Results and Discussion
From the observations of the analyzed fractures it was noticed that the 14-day specimens had
a bigger fracture. This implies that the compressive strength of the specimen was higher at
the 21-day and increases with the curing days. “The results imply that the concrete had
achieved sufficient curing more than those on the 14-day test (National Precast Concrete
Association, 2013).” “Curing can be defined as the process of regulating extent and rate of
moisture loss from a concrete during its hydration (Barger, 2013).” The 14-day specimen in
figure 1 is described as a shear fracture whereby it involves diagonal cracking. Figure 2
displays a cone fracture while Ffigure 3 shows a cone and shear fracture.
The indicated results included three specimens for the 14-day and 21-day break tests. The
coefficient of variation for the 14-day specimen is 4.0278-1 = 0.248 while it is 4.056-1 = 0.246
for the 21-day specimen.
Table 1: the measures of diameter.
Specimen no. 14-day
21-day
1
4.0278
4.056
2
4.0278
4.056
3
4.0278
4.056
Table 2: Values of the peak load/stress
Specimen no. 14-day
21-day
1
56k
54k
2
52k
55k
3
51k
58k
There are two main methods through which the modulus of elasticity can be calculated. The
first technique involves using the secant modulus as referenced in AC318. In this case, Excel
was used to plot the data collected and the best line of fit is obtained. The slope of the line of
fit is the secant modulus. The data that is used is clearly selected. The second approach
involves evaluating the chord modulus as outlined in the standard ASTM C469.
REPORT
3
This can be represented as:
𝐸𝑐ℎ𝑜𝑟𝑑 =
𝑠2 − 𝑠1
𝑝𝑠𝑖
𝑒2 − 0.00005
The obtained modulus of elasticity is then compared to two equations. The equations given
from ACI for normally weight concrete is represented as: Etheoretical = 57000 × √𝑓𝑐 ′ psi.
The second equation is the theoretical modulus of elasticity. From AC318. In this case,
Etheoretical = wc1.5×33× 57000 × √𝑓𝑐 ′ psi. Where is wc is the unit weight. The final step
involves determining the Poisson’s ratio. This is done in accordance with the standard ASTM
C469. The ratio for this is:𝑣 =
∈t2−∈t1
∈2−∈1
(This value is dimensionless)
Conclusions
After conducting the compression test on the 14 and 21-day samples, results show that the
21-day cylinders had a higher compressive strength. Another compressive test using a
compressometer can determine values such as lateral and longitudinal strains. The strains are
used for finding the modulus of elasticity and poisons ratio. Due to deficiency the values
were not found for the samples. The fractures that described the breaks from the specimens
were cone, shear, and both cone and shear. Majority of the samples had a cone fracture.
REPORT
4
References
Barger, E. (2013, October 28). Oliver Tsai. Retrieved October 30, 2017, from
http://precast.org/2013/10/28-day-myth/
National Precast Concrete Association. (2013). National Precast Concrete Association.
Retrieved October 30, 2017, from http://precast.org/why-precast/
REPORT
Appendices
Appendix A: Data that has been collected from the experiment
Figure 1: 14-day specimen 1 break
Figure 2: 21-day specimen 1 break
Figure 3: 21-day specimen 2 break
5
Purchase answer to see full
attachment