Final Presentation 24-5-08
description
Transcript of Final Presentation 24-5-08
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DESIGN OF HIGH PERFORMANCE CONCRETE (HPC) MIXTURE IN
AGRESSIGE ENVIRONMENT
United Arab Emirates University College of Engineering
Civil and Environmental Engineering Department
Graduation Project II
Prepared by:Saeed Khamis Al Haddadi 200203853
Nayel Rashid Al Shamsi 200216968
Mansour Mohd Al Shebli 200204979
Saeed Nahyan Al Ameri 200204458
Muath Mohd Al Mazrooei 200205340
Dr. Amr S. El Dieb
2st Semester 2007/2008
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Objective
Mix Design Methods
Experiment and Testing
Gant Chart
Introduction
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HPC is defined as concrete which meets special
performance and uniformity requirements that cannot
always be achieved by using only the conventional
materials
Concrete is composed principally of aggregates, Portland
cements, water, and may contain other cementations
materials and/or chemical admixtures.
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The selection of concrete proportions involves a balance between economy and requirements for place ability, strength, durability, and density (i.e. its performance).
HPC is characterized by its high performance in any of its properties or characteristics
Usually the term HPC is used to define high durable concrete (i.e. concrete characterized by high durability)
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The required durability characteristics are governed by the application of concrete and by conditions expected to be encountered at the time of placement. These characteristics should be listed in the job specifications.
Impact
Concrete Environment Deterioration
Impact
Resistance Concrete Environment
Durable
Concrete
(HPC)
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The effect of different SCM with various dosages on
HPC mixes will be evaluated for various aggressive
environments.
Different concrete mix design methods will be
implemented and compared to design HPC mixes.
Control concrete mix will be designed having a
compressive strength of 40 to 50 MPa, slump between
100 120 mm and the cement content is 350 kg/m3.
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There are two well known mix design
methods implemented by various codes :
BS 8328 mix design method.
ACI 211.1-91 mix design method.
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To perform a concrete mix design several criteria (i.e
inputs) are needed together with the properties of the used
materials
The criteria needed includes:
Required strength
Required slump
Minimum cement content
Properties of available or used materials; investigated in
GPI
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BS Method
Approximate compressive strength (N/mm2) of concrete mixes
made with a free water/cement ratio 0.5
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BS Method..
Relationship between
compressive strength
and free water-/cement
ratio
From this graph w/c
ratio is determined for
the required strength
47
0.47
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BS Method
Approximate free water content (Kg/m3) required to give
various levels of workability.
Slump is adjusted by admixture dosage
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BS Method
Estimated wet density
of fully compacted
concrete to calculate
the aggregate quantity
170
2420
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BS Method
Determines the mixing ratio of fine and coarse aggregates
depending on the grading zone of the fine aggregate (1,2,3 &4)
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35%
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Relationship between water-cement or water- cementations
materials ratio and compressive strength of concrete
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Approximate mixing water and air content requirements for
different slumps and nominal maximum sizes of aggregates
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ACI Method
Volume of coarse aggregate per unit of volume of concrete
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Discussion
After we used two methods we found ACI method is not
appropriate to design our control mix because the maximum
strength we can design using this method is 34 MPa and it is
using cylinder not cube so BS method is used.
incorporation of supplementary materials such as Slag and
Silica fume.
Typical concrete mix used in the country is designed using
material investigated in GPI.
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Criteria for mix design
Parameters:
Silica fume
Slag
Combination of silica fume and slag
Many ready mix company in my country used silica fume in range of 8% and slag in range of 40% to 60% of cement content.
We will use 5% , 8%, and 15% of silica fume to make comparison between it.
Also we will used 25%,40% and 60% of slag to compare between it.
In addition, we will study the ternary blends ( silica fume and slag ).
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Strength 40-50 MPa
Slump 100-
C.C. at least 350 kg/m3
Cement Sand
Dune
sand
C.Agg.(S2-
20mm) C.Agg.(S1-10mm) Water Slag
Silica
Fume Admixtures
22.4 35.5 11.9 50.5 21.3 10.6 0 0 Variable
Cement Sand
Dune
sand
C.Agg.(S2-
20mm)
C.Agg.(S1-
10mm)
Water cement
ratio Water Slag
Silica
Fume Admixtures
350 555 186 790 333 0.47 166 0 0 Variable
Batch Quantities
Mix Proportions/ m3
Criteria for mix design
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EXPERMINT AND TESTING
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SCM
SCM usually works in two ways:
As microfilling materials i.e. physical effect (in early stages)
Pozzolanic materials (in late stages)
Microfilling Effect
(Physical effect)
Introduction
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Pozzolanic Reaction
SCM in finely divided form provides a source of
reactive silica that in the presence of moisture will
combine with CH to form C-S-H and other
cementing.
Typically slow down hydration, but significantly
improve durability and long-term strength
Introduction
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Pozzolanic Reaction
2C3S + 6H C-S-H + 3CH
2C2S + 4H C-S-H + CH
CH + SCM + H C-S-H
Introduction
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Hydration of C3S & C2S
C-S-H
CH
Introduction
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Result of the reduction of high-purity
quartz with coal in an electric arc
furnace in the manufacture of silicon
or ferrosilicon alloy.
Have large surface area
Silica Fume
SCM Material
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Slag
Made from iron blast-furnace slag.
It is a non-metallic hydraulic cement consisting essentially of
silicates and alumino-silicates of calcium.
SCM Material
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Total
Quantities
C1 C1-SF5 C1-SF8 C1-SF15 C1-S25 C1-S40 C1-S60 C1-S25-SF5 C1-S25-SF8 C1-S40SF5 for all Mixes
Cement kg 22.4 21.3 20.6 19.0 16.8 13.4 9.0 15.7 15.0 12.3 166
Sand kg 35.5 35.4 35.3 35.1 35.4 35.3 35.2 35.3 35.3 35.3 353
Dune Sand kg 11.9 11.8 11.8 11.8 11.8 11.8 11.8 11.8 11.8 11.8 118
C.Agg.(S2-20mm) kg 50.5 50.4 50.3 50.0 50.4 50.2 50.1 50.3 50.3 50.2 503
C.Agg.(S1-10mm) kg 21.3 21.2 21.2 21.1 21.2 21.2 21.1 21.2 21.2 21.1 212
Water lit 10.6 10.6 10.6 10.6 10.6 10.6 10.6 10.6 10.6 10.6 106
Slag kg 0.0 0.0 0.0 0.0 5.6 9.0 13.4 5.6 5.6 9.0 48
Silica Fume kg 0.0 1.1 1.8 3.4 0.0 0.0 0.0 1.1 1.8 1.1 10
Admixtures kg To be adjusted to maintain a constant slump of 100-120mm
Batch Quantities
Mixes
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Mix name C1 C1-SF5 C1-SF8 C1-SF15 C1-S25 C1-S40 C1-S60
C1-S25-
SF5
C1-S25-
SF8
C1-S40-
SF5
Mix date Mon 18/2 Tu 19/2 Th 21/2 Mo 25/2 Tu 26/2 Th 28/2 Mo 3/3 Tu 4/3 Th 6/3 Mo 10/3
Batching Strategy
Lab strategy
Table 4.2.1
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Lab strategy
Testing Strategy
Table 4.2.2
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Laboratory
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Laboratory
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Laboratory
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Laboratory
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Laboratory
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We did four type of tests which are:
Compressive Strength (Cube Test):
Normal compressive strength
Compressive Strength in Sulfate Solution
Tensile Strength.
Sorptivity Test.
Resistivity Test
Testing
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10 cm
10 cm
Normal compressive strength
Compressive Strength
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Figure 5.4: Compressive strength at 7, 28 and 56 days for different dosage of silica
fume
Normal compressive strength
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Figure 5.5: Compressive strength at 7, 28 and 56 days for mixes with different dosage of slag
Normal compressive strength
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Figure 5.6: Compressive strength at 7, 28 and 56 days for mixes
combination with slag and silica fume in different dosage.
Normal compressive strength
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Compressive strength in sulfate
solution
100 Liter with 5% NaSO4 Water heater
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Compressive strength in sulfate solution
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Silica fume effect:
Table 5.3.1.1: Test results for different percentage of SF
Compressive strength in sulfate solution
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Figure 5.7: Effect of sulfate solution on cube strength in ambient temperature for mixes
with different SF dosage
Silica fume effect:
Compressive strength in sulfate solution
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Figure 5.8: Effect of high temperature sulfate solution on cube strength for mixes with
different dosage of SF
Silica fume effect:
Compressive strength in sulfate solution
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Table 5.3.1.2: Reduction in strength at different immersion periods for different
percentages of Silica Fume
Silica fume effect:
Compressive strength in sulfate solution
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Figure 5.9:
Difference in strength
between hot results
and ambient for differ
percentages of SF in
sulfate solution
Silica fume effect:
Compressive strength in sulfate solution
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Slag effect:
Table 5.3.2.1: Test results for different percentage of Slag
Compressive strength in sulfate solution
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Compressive strength in sulfate solution
Slag effect:
Figure 5.10: Effect of ambient temperature sulfate exposure on mixes
with different Slag contents
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Compressive strength in sulfate solution
Slag effect:
Figure 5.11: Effect of high temperature sulfate exposure on mixes
with different Slag contents
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Compressive strength in sulfate solution
Slag effect:
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Compressive strength in sulfate solution
Figure 5.12: Difference in strength between hot results and ambient for differ
percentages of Slag in sulfate solution
Slag effect:
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Compressive strength in sulfate solution
Combined slag & silica fume:
Table 5.3.3.1: Test results for different percentage of Slag and Silica Fume
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Compressive strength in sulfate solution
Combined slag & silica fume:
Figure 5.13: Effect of high temperature sulfate exposure on mixes with
combined slag and silica fume with different contents
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Compressive strength in sulfate solution
Combined slag & silica fume:
Figure 5.14: Effect of ambient temperature sulfate exposure on mixes with
different Slag and Silica Fume contents
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Compressive strength in sulfate solution
Combined slag & silica fume:
Table 5.3.3.2: Reduction in compressive strength for combined slag and silica
fume mixes in sulfate solution.
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Compressive strength in sulfate solution
Combined slag & silica fume:
Figure 5.15: Difference in strength between hot results and ambient for
differ percentages of Slag and Silica Fume in sulfate solution
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Compressive strength in sulfate solution
Strength Reduction:
Table 5.3.4.1: Reduction in compressive strength for combined slag and
silica fume mixes in sulfate solution
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Compressive strength in sulfate solution
Strength Reduction:
Figure 16: Strength reduction at 56 age
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Tensile strength
10 cm
20 cm
2*Failure Load (N)
*200*100 Ft =
Splitting tensile Strength
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Tensile strength
Table 5.4.1: Test results at 7 & 28 days of age
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Tensile strength
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
Ten
sil
e S
tren
gth
(M
pa)
C1 C1-SF5 C1-SF8 C1-SF15
Mixes Name
Split Strength in Difference Ages in Slica Fume
7 Days
28 Days
Figure 5.18: Splitting tensile strength for silica fume mixes.
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Tensile strength
Figure 5.19: Splitting tensile strength for slag mixes.
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Tensile strength
Figure 5.20:
Splitting tensile strength
for combine slag & silica
fume mixes.
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Sorptivity test
ASTM C 1585; Sorptivity Test
recently
Require a concrete disc of at least 300gm weight
Concrete specimens are oven dried
One surface of the specimen is exposed to water and the change in
weight with time is measured (at least 5 measurements) over 30
minutes period
Plot the graph between penetration depth (i) and square root of
time (time1/2) to calculate Sorptivity
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Sorptivity test
Concrete
Specimen
Container
Water
Circular support
Surface sealant (electrical vinyl tape)
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Sorptivity test
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Sorptivity test
tSAi
Penetration depth (mm)
Constant
Rate of Absorption i.e. Sorptivity (mm/min1/2)
Exposure time (min)
One dimensional flow through partially saturated concrete can be
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Sorptivity test
i
Time1/2
Slope = Sorptivity (S) mm/min1/ 2
Constant = A
A
Wi
Cross sectional area (mm2)
Water density (gm/mm3)
Change in specimen weight (gm)
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Sorptivity test
Specimen Location and Code = C1-1 Specimen Diameter (mm) = 100 mm
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Sorptivity test
Table 5.1.1: Average Sorptivity test value at 28 and 56 days of age