Portland cement is the most important ingredient of concrete and is a versatile and relatively high cost material. Large scale production of cement is causing environmental problems on one hand and depletion of natural resources on other hand. This threat to ecology has led to researchers to use industrial by products as supplementary cementations material in making concrete. In this study, an attempt has been made to investigate the strength parameters of concrete made with partial replacement of cement by silica fume.
Portland cement is the most important ingredient of concrete and is a versatile and relatively high cost material. Large scale production of cement is causing environmental problems on one hand and depletion of natural resources on other hand. This threat to ecology has led to researchers to use industrial by products as supplementary cementations material in making concrete. In this study, an attempt has been made to investigate the strength parameters of concrete made with partial replacement of cement by silica fume.
Effects of Silica Fume and Fly Ash as Partial Replacement of Cement on Water ...idescitation
ndustrial byproducts such as Silica Fume (SF) and Fly Ash (FA) can be utilized
to enhance the strength and water permeability characteristics of High Performance
Concrete (HPC). The utilization of these industrial by products is becoming popular
throughout the world because of the minimization of their potential hazardous effects on
environment. This paper investigates the individual effects of Silica Fume and Fly Ash as a
partial replacement of Ordinary Portland Cement (OPC) on water permeability,
compressive strength, split tensile strength and flexural tensile strength of High
Performance Concrete (HPC). To investigate these properties of concrete, the total
investigation was categorized into two basic test groups - SF Group for Silica Fume and FA
Group for Fly Ash. Seven types of mix proportions were used to cast the test specimens for
both groups. The replacement levels of OPC by Silica Fume were 0%, 2.5%, 5%, 7.5%,
10%, 15% and 20% where replacement levels of OPC by Fly Ash were 0%, 5%, 10%, 15%,
20%, 25% and 30%. 1% super-plasticizer was used in all the test specimens for high
performance (i.e., high workability at lower water-binder ratio) and to identify the sharp
effects of Silica Fume and Fly Ash on the properties of concrete. Water-binder ratio was
kept 0.42 for all cases and the specimens were tested at ages of 7, 14 and 28 days.10% Silica
Fume and 20% Fly Ash showed the lowest water penetration depth of 11mm and 15 mm
respectively. 7.5% Silica Fume and 10% Fly Ash were found to be optimum for maximum
compressive strength, maximum split tensile strength as well as maximum flexural tensile
strength.
Silica fume-Definition,its production process,Its influence on various concrete such as fresh and hardened concrete , its mixing and curing process and also its available forms and real time examples of silica fume in projects in India and its benefits regarding productivity of economical and faster construction.
Effect of silica fume on the strength of cement mortareSAT Journals
Abstract
The replacement of sand/cement by certain percentage of silica fumes, resulted in the improvement in compressive strength of the mortar. Silica fumes to the highly pozzolanic materials because it consists essentially of silica in non- crystalline form with a high specific surface. It is used to improve the mechanical properties of the concrete. The main objective of this paper is to study the effect of silica fume on the compressive strength of mortar. Three proportions of mixes viz mix 1:3, mix 1:4 and mix 1:6 with different percentages of silica fumes replacement with sand/cement were used. The maximum increase in strength at the age of 28 days when sand is replaced by 15% of silica fume has been observed as 40% and in case of cement replaced with 15% of silica fume, the observed increase in compressive strength of mortar comes out to be 28%.
A quantitative cost analysis shows that with the replacement of cement and sand by silica fume, the in cost is more when sand is replaced and it is less when cement is replaced.
Keywords: pozzolanic, silica fumes, non- crystalline, compressive strength
Concrete is the most widely used construction material in India with annual consumption exceeding 100 million cubic meters.
High performance concrete is a concrete in which certain characteristics are developed for a particular application and environment, so that it will give excellent performance in the structure in which it will be placed.
A high-strength concrete is always a high performance concrete, but a high-performance concrete is not always a high-strength concrete.
Cellular Light Weight Concrete Blocks Machine- Manufacturers & Suppliers
Our proficient and dedicated professionals make the utmost use of these facilities and work round the clock with a client centric approach to meet the industrial requirements. These professionals are well versed and have updated knowledge on the latest technology which ensures hassle free and efficient procurement and storage. We have been highly benefited by our facilities, this being one of the reasons for establishing ourselves as a prominent organization.
www.clcblockmachine.in, www.clcplant.com
Microsilica is a byproduct from silicon metal or ferrosilicon industries, where these metals are produced in submerged electric arc furnaces. As the molten metal is produced, a silica-based gas is emitted. This gaseous fume, as it rises, cools rapidly and forms extremely minute, amorphous, spherical particles. The microsilica fume is collected in a bag house, a system for filtering the hot air and gases vented from the furnace.
Microsilica in concrete:
When it is used in concrete, it acts as a filler and as a cementitious material. The small
micro silica particles fill spaces between cement particles and between the cement
past matrix and aggregate particles. Microsilica fume also combines with calcium
hydroxide to form additional calcium hydrate through the pozzolanic reaction. Both of
these actions result in a denser, stronger and less permeable material.
Microsilica has been used as an addition to concrete up to 15 percent by weight of cement, although the normal proportion is 7 to 10 percent. With an addition of 15 percent, the potential exists for very strong, brittle concrete. It increases the water demand in a concrete mix; however, dosage rates of less than 5 percent will not typically require a water reducer. High replacement rates will require the use of a high
range water reducer.
How do micro silica work in concrete?
Microsilica improves concrete through two primary mechanisms — the basic pozzolanic reaction, and microfiller effect.
When water is added to portland cement hydration occurs forming two products, as shown below:
Cement +Water----------->Calcium Silicate Hydrate +Calcium Hydroxide
An Experimental Investigation on Strength Characteristics of Concrete with Pa...ijsrd.com
One of the approaches in improving the durability of concrete is to use blended cement materials such as fly ash, silica fume, slag and more recently, metakaolin. By changing the chemistry and microstructure of concrete, pozzolans reduce the capillary porosity of the cementitious system and make them less permeable to exterior chemical sources as well as reducing the internal chemical incompatilities such as alkali-silica reaction. The concrete industry is known to leave an enormous environmental footprint on Planet Earth. First, there are the sheer volumes of material needed to produce the billions of tons of concrete worldwide each year. Then there are the CO2 emissions caused during the production of Portland cement. Together with the energy requirements, water consumption and generation of construction and demolition waste, these factors contribute to the general appearance that concrete is not particularly environmentally friendly or compatible with the demands of sustainable development. Thus, use of these supplementary cementitious materials can reduce the effects of cement causing severe environmental impact. This study presents the results of different mechanical properties of concrete such as compressive strength, split tensile strength and flexural concrete by partially replacing cement with metakaolin and silica fume. The replacement of metakaolin is varied from 10%, 15%, 20% and 25% and silica fume from 6%, 8% and 10%. The property of concrete in fresh state that is the workability is also studied during the present investigation. The optimum doses of silica fume and metakaolin in combination were found to be 6% and 15% (by weight) respectively, when used as part replacement of ordinary Portland cement.
Effects of Silica Fume and Fly Ash as Partial Replacement of Cement on Water ...idescitation
ndustrial byproducts such as Silica Fume (SF) and Fly Ash (FA) can be utilized
to enhance the strength and water permeability characteristics of High Performance
Concrete (HPC). The utilization of these industrial by products is becoming popular
throughout the world because of the minimization of their potential hazardous effects on
environment. This paper investigates the individual effects of Silica Fume and Fly Ash as a
partial replacement of Ordinary Portland Cement (OPC) on water permeability,
compressive strength, split tensile strength and flexural tensile strength of High
Performance Concrete (HPC). To investigate these properties of concrete, the total
investigation was categorized into two basic test groups - SF Group for Silica Fume and FA
Group for Fly Ash. Seven types of mix proportions were used to cast the test specimens for
both groups. The replacement levels of OPC by Silica Fume were 0%, 2.5%, 5%, 7.5%,
10%, 15% and 20% where replacement levels of OPC by Fly Ash were 0%, 5%, 10%, 15%,
20%, 25% and 30%. 1% super-plasticizer was used in all the test specimens for high
performance (i.e., high workability at lower water-binder ratio) and to identify the sharp
effects of Silica Fume and Fly Ash on the properties of concrete. Water-binder ratio was
kept 0.42 for all cases and the specimens were tested at ages of 7, 14 and 28 days.10% Silica
Fume and 20% Fly Ash showed the lowest water penetration depth of 11mm and 15 mm
respectively. 7.5% Silica Fume and 10% Fly Ash were found to be optimum for maximum
compressive strength, maximum split tensile strength as well as maximum flexural tensile
strength.
Silica fume-Definition,its production process,Its influence on various concrete such as fresh and hardened concrete , its mixing and curing process and also its available forms and real time examples of silica fume in projects in India and its benefits regarding productivity of economical and faster construction.
Effect of silica fume on the strength of cement mortareSAT Journals
Abstract
The replacement of sand/cement by certain percentage of silica fumes, resulted in the improvement in compressive strength of the mortar. Silica fumes to the highly pozzolanic materials because it consists essentially of silica in non- crystalline form with a high specific surface. It is used to improve the mechanical properties of the concrete. The main objective of this paper is to study the effect of silica fume on the compressive strength of mortar. Three proportions of mixes viz mix 1:3, mix 1:4 and mix 1:6 with different percentages of silica fumes replacement with sand/cement were used. The maximum increase in strength at the age of 28 days when sand is replaced by 15% of silica fume has been observed as 40% and in case of cement replaced with 15% of silica fume, the observed increase in compressive strength of mortar comes out to be 28%.
A quantitative cost analysis shows that with the replacement of cement and sand by silica fume, the in cost is more when sand is replaced and it is less when cement is replaced.
Keywords: pozzolanic, silica fumes, non- crystalline, compressive strength
Concrete is the most widely used construction material in India with annual consumption exceeding 100 million cubic meters.
High performance concrete is a concrete in which certain characteristics are developed for a particular application and environment, so that it will give excellent performance in the structure in which it will be placed.
A high-strength concrete is always a high performance concrete, but a high-performance concrete is not always a high-strength concrete.
Cellular Light Weight Concrete Blocks Machine- Manufacturers & Suppliers
Our proficient and dedicated professionals make the utmost use of these facilities and work round the clock with a client centric approach to meet the industrial requirements. These professionals are well versed and have updated knowledge on the latest technology which ensures hassle free and efficient procurement and storage. We have been highly benefited by our facilities, this being one of the reasons for establishing ourselves as a prominent organization.
www.clcblockmachine.in, www.clcplant.com
Microsilica is a byproduct from silicon metal or ferrosilicon industries, where these metals are produced in submerged electric arc furnaces. As the molten metal is produced, a silica-based gas is emitted. This gaseous fume, as it rises, cools rapidly and forms extremely minute, amorphous, spherical particles. The microsilica fume is collected in a bag house, a system for filtering the hot air and gases vented from the furnace.
Microsilica in concrete:
When it is used in concrete, it acts as a filler and as a cementitious material. The small
micro silica particles fill spaces between cement particles and between the cement
past matrix and aggregate particles. Microsilica fume also combines with calcium
hydroxide to form additional calcium hydrate through the pozzolanic reaction. Both of
these actions result in a denser, stronger and less permeable material.
Microsilica has been used as an addition to concrete up to 15 percent by weight of cement, although the normal proportion is 7 to 10 percent. With an addition of 15 percent, the potential exists for very strong, brittle concrete. It increases the water demand in a concrete mix; however, dosage rates of less than 5 percent will not typically require a water reducer. High replacement rates will require the use of a high
range water reducer.
How do micro silica work in concrete?
Microsilica improves concrete through two primary mechanisms — the basic pozzolanic reaction, and microfiller effect.
When water is added to portland cement hydration occurs forming two products, as shown below:
Cement +Water----------->Calcium Silicate Hydrate +Calcium Hydroxide
An Experimental Investigation on Strength Characteristics of Concrete with Pa...ijsrd.com
One of the approaches in improving the durability of concrete is to use blended cement materials such as fly ash, silica fume, slag and more recently, metakaolin. By changing the chemistry and microstructure of concrete, pozzolans reduce the capillary porosity of the cementitious system and make them less permeable to exterior chemical sources as well as reducing the internal chemical incompatilities such as alkali-silica reaction. The concrete industry is known to leave an enormous environmental footprint on Planet Earth. First, there are the sheer volumes of material needed to produce the billions of tons of concrete worldwide each year. Then there are the CO2 emissions caused during the production of Portland cement. Together with the energy requirements, water consumption and generation of construction and demolition waste, these factors contribute to the general appearance that concrete is not particularly environmentally friendly or compatible with the demands of sustainable development. Thus, use of these supplementary cementitious materials can reduce the effects of cement causing severe environmental impact. This study presents the results of different mechanical properties of concrete such as compressive strength, split tensile strength and flexural concrete by partially replacing cement with metakaolin and silica fume. The replacement of metakaolin is varied from 10%, 15%, 20% and 25% and silica fume from 6%, 8% and 10%. The property of concrete in fresh state that is the workability is also studied during the present investigation. The optimum doses of silica fume and metakaolin in combination were found to be 6% and 15% (by weight) respectively, when used as part replacement of ordinary Portland cement.
An Experimental Investigation on Strength Characteristics of Concrete with P...IJMER
One of the approaches in improving the durability of concrete is to use blended cement
materials such as fly ash, silica fume, slag and more recently, metakaolin.. This study presents the results
of different mechanical properties of concrete such as compressive strength, split tensile strength and
flexural concrete by partially replacing cement with metakaolin and silica fume. The replacement of
metakaolin is varied from 10%, 15%, 20% and 25% and silica fume from 6%, 8% and 10%. The property
of concrete in fresh state, that is the workability is also studied during the present investigation.The
optimum doses of silica fume and metakaolin in combination were found to be 6% and 15% (by weight)
respectively, when used as part replacement of ordinary Portland cement.
STUDY ON DURABILITY OF CONCRETE WHEN BLENDED WITH MICRO SILICA AND FLYASHIjripublishers Ijri
The environment in some concrete structures can become very acidic due to formation of sulphuric acid converted
from hydrogen sulphide by bacterial action. Significant deteriation of concrete in such harsh environments has
been reported world wide. Deteriotation of sewer system may result in serious problem such as the loss of ability to
transport sewerage, contamaniation of ground and ground water, excessive ground settelements.
The Mechanical Properties of Concrete Incorporating Silica Fume as Partial Re...HARISH B A
Concrete is the most important engineering
material and the addition of some other materials may change
the properties of concrete. With increase in trend towards the
wider use of concrete for prestressed concrete and high rise
buildings there is a growing demand of concrete with higher
compressive strength. Mineral additions which are also
known as mineral admixtures have been used with cements
for many years. Silica fume particles are 100 times smaller
than the average cement particle. Its handling and disposal is
a point of concern because of the environment concerns. Silica
fume is usually categorized as a supplementary cementitious
material. These materials exhibit pozzolanic properties,
cementitious properties and a combination of both properties.
Due to these properties, it can affect the concrete behavior in
many ways. In the present work, an attempt has been made to
use silica fume as a supplementary material for cement and to
evaluate the limit of replacement of cement for M20 grade
concrete. The main aim of this work is to study the
mechanical properties of M20 grade control concrete and
silica fume concrete with different percentages (5, 10, 15 and
20%) of silica fume as a partial replacement of cement.
Globally the idea of sustainability has now taken a centre stage. The environmental concern focuses on overexploitation of natural resources such as limestone, clay, etc and release of harmful gaseous substance into the global environment from the cement industries worldwide.
Concrete Construction: Batching of mixes; casting process, compaction and curing;
requirement of mix design and casting of test cubes – removing cubes from moulds and
curing for strength tests; bar-bending equipments and preparation of reinforcement for
R C C works
Size Anddosageof Micro Silica Fume Behaviour for Partial Replacement of Cemen...iosrjce
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of mechanical and civil engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mechanical and civil engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
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4. Micro silica is an amorphous type of silica
dust mostly collected in bag house filters as
by product of the silicon and Ferro-silicon
production.
Micro silica consists of spherical particles with
an average particle size of 150 nm and a
specific surface area of 20m3/g.
Micro silica contains trace amounts of heavy
metal oxides and organic deposits, which
originate from natural raw materials.
5. Micro silica is a mineral admixture composes of
very fine solid spheres of silicon dioxide(sio2).
Micro silica is a by- product of the silicon and
ferrosilicon.
When pozzolanic materials are incorporated to
concrete , silica present is these materials react
with Ca(OH)2 released during hydration of cement
and cement forms additional calcium silicate
hydrate (C-S-H), which improve durability and
mechanical Properties of concrete.
6. Preliminary Investigations
For Preliminary Investigations , micro silica
and cement was subjected to physical and
chemical analyses to determine whether they
are in compliance with standard used
The replacement levels of cement by silica
fume are selected as 5%, 10%, 15%, 20%
and 25% for standard size of cubes for the
M30 grade of concrete .
The specimens of standard cubes
(150x150x150), were casted with silica fume.
7. • Cement
Ordinary portland cement
• Aggregates
There are the inert filler in the concrete mixture
which constitute between 70%-75% by volume of
the whole mixture.
• Water
The water used for the study was free of acids,
organic matter, suspended solids , alkalis and
impurities which when present may have adverse
effect on the strength of concrete,
8. Handling the micro silica
A cement tanker that could haul 35 metric
tons of cement accommodates only 7 to 9
tons of dry micro silica and requires 20 to 50
% more time for discharging.
Some producers mix micro silica with water to
form slurry that can be transported easily
without leaving any harmful effect.
9. When no water reducing agent is used , the
addition of micro silica to a concrete mix for
more water to maintain a given slump.
Water content can be held the same by using
a water reducer or super plasticizer along with
the micro silica.
Water reducing agents appear to have a
greater effect on micro sillica concrete than on
normal concrete.
Thus water demand for given micro silica
concrete can be controlled to be either greater
or smaller than for reference concrete.
10. The gel that forms during the first minutes of
mixing micro silica concrete takes up water and
stiffens the mixture , necessitating adjustment of
the timing of charging and placing.
When cement content and micro silica dosages
are relatively high, the mixture is so cohesive that
there is virtually no segregation of aggregates and
little bleeding.
This may cause problems for floor or slabs cast in
hot, windy weather because there is no water film
at the surface to compensate for evaporation.
11. 12 cubes for control and cement replacement
levels of 5%, 10%, 15%, 20%,and 25% were
produced . For compressive strength ,
150x150x150 mm cube moulds were used to
cast the cubes and 3 specimens were tested
for each age in a particular mix(i.e. the cubes
were crushed at 3, 7,14 and 28 days
respectively.
All freshly cast specimens were left in the
mould for 24 hours before being demoulded
and then submerged in water for curing until
the time of testing.
12. Mix proportioning by weight was used and the
cement/dried total aggregates ratio was 1:2:4.
Micro silica were used to replace OPC at
dosage levels of 5%, 10%, 15%, 20%, and
25% by weight of the binder. The mix
proportions were calculated.
13.
14. Compressive strength test were carried out at
specified ages on the cubes. The consisted of
the application of uniaxial compressive load
on the cube until failure at which point the
load require for failure of each cube was
noted , prior to testing , the density of cube
was determined using standard procedures
for density determination.
15.
16.
17. How does silica contribute to strength and
durability of concrete
Pozzolonic effect:
When water is added to OPC, hydration occurs
forming two products-
OPC + H2O =CSH + Ca(OH)2
In the presence of mcro silica, the silicon dioxide
from the micro silica will react with the calcium
hydroxide to produce more aggregate binding CSH
as follows:-
Ca(OH)2 + Sio2 +H2O= CSH
18. Micro silica is an extremely fine material ,with an
average diameters 100x finer than cement. This
eliminates bleed and weak transition zone between
aggregate and paste found in normal concrete.
The micro filler effect will greatly reduced
permeability and improves the paste to aggregate
bond of silica fume concrete compared to
conventional concrete.
The silica reacts rapidly providing high early age
strength and durability. The efficiency of micro
silica is 3-5 times that of OPC.
21. Cement replacement up to 10% with silica fume leads
to increase in compressive strength. From 15% there is
a decrease in compressive strength for 3, 7, 14, and 28
days curing period.
It was observed that the compressive strength of M30
grade of concrete is increased from 16.15% to 20.22%.
The maximum replacement level of silica is 10% for
M30 grade of concrete.
The use of micro silica in high strength concrete leads
to economical and faster construction.
Due to use of micro silica in a OPC concrete the life of
that concrete is increased 4-5 times than the OPC
concrete.