STUDY ON PREDICTION OF MECHANICAL PROPERTIES OF LARGE RING-SHAPED FORGING DEP...
FINAL DEFENSE CDC
1. Effect of Aggregate Types on Reinforced
Concrete Slab Exposed to Elevated
Temperatures
by
Clariza D. Cerezo
Bachelor of Science in Civil Engineering
Mapúa Institute of Technology, 2010
Master of Science in Civil Engineering
Major in Structural Engineering
June 16, 2014
Adviser: Engr. Jocelyn Buluran
2. Flow of Presentation
1. Previous Recommendations
2. Frameworks – Theoretical and Conceptual
3. Statement of the Problem
4. Specific Objectives
5. Significance of the Study
6. Scope and Limitations
7. Methodology
8. Results and Discussion
9. Conclusion
10. Recommendations
3. Previous Recommendations
• Carbonate Rocks (Gravel)
• LJV Construction Materials
• Siliceous Rocs (Pebbles)
• Arstone Trading
Supplier of
Aggregates
• Physical (Quality) Test
• Terms Testing Center
• Chemical Test
• not performed; not available in Philippines
• Supported only with researched information
Aggregates to be
tested for chemical
and physical
properties
4. Theoretical Framework
Properties Principle / Theory Description Reference
Mechanical Properties of Steel affected in Elevated Temperature
Tensile Strength Decreases while temperature
increases
The maximum stress that a
material can withstand while
being stretched or pulled before
failing or breaking.
Erdem (2009)
Modulus of
Elasticity
Decreases while temperature
increases
The modulus of elasticity of
reinforcing steel also decreases
Harmathy, 1993
Deformation of
Steel
Increases while temperature
increases
Thermal strain, creep strain and
stress related strain comprises of
total strain which is the property
of steel when it deforms at
elevated temperatures
Thermal strain:
EC (1995) and
Anderberg (1983)
Creep Strain:
Kirby and Preston
(1988)
Stress Related
Strain:
Harmathy (1993)
5. Theoretical Framework
Properties Principle / Theory Description Reference
Mechanical Properties of Concrete affected in Elevated Temperature
Compressive
strength of
Concrete
Decreases while temperature
increases
the compressive strengths of
concrete at elevated
temperatures are related to
aggregates and stress levels
Bažant et al., 1996
Deformation of
concrete
Increases while temperature
increases
the total deformation of concrete
is composed of the thermal
strain, the stress-related strain,
the creep strain, and the
transient strain
Buchanan (2002)
6. Theoretical Framework
Properties Principle / Theory Description Reference
Thermal Properties of Steel affected in Elevated Temperature
Thermal
Conductivity
Decreases while temperature
increases
is defined as the ratio of heat flux
to the temperature gradient and
is used to measure the ability of
a material to conduct heat
EC3, 1995
Specific Heat Increases while temperature
increases
determines the heat absorption
capacity of a material for a given
rise in temperature
EC3, 1995
Thermal Properties of Concrete affected in Elevated Temperature
Thermal
Conductivity
Decreases while temperature
increases
depends on the type of
aggregates used in the mixture,
porosity, moisture content, and
the range of temperature it is
exposed to
Lie (1992)
Specific Heat Increases while temperature
increases
the only parameter that concerns
the specific heat of concrete is its
moisture content
Lei, 1992
9. Objectives
• Observe on the changes to the slab members exposed to different
temperatures according to ASTM E119.
• Compare and check the mechanical properties of the heated slabs
to that of the temperate slabs.
• Present the effect of using different aggregates in the concrete
mixture and different types of cooling method after heat testing.
10. Significance of the Study
• The loss of lives due to structural failure during the misfortunate
event will be prevented by studying and developing effective design
of reinforced concrete slab in elevated temperature
• Theoretical and experimental amount of strength reduction of RC
slabs composed of different aggregates, will be presented
• Develop statistical analysis of mechanical capacity of the member
after fire exposure
• Decrease in renovation cost can also be attained, when only after
tested, the member presents capabilities near to the capacity of
normal slabs.
11. Scope and Limitations
Scope
• Prepare specimens according to standard codes
• Different types of aggregates: carbonate and siliceous.
• Heat the specimens in 200, 400 and 600 degrees Celsius for one
and half hours each.
• Compare the flexural strength of the heated slabs to the base
samples.
• This study will use the locally available materials here in the
Philippines
• There will be three specimens per concrete base configuration.
12. Scope and Limitations
Changes of variables from Previous Scope
Mixing and Pouring of
Concrete using:
•Shale Aggregates
•Carbonate Aggregates
•Siliceous Aggregates
Mixing and Pouring of
Concrete using:
•Siliceous Aggregates
•Carbonate Aggregates
Heat Samples to the
temperatures:
•200 Degrees Celsius
•400 Degrees Celsius
•600 Degrees Celsius
Heat Samples to the
temperatures:
•300 Degrees Celsius
•600 Degrees Celsius
•900 Degrees Celsius
13. Scope and Limitations
Limitations
• Full scaled samples could not be handled due to lack of testing
equipment in the Philippines
• Certain number of samples only used due to financial insufficiency
• Degree and duration of heating is determined via previous studies
• Connections and bond strength to other structural members have
not been studied here
• Shear is not also analyzed here
14. This study will answer the following specific questions :
Specific Problem
(1.) What are the physical effects on the specimens after being
exposed to high temperatures?
(2.) In what level of temperatures (200-,400-, and 600oC) will
cause higher and lower flexural strength as per method of
cooling and aggregate types
15. This study will answer the following specific questions :
Specific Problem
(3.) Will there be any relationship with the type of aggregates to
be used and the method of cooling to the flexural strength of slab
members?
(4.) If so, which type of aggregate is more suitable for fire design
of reinforced concrete?
16. Methodology
Respondent of the Study
Research Setting
The preparatory works of this study was done in a vacant lot in BF
Homes, Paranaque City. After being cured for 28 days, the
researcher has transferred the specimens to Mapua Institute of
Technology. Here the specimens were tested under high
temperatures as indicated in the scope of the researcher.
17. Methodology
Data Gathering Materials
300mm by 300mm by 100mm slab sizes
Reinforcement configurations
- Each span: 2- 10mm diameter
Concrete Mixture
- 1:2:3:2 (cement: fine: coarse: water)
Cement ASTMC150
Coarse Aggregates
ASTMC33 /
ASTMC127
Fine Aggregates ASTMC128
Reinforcing Steel ASTM496-97a
Preparation and Adequacy validation of
concrete mixture with curing
ASTMC172-92 &
ASTM31C/31M
Design of Specimens (Direct Method) ACI 318-05
Slump Test (workability)
ASTMC143/
143M
Heating and Cooling ASTME119
Flexural Test ASTMC78
Compression Test ASTMC39
Preparation of Samples
Procedures and Tests
18. Methodology
Data Gathering Materials
Sand Gravel
Gray
Pebbles
White
Pebbles
2.275 2.846 2.809 2.629
6.77 1.52 0.39 0.05
inch mm
1" 25 PASS PASS PASS
3/4" 19 PASS PASS PASS
1/2" 12.5 FAIL FAIL FAIL
3/8" 9.5 FAIL FAIL FAIL FAIL
#4 4.75 FAIL FAIL FAIL FAIL
#8 2.36 FAIL FAIL FAIL FAIL
#10 2
#16 1.18 PASS
#30 0.6 PASS
#40 0.425
#50 0.3 PASS
#60 0.249
#100 0.15 FAIL
#200 0.075
Aggregates
Quality Test
Specific Gravity
Absorption %
Sieve Size Cummulitive Percent Passing vs.
Standards (Remarks)
Siliceous
Carbonate
Summary of Quality Test of Aggregates
20. Methodology
Data Gathering Procedures
Preparation of Concrete Mixture
Formworks Concrete mix Slump Test Placing Reinforcement
Concrete Pouring Removal of Forms Curing-
Polyethylene sheets
Transfer of Samples
21. Methodology
Compression Test of Cylinders
Carbonate Rocks
Siliceous Rocks
Compressive
test
Diameter Height Max_Force Max_Stress
Units mm mm kN Gpa (kN/mm2)
GR-1 150 305 380.94 0.02103
GR-2 150 305 390.25 0.02165
GR-3 150 305 380.44 0.02109
PB-1 150 305 373.66 0.02077
PB-2 150 305 365.77 0.02065
PB-3 150 305 371.55 0.02097
29. Data Analysis
Regression line and T-test
• Regression Line and T-test were used in the statistical method to
see the effect in the strength of the samples subjected to different
degree of heat and method of cooling.
• In this research, regression analysis was used as two quantifiable
variables were available: temperature and flexural strength of the
specimens.
41. Data Analysis
Results of Statistical Computations
• The graphical representation of the regression lines all decreases in
strength as temperature increases.
• This can be attributed with the effect of temperature to the samples’ mechanical
and thermal properties, such as the mechanical strength and thermal
conductivity.
• No significant difference- sudden cooling of carbonate rocks and the
gradual cooling of siliceous rocks.
– actual t < critical t
• Significant Difference –gradual cooling of carbonate rocks and
sudden cooling of siliceous rocks
– actual t > critical t; thus reject null hypothesis
42. Data Analysis
Results of Statistical Computations
Mean
Temperature
(o
C)
Gradually
Cooled
Carbonates
Suddenly
Cooled
Carbonates
Gradually
Cooled
Siliceous
Suddenly
Cooled
Siliceous
200 2.19 2.44 2.02 1.79
400 1.47 1.48 1.64 1.48
600 1.74 1.42 1.34 1.46
Mean Stress Mpa
43. Data Analysis
Results of Statistical Computations
Same Aggregate Types different Cooling Method
0.00
0.50
1.00
1.50
2.00
2.50
3.00
200 400 600
StressMPa
Temperature ˚C
Gradually Cooled
Carbonates
Suddenly Cooled
Carbonates
0.00
0.50
1.00
1.50
2.00
2.50
200 400 600
StressMPa
Temperature ˚C
Gradually Cooled
Siliceous
Suddenly Cooled
Siliceous
44. Data Analysis
Results of Statistical Computations
Same Cooling Method different Aggregate Types
0.00
0.50
1.00
1.50
2.00
2.50
200 400 600
StressMPa
Temperature ˚C
Gradually Cooled
Carbonates
Gradually Cooled
Siliceous
0.00
0.50
1.00
1.50
2.00
2.50
3.00
200 400 600
StressMPa
Temperature ˚C
Suddenly Cooled
Carbonates
Suddenly Cooled
Siliceous
45. Data Analysis
Results of Statistical Computations
0.00
0.50
1.00
1.50
2.00
2.50
200 400 600
StressMPa
Temperature ˚C
Gradually Cooled
Carbonates
According to Zhang’s study, there’s a
slight decrease to Young module, where
stiffness again increases in the
temperature range of 400 to 600˚C and
then decreases again.
46. Conclusion
The effect of aggregates and cooling method on reinforced concrete
slabs exposed to elevated temperatures were tested and analyzed.
Materials that are readily available in the local market which has
passed ASTM standards were mainly used in preparation and
testing of the samples.
Regression line and two tailed T-test were used in the statistical
analysis and through the scattered diagrams regression lines all
decreases in strength as temperature increases.
Further Conclusion will answer the Specific Problems and then give
economical analysis of the importance of this study
47. This study will answer the following specific questions :
Specific Problem
(1.) What are the physical effects
on the specimens after being
exposed to high temperatures?
-Color changes to light brown as
temperature increases
-Small cracks at surfaces mostly
for siliceous rocks
48. This study will answer the following specific questions :
Specific Problem
(2.) In what level of temperatures (200-,400-, and 600oC) will
cause higher and lower flexural strength as per method of cooling
and aggregate types Stress (Mpa) Temperature Type
Highest Stress 2.44 200 Sudden
Lowest Stress 1.42 600 Sudden
Highest Stress 2.02 200 Gradual
Lowest Stress 1.34 600 Gradual
Highest Stress 2.19 200 Carbonates
Lowest Stress 1.34 600 Siliceous
Highest Stress 2.44 200 Carbonates
Lowest Stress 1.42 600 Carbonates
Carbonate Rocks
Siliceous Rocks
Gradually Cooled
Suddenly Cooled
49. This study will answer the following specific questions :
Specific Problem
(3.) Will there be any relationship with the type of aggregates to
be used and the method of cooling to the flexural strength of slab
members?
No significant difference- sudden cooling of carbonate rocks and
the gradual cooling of siliceous rocks.
actual t < critical t
Significant Difference –gradual cooling of carbonate rocks and
sudden cooling of siliceous rocks
actual t > critical t; thus reject null hypothesis
50. This study will answer the following specific questions :
Specific Problem
(4.) If so, which type of aggregate is more suitable for fire design
of reinforced concrete?
Temperature
(o
C)
Stress (MPa)
200 2.9100
200 2.0900
200 2.3200
400 1.6600
400 1.3900
400 1.3900
600 1.0800
600 1.9500
600 1.2400
r -0.7445
actual t -2.9503
critical t -2.3646
β0 -0.0025
β1 2.7978
α 0.0500
2.Sudden Cooling
(Carbonate Rocks)
51. Economical Analysis
Type of Aggregates used:
Pebbles are 18 to 63% more costly than Gravel.
However shows slightly higher flexural strength than carbonates when gradually
cooled after exposure to 400˚C and suddenly cooled after exposed to 600˚C.
Renovation vs. Restoration
Less cost than restoration
Temperature
(o
C)
Gradually
Cooled
Carbonates
Suddenly
Cooled
Carbonates
Gradually
Cooled
Siliceous
Suddenly
Cooled
Siliceous
200 2.19 2.44 2.02 1.79
400 1.47 1.48 1.64 1.48
600 1.74 1.42 1.34 1.46
Mean Stress Mpa
52. Economical Analysis
Renovation vs. Restoration
Less cost than restoration
Table shows the
percentage decrease
in strength
Temperature (˚C)
Gradually
Cooled
Carbonates
Suddenly
Cooled
Carbonates
Gradually
Cooled
Siliceous
Suddenly
Cooled
Siliceous
Room Temp.
200 2.19 2.44 2.02 1.79
400 1.47 1.48 1.64 1.48
600 1.74 1.42 1.34 1.46
200 0.90 0.65 0.59 0.81
400 1.61 1.61 0.97 1.13
600 1.35 1.66 1.27 1.15
200 29% 21% 23% 31%
400 52% 52% 37% 43%
600 44% 54% 49% 44%
3.09 2.61
Difference in Strength vs. Base Samples
Percentage Decrease in Strength vs Base Samples
Mean Stress Mpa
53. Recommendation
• The researcher has only presented two types of rocks; further
studies can be performed for other types but perhaps with different
concrete mixture and chemically tested aggregates.
• Different types of cooling such as different lubricants may be used
and that may perhaps offer a more favorable result.
• Thorough investigation can be done with different configuration and
design of samples.
• It is encourage that additional study be conducted on higher degree
of temperature as changes to reinforcements will only be seen once
reached 800 degrees above.
54. References
• American Society for Testing and Materials (2002). Standard
Practice for Making and Curing Concrete Test Specimens in the
Laboratory, ASTM C 192/C 192 M-02, Pennsylvania, USA
• American Society for Testing and Materials (2002). Standard Test
Method for Sieve Analysis of Fine and Coarse Aggregates , ASTM C
136, Pennsylvania, USA
• American Society for Testing and Materials (2002). Sheet Materials
for Curing Concrete, ASTM C 171, Pennsylvania, USA
• American Society for Testing and Materials (2001). Standard
Specification for Compressive Strength of Cylindrical Concrete
Specimens, ASTM C 39/C 39 M-01, Pennsylvania, USA
• American Society for Testing and Materials (1997). Standard Test
Method for Bulk Density (“Unit weight”) and Voids in Aggregate,
ASTM C 29/C 29M-97, Pennsylvania, USA
55. References
• American Society for Testing and Materials (2001). Standard
Practice for Making and Curing Concrete Test Specimens in the
Field, ASTM C 31/ C 31M-01, Pennsylvania, USA
• American Society for Testing and Materials (2002). Standard
Specification Concrete Aggregates, ASTM C 33-02, Pennsylvania,
USA
• American Society for Testing and Materials (2000). Standard
Terminology Relating to Concrete and Concrete Aggregates, ASTM
C 125-00, Pennsylvania, USA
• American Society for Testing and Materials (2001). Standard Test
Method for Density, Relative Density (Specific Gravity), and
Absorption of Coarse Aggregate, ASTM C 127-01, Pennsylvania,
USA
56. References
• American Society for Testing and Materials (2001). Standard Test
Method for Density, Relative Density (Specific Gravity), and
Absorption of Fine Aggregate, ASTM C 128-01, Pennsylvania, USA
• American Society for Testing and Materials (2001). Standard Test
Method for Sieve Analysis of Fine and Coarse Aggregates, ASTM C
136-01, Pennsylvania, USA
• American Society for Testing and Materials (2000). Standard Test
Method for Slump of Hydraulic-Cement Concrete, ASTM C 143/C
143M-00, Pennsylvania, USA
57. References
• American Society for Testing and Materials (2002). Standard
Specification for Portland Cement, ASTM C 150-02, Pennsylvania,
USA
• American Society for Testing and Materials (1999). Standard
Specification for Sampling Freshly Mixed Concrete, ASTM C 172-
99, Pennsylvania, USA
• Cuntapay, E. (2004). National Building Code of the Philippines.
• Association of Structural Engineers of the Philippines (2010).
National Structural Code of the Philippines 2010, 6th Edition,
Association of Structural Engineers of the Philippines, Inc., Quezon
City, Philippines.
• Walpole, R.E., R.H. Myers, S.L. Myers, and K. Ye (2012). Probability
and Statistics for Engineers and Scientists, 9th Edition, Prentice
Hall, USA
