investigation of compressive strength of concrete made by different types of aggregate in marine...
TRANSCRIPT
Investigation of Compressive Strength
of Concrete Made by Different Types of Aggregate in Marine
Environment in BangladeshThesis
CE 494 & 495Department of Civil Engineering
Presidency University, Bangladesh
This Thesis is Prepared By
Name Roll No.
Md. Jasim Uddin 121 033 045
Md. Nazmul Hasan 121 035 045
Md. Moinur Rahman Abir 121 037 045
Saifullah 121 120 045
Supervised By
Prof. Dr. Engr. Zahid Hossian Prodhan
ProfessorDepartment of Civil EngineeringPresidency University, Bangladesh
Introduction
Overview In this thesis, we have created 15 cylinders of concrete using
different coarse aggregate; Jaflong, Bholaganj, Dinajpur, Mymensingh & LC (black).
The effect of salt water in concrete cylinders & maximum compressive strength of concrete among different coarse aggregates were studied in this research work.
28 days’ compressive strength was measured to evaluate the result.
Constituent Materials mixing ratio was 1:2:4 & w/c ratio was 0.5. Both mixing & water-cement ratio were kept constant.
Introduction Concrete is one of the major building materials use in modern
day construction. Used for numerous purposes in construction such as the
construction of buildings, dams, foundations, highways, parking structures, pipes, poles among others.
Also, the use of concrete offshore drilling platforms and oil storage tanks is already on the increase.
So, there is a very significance effect of salt water in those concrete structure.
For this, in this thesis, we have compared the maximum strength of concrete using different coarse aggregates in both fresh water & salt water.
Flow ChartMaterial Collection
Bholagonj Mymensingh Dinajpur LC Black Zaflong
Sieve Analysis
Specific Gravity & Absorption Capacity Test (CA)
Specific Gravity & Absorption Capacity Test (FA)
Cylinder Casting & Curing in Salt & Fresh Water
Compressive Strength Test Result
Literature Review
Literature Review
Title: Effect of Seawater for Mixing & Curing on Structural ConcreteAuthor(s): Falah M. Wegian Institute: College of Technological Studies (PAAET), KuwaitYear: 2010
“Concretes mixed and cured in seawater have higher compressive, tensile, flexural and bond strengths than concretes mixed and cured in fresh water in the early ages at 7 and 14 days. The strengths after 28 and 90 days for concrete mixes mixed and cured in fresh water increase in a gradual manner”
Literature Review
Title: Effect of aggregate type on Compressive strength of concreteAuthor(s): Abdullahi. M Institute: Federal University of Technology, NigeriaYear: 2012
“Aggregate type has effect on the compressive strength of normal concrete. Highest compressive strength was achieved from concrete containing crushed quartzite, followed by concrete containing river gravel. Concrete containing crushed granite shows the least strength development at all ages”
Literature Review
Title: Effect of Salt Water on Compressive Strength of ConcreteAuthor(s): Preeti Tiwari, Rajiv Chandak, R.K. YadavInstitute: Jabalpur Engineering College, IndiaYear: 2014
“At 28 days, the rate of strength gain is still increasing in all the concrete cubes. The fresh water cubes also recorded its maximum strength at 28 days. Although, the compressive strength of the salt water concrete cubes was slightly higher than that of the fresh water concrete cubes”
Literature Review
Title: Effect of seawater on compressive strength of concrete cylinders reinforced by non-adhesive wound hybrid polymer compositesAuthor(s): Hsien-Kuang Liu, Nyan-Hwa Taib, Wen-Hung LeeInstitute: Feng-Chia University, TaiwanYear: 2002
“It was observed that concrete cast and cured with seawater increases gradually for all curing days beyond the strength of control cast (FF). The compressive strength of concrete batches FF agrees with the value of the compressive strength of 1:2:4 mix at 28 days, of about 20 N/mm2”
Literature Review
Title: Effect of salt water on compressive strength, water vapor transmission & corrosion of steelAuthor(s): Donald F. Griffin, Robert L. HenryInstitute: U.S Naval Civil Engineering Laboratory, USAYear: 1964
“The effect of sea water on compressive strength of concrete also resulted in some rather unusual curves of strength versus salinity of mixing water. Although there were variations of compressive strength with increased sea-water salinities, there is a general increase in strength of concrete with age and with increasing salinities of mixing water up to about 88 gm/kg”
Compressive Strength (Fresh Water vs Salt Water Curing) Research indicates that seawater is not suitable for the
mixing and curing of both plain and reinforced concrete in marine conditions (Akinkurolere et al. 2007).
However, concrete made with the seawater may have a higher early strength than normal concrete and the reduction in strength with age can be compensated by reducing the water–cement ratio (Shayan et al. 2010).
Naghoj and Abdel-Rahman (2005) reported that adding loam to a concrete mix can increase the compressive strength of the concrete under normal conditions and enhance the performance of hardened concrete to resist the aggressive mediums of salty seawater.
Compressive Strength (Fresh Water vs Salt Water Curing)Mehta (1980) reported after exposing concrete cylinder to sea water that the section of concrete that always remain above high-tide lines would bevulnerable to crackingand spalling as shownby the representationdiagram in Figure 1.
Source: Structural Renovation in Concrete by By Zongjin Li, Christopher Leung, Yunping X.
Compressive Strength (Fresh Water vs Salt Water Curing) Another investigation recently carried out by Portland Cement
Association (PCA) on long time study of cement performance in concrete (LTS) program provides key insights into the performance of concrete in seawater.
The results of their 37-year study revealed that seawater had no damaging effect on submerged concrete specimens, regardless of their cementitious composition; whereas, concrete positioned above high tide suffered more corrosion damage than concrete placed at mean tide levels.
Methodology
Methodology
What is Methodology? Methodology is the systematic, theoretical analysis of the
methods applied to a field of study. It comprises the theoretical analysis of the body of methods and
principles associated with a branch of knowledge. Typically, it encompasses concepts such as paradigm,
theoretical model, phases and quantitative or qualitative techniques.
Methodology
In This Thesis Collecting Constituent Materials
(Portland cement, fine aggregate & coarse aggregate)
Sieve Analysis Specific Gravity & Absorption
Capacity Test Unit Weight Test
Preparation of Concrete Cylinders
Casting of Concrete Cylinders Curing Drying of Concrete Cylinders Testing of Compressive Strength Result
Collecting Constituent Materials
A) L.C. Black B) Dinajpur C) Jaflong
Coarse Aggregates
Collecting Constituent Materials
D) Bholagonj E) Mymensingh Coarse Aggregates
Collecting Constituent Materials
Sylhet sand
Fine Aggregates Portland Cement
OPC 43 grade
Sieve Analysis
Sieve analysis helps to
determine the particle
size distribution
of the coarse
aggregates
Specific Gravity & Absorption Capacity Test Wt. of S.S.D Sample in Air, B (gm) Wt. of S.S.D Sample in Water. C (gm) Wt. of O.D Sample in Air, A (gm)
Now Apparent Specific Gravity = A/(A-C) Bulk Specific Gravity (S.S.D) = B/(B-C) Bulk Specific Gravity (O.D) = A/(B-C) Absorption Capacity, D% = (B-A) * 100/A
Data
Result
Specific Gravity & Absorption Capacity Test
A) SSD Wt. Air B) SSD Wt. Water C) Oven Dry
Unit Weight Test By unit weight test, we can find the weight per unit volume of CA
or FA
A) Rodding B) Shaking C) Shoveling
Preparation of Concrete Cylinders
Mobil was used as lubricating oil to
wipe the inside of the molds for
easily remove after hardening of
the concrete.
Casting of Concrete Cylinders
The casting was done at SM lab of Presidency University, Bangladesh. All stones were cast in the different cylinder by the proportion of 1:2:4. After casting we submerged that cylinder in water drum for 24 hours.
A) Casting B) Labeling
Curing
3.5% salt was mixed in water to make marine environment water.
Cylinders were kept submerged as long as for 28 days.
A) Adding Salt B) Curing
Drying of Concrete Cylinders After withdrawal from the drum, drying in the open place for 24
hours.
Drying of cylinders
Testing of Compressive Strength
The compressive strength test was performed on the concrete cylinder, tested at the curing age of 28 days using the compression testing machine.
The cylinder was placed between the compressive plates parallel to the surface and then compressed at a uniform rate (without shock) until failure occurred.
The max load at failure and the compressive strength were read through of the screen at the top of the machine.
The compressive strength was calculated by dividing the maximum load in Newtons (N) by the average cross-sectional area of the specimen in square millimeter (mm2)
Testing of Compressive Strength
Compressive Strength Test
Result & Discussion
Result Result of Fineness Modulus of Coarse Aggregates
Bholag
onj
LC Blac
kJafl
ong
Mymen
singh
Dinajpu
r0
0.5
1
1.5
2
2.5
3 Type of Aggregates
FM
Bholagonj 2.279
LC Black 2.266
Jaflong 2.218
Mymensingh 2.435
Dinajpur 2.017
Result Result of Apparent Specific Gravity & Absorption Capacity of
Coarse AggregatesType of
Aggregates
Apparent Specific Gravity
Absorption Capacity
(%)Bholago
nj3.06 4.43
LC Black 2.94 4.52
Jaflong 2.78 3.63
Mymensingh
2.96 4.60
Dinajpur 2.92 4.06
Bholag
onj
LC Blac
kJafl
ong
Mymen
singh
Dinajpu
r012345
Apparent Specific GravityAbsorption Capacity (%)
Result Result of SSD & OD of Coarse Aggregates
Name SSD (gm) OD (gm)
Bholagonj
2.82 2.70
Jaflong 2.62 2.53
Mymensingh
2.72 2.60
Dinajpur 2.71 2.61
LC Black 2.71 2.57Bho
lagon
j
Jaflon
g
Mymen
singh
Dinajpu
r
LC Blac
k2.35
2.45
2.55
2.65
2.75
2.85
SSD (gm) OD (gm)
Result Result of Unit Weight & % Void of Coarse Aggregates
Bholag
onj
LC Blac
kJafl
ong
Mymen
singh
Dinajpu
r020406080
100120
Unit Weight (lb/cft) % Void
Type of Aggreg
ates
Unit Weight (lb/cft)
% Void
Bholagonj
97.75 41.98
LC Black
101.05 37.48
Jaflong 96.12 39.12
Mymensingh
100.31 38.17
Dinajpur
100.91 38.04
Result Result of Compressive Strength of Concrete for Different Types
Coarse Aggregates
Name Mix Propertie
s
W/C Avg. Compressive
Strength (Fresh Water)
(psi)
Avg. Compressive
Strength (Salt Water)
(psi)Bholagonj 1:2:4 0.5 3602.548 3994.904
Jaflong 1:2:4 0.5 4173.248 4458.599
Mymensingh 1:2:4 0.5 3031.847 3210.191
Dinajpur 1:2:4 0.5 3103.185 3210.191
LC Black 1:2:4 0.5 4280.255 4494.268
Result of Compressive Strength of Concrete for Different Types Coarse Aggregates
Bholagonj Jaflong Mymensingh Dinajpur LC Black0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
Avg. Compressive Strength (Fresh Water) (psi)Avg. Compressive Strength (Salt Water) (psi)
Failure Pattern of Concrete Cylinder
(a) Cone & Shear (b) Columnar (c) Columnar
Cylinders: (a) Bholagonj (b) LC Black (c) Mymensingh
Failure Pattern of Concrete Cylinder
(d) Columnar (e) Shear
Cylinders: (d) Jaflong (e) Dinajpur
Discussions To compare the Compressive Strength of Concrete made by
different types of aggregate, we got highest in both fresh water & salt water for LC (Black) coarse aggregate and lowest for Mymensingh coarse aggregate.
Also, we have found that there was a marginal increase in the of concrete cylinders which were cast and cured with salt water as compared with the concrete cylinders cast and cured with fresh water.
The rate of the strength gain in fresh water cylinders is slow as compared with the salt water cylinders.
Strengths are also affected by the aggregate type, properties, cement type, age and curing conditions but with a lower rate than the effect of cement content.
Conclusions & Recommendations
Conclusions From our experimental study, we have found
that the LC (Black) coarse aggregate was better than the others coarse aggregate.
Also, we can conclude that there is no reduction in the strength if we use salt water casting and curing the concrete. There is some increase in the strength if salt water is used for casting and curing. This concrete can be used for mass concreting without any decrease in strength properties.
Recommendations The use of salt water should be welcomed and not feared
for casting and curing of concrete during construction most especially in the coastal environment.
Water/Cement ratio that will give the minimum value of slump with adequate workability, as well as minimum cement content, should be used with maximum aggregate size in order to minimize the shrinkage cracking.
Mix ratio was constant in this study research should be revised for different mix ratio.
With the increases of the aggregate size required water cement ratio lower. So, this study should be conducted with the different water-cement ratio.
Recommendations
This study should perform for coarse aggregate and it is necessary to prepare standard grading requirement for both fine and coarse aggregate (stone).
Further study should be made on prevention of reinforcement from sulfate attack in order to avoid the fear of reinforcement from being easily corroded and on the effect of salt water on other important characteristics of concrete.
Thanks To All
Q & A