7/30/2019 Sulphate Resistance
1/13
SULPHATE RESISTANCE OF TERNARY
BLENDED
FIBRE REINFORCED CONCRETEA DISSERTATION ON
PARTIAL FULFILLMENT OF MASTER OF TECHNOLOGY
BY
A.BHASKARRoll No.11016T6013,M.Tech IV Semester
Under The Guidence Of
Shri D.Hari Krishna Asso.Prof.CED, KITS, Warangal
DEPARTMENT OF CIVIL ENGINEERING
KAKATIYA INSTITUTE OF TECHNOLOGY AND SCIENCE, WARANGAL - 15.
7/30/2019 Sulphate Resistance
2/13
CONTENTS
OBJECTIVES
INTRODUCTION
FACTORS DEPENDS ON SEVERITY OF SULPHATE ATTACK
SCOPE
REFERENCES
7/30/2019 Sulphate Resistance
3/13
OBJECTIVES
To study the effect of sodium sulphate at 5% concentration on Ternary
blended fibre reinforced concrete at 90 days of immersion in sulphate
solution.
To find the optimum mix to resist the effect of Sulphates.
To study the effect of partial replacement of cement by silica and Fly ash in
different percentages at 28 days compressive strength.
7/30/2019 Sulphate Resistance
4/13
INTRODUCTION
Why Ternary blend
The particle packing is the main reason. The fly ash particle is often finer
than the cement. The silica fume particles can perform better in particle
packing since these are intermediate size.
7/30/2019 Sulphate Resistance
5/13
Effect of ternary cement system
Micro silica compensates for low early strength of concrete.
Fly ash increases long-term strength development of micro silica concre
Fly ash due to presence of spherical leads to improved workability and
reduction in water demand
7/30/2019 Sulphate Resistance
6/13
Source of Sulphate
Seawater and ground water are the main sources of external sulphate
Industrial effluents and wastes such as in industries associated
with the manufacture of chemicals, batteries, aluminium and in
the mining industry.
Internal Source
Portland cement might be over-sulfated.
presence of natural gypsum in the aggregate.
Admixtures also can contain small amounts of sulfates
External Source
7/30/2019 Sulphate Resistance
7/13
Mechanism of Sulphate Attack
Reaction of the sulfate with calcium hydroxide liberated during thehydration of the cement, forming calcium sulfate (gypsum)
Reaction of the calcium sulfate with the hydrated calcium aluminate,
forming calcium sulpho aluminate (ettringite).
Both of these reactions result in an increase in the volume of solids
which is the cause of expansion and disruption of concretes exposed
to sulfate solutions.
7/30/2019 Sulphate Resistance
8/13
Recommendations for normal concrete subject to
sulfate attack
Exposure
Water soluble
sulfate (SO4) in
soil, percent
Sulfate (SO4) in
water, ppm
Recommendati
ons
NEGLIGIBLE Under 0.1 Under150
MODERATE0.1 to 0.2 150 - 1500
PS cement
0.5 W/C Ratio
SEVERE 0.2 to 2.0 1500 10,000
PS cement
0.45 W/C Ratio
VERY SEVERE Over 2.0 Over 10,000
PS cement+Admix
>0.45 W/C
Ratio
7/30/2019 Sulphate Resistance
9/13
Severity of sulfate attack on concrete depends on
the following
Type of sulfate
Concentration of the sulfate
Whether the sulfate solution is stagnant or flowing
Pressure
Temperature
7/30/2019 Sulphate Resistance
10/13
Prevention measures of Sulphate attack
1. Cement type and content:
2. Admixtures : That effects reduction in water-cement ratio
and/or increased workability can enhance the sulfate resistance
of concrete, provided they are not used to reduce its cement
content
Cements with low C3A content are less vulnerable to sulfate
attack
Higher cement content significantly reduces the rate of sulfate
attack
7/30/2019 Sulphate Resistance
11/13
SCOPE OF PRESENT INVESTIGATION
The present experiment is carried out to investigate the strength of
ternary blended steel fiber reinforced concrete on M30 grade
concrete with 6% and 15% replacement of cement by silica fume
and fly ash respectively and 0%, 0.5%, 0.75%, 1.0% and 1.25%
addition of steel fibers
7/30/2019 Sulphate Resistance
12/13
Mehta, P K Concrete Structures, Properties and Materials Prentice Hall,
Inc, Englewood Cliffs, New Jersey,
M S Shetty,Concrete Technology, Published May 1st 1987 by Chand (S.) &
Co Ltd, 632 pages, Hardcover.
M L Gambhir, Concrete Technology, Published by Tata McGraw-Hill
Education, 01-Jul-2004
Adam M Neville, Properties ofConcreteBookby John Wiley & Sons
Publisher
References
CEMENT CONCRETE & AGGREGATES Australia JULY 2OO2 journal
7/30/2019 Sulphate Resistance
13/13
THANKYOU