Construction Materials from Agricultural &Industrial Waste

A study of alternative materials for cement and fine aggregate

Submitted by Ananthu Raju

Guide Ar.Sini

B. Arch Dissertation March 2018

C.A.T C O L L E G E O F A R C H I T E C T U R E T R I VA N D R U M M u l a y a r a P. O , T h i r u v a n a n t h a p u r a m This thesis is the property of the institution and the author. it should not be re-produced without prior permission

2 A study of alternative materials for cement and fine aggregate

CHAPTER 1: INTRODUCTION In the world of construction, buildings are able to make a major contribution to a more sustainable future for our planet. The OECD estimates that buildings in developed countries account for more than 40% of energy consumption over their lifetime (incorporating raw material production, construction, operation, maintenance and decommissioning). Add to this the fact that for the first time in human history over half of the world’s population now lives in urban environments and it’s clear that sustainable buildings have become vital for securing long-term environmental, economic and social viability.

Since the 1992 Earth Summit in Rio, when Agenda 21 was formulated as an international blueprint for sustainable development, all sectors of society have been in the process of interpreting and pursuing sustainability and sustainable development within their specific context. To address the role of human

settlements

in

sustainable

development,

a

second

international action plan, the Habitat Agenda, was prepared. The Agenda document provided a detailed overview of the concepts, issues and challenges of sustainable development and sustainable construction, and posed certain challenges to the construction industry.

However, creating a sustainable built environment in the developing world requires a different approach to that taken by the developed world and this is not often clearly understood and discussed. a special Agenda 21 for Sustainable Construction in Developing Countries was commissioned as part of the Action Plan for the implementation of the CIB Agenda 21 on Sustainable Construction

A study of alternative materials for cement and fine aggregate 3

and to further the CIB’s pro-active approach on sustainable construction. Although the process is driven by the CIB, it is not a CIB exclusive project but a participative process involving many other networks on sustainable human settlement development and developing countries, and is supported by UNEP-IETC. Sustainable construction can make a huge difference to global environmental sustainability, particularly through a drastic reduction in the use of natural resource consumption and energy intensive materials like cement, steel, aggregates and aluminium. Availability of conventional construction materials will fall considerably short of their demand despite improved productivity, and it is necessary to develop alternatives for them.

Current global MSW generation levels are approximately 1.3 billion tonnes per year, and are expected to increase to approximately 2.2 billion tonnes per year by 2025. This represents a significant increase in per capita waste generation rates, from 1.2 to 1.42 kg per person per day in the next fifteen years. And these wastes are not having any industrial applications, so it can be innovatively using these wastes as a raw material in the civil engineering field. By using these wastes as the non-conventional and reuse or recycling of waste material in order to compensate the lack of the natural resources. So, wastes can be used to produce new products or can be used as admixtures in the civil engineering field.

So the environment is protected from waste deposits.

4 A study of alternative materials for cement and fine aggregate

1. INTRODUCTION AIM To study alternatives for cement and fine aggregate in building construction OBJECTIVES  To show harmful effects of cement and aggregates currently used in building construction industry  To develop a sustainable way of construction by using alternative construction materials METHODOLOGY

A study of alternative materials for cement and fine aggregate 5

SCOPE  To meet the ever-increasing demand for the energy efficient building construction materials that can minimalise the emission of CO2 into the atmosphere

LIMITATIONS  Unavailability of live data about new technology in building construction 

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CHAPTER 3: Data Collection

A study of alternative materials for cement and fine aggregate 7

1.CEMENT

https://www.google.co.in/search?q=cement&client

A cement is a binder, a substance used for construction that sets, hardens and adheres to other materials, binding them together.

Cement is seldom used on its own, but rather to bind sand and gravel (aggregate) together. Cement is used with fine aggregate to produce mortar for masonry, or with sand and gravel aggregates to produce concrete.

Non-hydraulic cement will not set in wet conditions or under water; rather, it sets as it dries and reacts with carbon dioxide in the air. It is resistant to attack by chemicals after setting.

Hydraulic

cements (e.g., Portland

become adhesive due ingredients

and

to

water.

a chemical The

cement)

set

reaction between

chemical

reaction

and the

results

dry in

mineral hydrates that are not very water-soluble and so are quite durable in water and safe from chemical attack. This allows setting in wet conditions or under water and further protects the hardened material from chemical attack. The chemical process for hydraulic cement found by ancient Romans used volcanic ash (pozzolana) with added lime (calcium oxide).

8 A study of alternative materials for cement and fine aggregate

1.1 MANUFACTURE OF CEMENT

https://www.google.co.in/search?client=opera&hs=B6j&biw=1496&bih=764&tbm=isch&sa

Portland cement is manufactured by crushing, milling and proportioning the following materials: o Lime or calcium oxide, CaO: from limestone, chalk, shells, shale or calcareous rock o Silica, SiO2: from sand, old bottles, clay or argillaceous rock o Alumina, Al2O3: from bauxite, recycled aluminum, clay o Iron, Fe2O3: from from clay, iron ore, scrap iron and fly ash o Gypsum, CaSO4.2H20: found together with limestone The materials, without the gypsum, are proportioned to produce a mixture with the desired chemical composition and then ground and blended by one of two processes - dry process or wet process. The materials are then fed through a kiln at 2,600ยบ F to produce grayishblack pellets known as clinker. The alumina and iron act as fluxing agents which lower the melting point of silica from 3,000 to 2600ยบ F.

A study of alternative materials for cement and fine aggregate 9

After this stage, the clinker is cooled, pulverized and gypsum added to regulate setting time. It is then ground extremely fine to produce cement.

Because of the complex chemical nature of cement, a shorthand form is used to denote the chemical compounds. The shorthand for the basic compounds is:

1.1.1 CHEMICAL COMPOSITION OF CLINKER The cement clinker formed has the following typical composition:

Representative weights only. Actual weight varies with type of cement.

Source: Mindess & Young

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1.1.2 PROPERTIES OF CEMENT COMPOUNDS These compounds contribute to the properties of cement in different ways; Tricalcium aluminate, C3A: It liberates a lot of heat during the early stages of hydration, but has little strength contribution. Gypsum slows down the hydration rate of C3A. Cement low in C3A is sulphate resistant.

Tricalcium silicate, C3S: This compound hydrates and hardens rapidly. It is largely responsible for Portland cement’s initial set and early strength gain.

Dicalcium silicate, C2S: C2S hydrates and hardens slowly. It is largely responsible for strength gain after one week.

Ferrite, C4AF: This is a fluxing agent which reduces the melting temperature of the raw materials in the kiln (from 3,000o F to 2,600o F). It hydrates rapidly but does not contribute much to strength of the cement paste.

By mixing these compounds appropriately, manufacturers can produce different types of cement to suit several construction environments.

A study of alternative materials for cement and fine aggregate 11

1.3 Life Cycle Assessment (LCA) LCA is used to evaluate the impact of processes or products on the environment. The inclusion of every stage of the process or product's life cycle is fundamental to this analysis. In the case of products, every stage from the production of the raw materials to the end of their useful lives and their use and maintenance should be included.

Thus, all significant environment impacts in their life cycle can be addressed . For cement, a cradle to grave assessment is especially difficult because cement has so many end uses, and each use has a unique, often complex life-cycle. Therefore inventory analyses and complete LCAs can be quite complicated.

1.3 HARM EFFECTS OF CEMENT

https://www.google.co.in/search?q=HARMFUL+EFFECTS+OF+CEMENT&client

The production of cement involves the consumption of large quantities of raw materials, energy, and heat. Cement production also results in the release of a significant amount of solid waste materials and gaseous emissions. The manufacturing process is very complex, involving a large number of materials (with varying material

12 A study of alternative materials for cement and fine aggregate

properties), pyro processing techniques (e.g., wet and dry kiln, preheating, recirculation), and fuel sources (e.g., coal, fuel oil, natural gas, tires, hazardous wastes, petroleum coke).

ENVIRONMENTAL IMPACTS The main environmental issues associated with cement production are consumption of raw materials and energy use as well as emissions to air. Waste water discharge is usually limited to surface run off and cooling water only and causes no substantial contribution to water pollution. The storage and handling of fuels is a potential source of contamination of soil and groundwater. Additionally, the environment can be affected by noise and odors.

The key polluting substances emitted to air are dust, carbon oxides, nitrogen oxides (NOx) and sulphur dioxide (SO2). Carbon oxides, polychlorinated dibenzo-p-dioxins and dibenzofurans, total organic carbon, metals, hydrogen chloride and hydrogen fluoride are emitted as well. The type and quantity of air pollution depend on different parameters, e.g. inputs (the raw materials and fuels used) and the type of process applied.

1.3.1 EMISSIONS TO AIR Emissions to air arise during the manufacture of cement.In this section, ranges of air pollutant emissions are presented for the process of cement production, including other process steps, such as the storage and handling of, e.g. raw materials, additives and fuels

A study of alternative materials for cement and fine aggregate 13

including waste fuels. Relevant to cement manufacture including the use of waste are:  Oxides of nitrogen (NOx) and other nitrogen compounds  Sulphur dioxide (SO2) and other sulphur compounds dust,  Total organic compounds (TOC) including volatile organic compounds (VOC),

polychlorinated dibenzo-p-dioxins and

dibenzofurans (PCDDs and PCDFs),

metals and their

compounds,  Hydrogen fluoride (HF),  Hydrogen chloride (HCl),  Carbon monoxide (CO).

Not mentioned on the list, but considered to be relevant for cement production is carbon dioxide (CO2). Furthermore, emissions of NH 3 may be considered to be relevant, especially when using secondary measures/techniques for NOx reduction. The main emissions from the production of cement are emissions to air from the kiln system. The main constituents of the exit gases from a cement kiln are nitrogen from the combustion air; CO 2 from calcination of CaCO3 and combustion of fuel;water vapour from the combustion process and from the raw materials; and excess oxygen.

The cement manufacturing industry is under close scrutiny these days because of the large volumes of CO2 emitted. Concern over the impact of anthropogenic carbon emissions on the global climate has increased in recent years due to growth in global warming awareness. In addition to the generation of CO 2 the cement manufacturing process produces millions of tons of the waste product cement kiln dust each year contributing to respiratory and pollution health risks . The cement industry has made significant progress in reducing CO2 emissions through improvements in process and

14 A study of alternative materials for cement and fine aggregate

efficiency, but further improvements are limited because CO 2 production is inherent to the basic process of calcinating limestone.

1.3.2 CONSUMPTION OF RAW MATERIAL Cement manufacture is a high volume process. Typical averages in below Table indicate consumptions of raw materials for the production of cement in the European Union. The figures in the final column are for a plant with a clinker production of 3000 tones/day or 1 million tones/year, corresponding to 1,23 million tones cement per year based on the average clinker content in European cement Consumption of raw materials in cement production in tones [4]

The use of wastes as raw materials in the clinker burning process can replace a relatively large amount of raw materials. The quantities of wastes used as raw materials in clinker production have more than doubled since 2001. In 2004, waste raw materials used in clinker production allowed the cement industry to make a direct saving of almost 14 million tonnes of conventional raw materials, which is equivalent to about 6,5 % of the natural raw materials needed.

However, these waste raw materials have to show and meet characteristics, chemical element sand components which are necessary for the clinker burning process. These waste materials may have an impact on the emissions behaviour of the process and an effect on the emissions.

A study of alternative materials for cement and fine aggregate 15

In Table 4 there are listed the consumption of wastes used as raw materials characterized by chemical elements used by the EU-27 in 2003 and 2004 for clinker production.

1.3.3 CONSUMPTION OF ENERGY The cement production needs the very high amount of energy. Energy cost represents 40% of total production costs involved in producing of 1 tone of cement. Thermal energy demand (fuel) and electrical energy demand are the most important. Specific energy consumption depends on size and plant design, raw materials properties and its moisture, specific caloric values of fuel, throughput of kiln, type of clinker and many other factors. Thermal energy demand is in range of 3000 - 6500 MJ per 1 tone of clinker, the electricity demand ranges from 90 to 150 kWh per 1 tone of cement.

1.3.4 CONSUMPTION OF WATER Water is used at a number of stages during the production process. In only some cases, water is used for the preparation of raw material, in clinker burning and cooling processes, such as the cooling of gases, as well as in the technological process for slurry production. In the semi-dry process, water is used for pelletising the dry raw meal.

Plants using the wet process use more water (per tonne of cement produced) in preparing the kiln feed slurry and a typical water consumption of 100 – 600 litres water per tonne clinker is reported.

Furthermore, for special applications, water is used for clinker cooling and a water usage of around 5 m3/hour has been reported. In most cases, the water consumed is not potable water.

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1.4 CEMENT SUBSTITUTES 1.4.1 PULVERISED FUEL ASH (PFA) Fly ash into two categories based on calcium content; (i)

Fly ash resulting from combustion of anthracite and bituminous coal with CaO less than 5%

(ii)

(ii) Fly ash resulting from combustion of lignite and subbituminous coal with CaO up to 15-35%

Two types of fly ash; (i)

Class C

(ii)

Class F

The distinction between Class F and Class C fly ash is based on the sum of the total silicon, aluminum, and iron (Si02+Al203+Fe2C>3) in the ash. When the sum is greater than 70% an ash is classified as Class F. When the sum lies in the range of 50% to 70% the ash is classified as Class C. Determination of chemical composition of fly ash is mandatory for classification of fly ash as per existing standards. In general, the chemical composition of fly ash is typically made up of silicon, calcium, aluminum, iron, magnesium, and sulphur oxides along with carbon and various trace elements. These elements are found in the ash because of their high melting points and the short duration of the ash particles actually remain in the furnace during combustion. The mineral quartz (SiC>2) survives the combustion process and remains

A study of alternative materials for cement and fine aggregate 17

as quartz in the coal ash. Other minerals decompose, depending on the temperature, and form new minerals. The clay minerals lose water and may melt, forming alumino-silicate crystalline and noncrystalline (glassy) materials. Elements such as Fe, Ca, and Mg combine with oxygen in the air to form oxide minerals, such as magnetite (Fe 3O4), lime (CaO) and magnesia (MgO).  Physical Properties The fly ash particles are generally glassy, solid or hollow and spherical in shape. The hollow spherical particles are called as cenospheres. The fineness of individual fly ash particle rage from 1 micron to 1 mm size. The fineness of fly ash particles has a significant influence on its performance in cement concrete. The fineness of particles is measured by measuring specific surface area of fly ash by Blaine's specific area technique. Greater the surface area more will be the fineness of fly ash. The other method used for measuring fineness of fly ash is dry and wet sieving. The specific gravity of fly ash varies over a wide range of 1.9 to 2.55.  Pozzolanic Property Pozzolanic activity of fly ash is an indication of the lime fly ash reaction. It is mostly related to the reaction between reactive silica of the fly ash and calcium hydroxide which produce calcium silicate hydrate (C-S-H) gel which has binding properties. The alumina in the pozzolana may also react in the fly ash lime or fly ash cement system and produce calcium aluminate hydrate, ettringite, gehlenite and calcium monosulpho-aluminate hydrate. Thus the sum of reactive

18 A study of alternative materials for cement and fine aggregate

silica and alumina in the fly ash indicate the pozzolanic activity of the fly ash.  Chemical Requirement (according to BIS); -

 Physical Requirements; -

A study of alternative materials for cement and fine aggregate 19

There are three basic approaches for selecting the quantity of fly ash in cement concrete (i)

Partial Replacement of Ordinary Portland Cement (OPC)-the simple replacement method

(ii)

Addition of fly ash as fine aggregates - the addition method

20 A study of alternative materials for cement and fine aggregate

(iii)

Partial replacement of OPC, fine aggregate, and water- a modified replacement method

https://www.ntpc.co.in/ash-download/1674/0/fly-ash-cement-concrete-–-resource-high-strength-and-durabilitystructure-lower-cost

 Simple Replacement Method In this method a part of the OPC is replaced by fly ash on a one to one basis by mass of cement. In this process, the early strength of concrete is lower and higher strength is developed after 56-90 days.

At early ages fly ash exhibits very little cementing value. At later ages when liberated lime resulting from hydration of cement, reacts with fly ash and contributes considerable strength to the concrete. This method of fly ash use is adopted for mass concrete works where initial strength of concrete has less importance compared to the reduction of temperature rise.  Addition Method

A study of alternative materials for cement and fine aggregate 21

In this method, fly ash is added to the concrete without corresponding reduction in the quantity of OPC. This increases the effective cementitious content of the concrete and exhibits increased strength at all ages of the concrete mass. This method is useful when there is a minimum cement content criteria due to some design consideration.  Modified replacement method This method is useful to make strength of fly ash concrete equivalent to the strength of control mix (without fly ash concrete) at early ages i.e. between 3 and 28 days. In this method fly ash is used by replacing part of OPC by mass along with adjustment in quantity of fine aggregates and water. The concrete mixes designed by this method will have a total weight of OPC and fly ash higher than the weight of the cement used in comparable to control mix i.e. without fly ash mix. In this method the quantity of cementitious material (OPC + Fly ash) is kept higher than quantity of cement in control mix (without fly ash) to offset the reduction in early strength.

Examples of use of fly ash in concrete; -

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Prudential Building

Petronas towers

https://www.google.co.in/search? client=opera&hs=Prudential+Building+in+chicago&oq=Prudential+Building+in+chicago&gs

 Fly ash concrete was used in Prudential Building,The first tallest building in Chicago after World war II 

About 60,000 cum of fly ash concrete with an estimated saving of 3,000 tonne of Ordinary Portland Cement was used in Lednock Dam construction in UK during the year 1955.

 About 60,000 m of fly ash concrete with 80/20 Ordinary Portland Cement/ fly ash having average slump of 175 mm was used in the piles and the foundation slab to meet the

A study of alternative materials for cement and fine aggregate 23

requirement of sulphate resistance concrete of Ferrybridge C power station in UK during 1964.  Fly ash has been used in construction of world's tallest building “Petronas towers of Kuala Lampur. The concrete used in the building was of two grades 80 MPa and 60 MPa. The fly ash content was about 37.5 % of total cementitious content in mix.

Construction completed in the year 1998.



Fly ash from NTPC's Dadri Thermal power stations is being utilized in prestigious Delhi Metro Rail Corporation (DMRC) works at New Delhi. More than 60,000 tonne of fly ash has been utilized in the work so far. In this project, the requirement of cement concrete was high strength, high durability (less shrinkage and & thermal crakes), low heat of hydration, easy placement, cohesiveness and good surface finish. Use of fly ash in concrete has fulfilled the entire above requirements .

1.4.2 GROUND GRANULATED BLAST-FURNACE SLAG (GGBS) Ground Granulated Blast furnace Slag (GGBS) is a by product from the blast furnaces used to make iron. These operate at a temperature of about 1500 degrees centigrade and are fed with a carefully controlled mixture of iron ore, coke and limestone. The iron ore is reduced to iron and the remaining materials from a slag that floats on

24 A study of alternative materials for cement and fine aggregate

top of the iron. This slag is periodically tapped off as a molten liquid and if it is to be used for the manufacture of GGBS it has to be rapidly quenched in large volumes of water. The quenching optimises the cementitious properties and produces granules similar to coarse sand. This granulated slag is then dried and ground to a fine powder.

The chemical composition of a slag varies considerably depending on the composition of the raw materials in the iron production process.

Silicate and aluminate impurities from the ore and coke are combined in the blast furnace with a flux which lowers the viscosity of the slag.

In the case of pig iron production the flux consists mostly of a mixture of limestone and forsterite or in some cases dolomite. In the blast furnace the slag floats on top of the iron and is decanted for separation.

Typical chemical composition:

Typical physical properties:-

 Calcium oxide = 40%

 Colour : off white

 Silica = 35%

 Specific gravity : 2.9

 Alumina = 13%

 Bulk density : 1200 Kg/m3

A study of alternative materials for cement and fine aggregate 25

https://www.slideshare.net/avinashshaw18/ggbs-40989217

 Applications & Uses Of GGBS GGBS is used to make durable concrete structures in combination with ordinary Portland cement and/or other pozzolanic materials.

GGBS has been widely used in Europe, and increasingly in the United States and in Asia (particularly in Japan and Singapore) for its superiority in concrete durability, extending the lifespan of buildings from fifty years to a hundred years.

Two major uses of GGBS are in the production of quality-improved slag cement, namely Portland Blast furnace cement (PBFC) and highslag blast-furnace cement (HSBFC), with GGBS content ranging typically from 30 to 70% and in the production of ready-mixed or sitebatched durable concrete. Concrete made with GGBS cement sets more slowly than concrete made with ordinary Portland cement, depending on the amount of GGBS in the cementitious material, but also continues to gain strength over a longer period in production conditions. This results in lower heat of hydration and lower

26 A study of alternative materials for cement and fine aggregate

temperature rises, and makes avoiding cold joints easier, but may also affect construction schedules where quick setting is required.

GGBS Concrete  GGBS Proportions On its own, ground granulated blast furnace slag (GGBS) hardens very slowly and, for use in concrete, it needs to be activated by combining it with Portland cement. A typical combination is 50% GGBS with 50% Portland cement, but percentages of GGBS anywhere between 20 and 80 % are commonly used. The greater the percentage of GGBS, the greater will be the effect on concrete properties.  Setting Time The setting time of concrete is influenced by many factors, in particular temperature and water/cement ratio. With GGBS, the setting time will be extended slightly, perhaps by about 30 minutes.

The effect will be more pronounced at high levels of GGBS and/or low temperatures. An extended setting time is advantageous in that the concrete will remain workable longer and there will be less risk of cold joints. This is particularly useful in warm weather.  Water Demand The differences in rheological behaviour between GGBS and Portland cement may enable a small reduction in water content to achieve equivalent consistence class.

A study of alternative materials for cement and fine aggregate 27

http://iosrjournals.org/iosr-jmce/papers/vol12-issue4/Version-6/I012467682.pdf

 Sustainability Ground granulated blast furnace slag „GGBS‟ is one of the „greenest‟ of construction materials. Its only raw material is a very specific slag that is a by product from the blast furnaces manufacturing iron.

Manufacturing of „GGBS‟ utilises all of the slag and produces no significant waste. As well as the environmental benefit of utilising a by product, „GGBS‟ replaces something that is produce by a highly energy intensive process. By comparison with Portland cement, manufacture of GGBS requires less than a fifth the energy and produces less than a fifteenth of the carbon dioxide emissions.

Further „green‟ benefits are that manufacture of GGBS does not require the quarrying of virgin materials,

28 A study of alternative materials for cement and fine aggregate

1.4.3 Examples of other alternatives for concrete;  Silica Fume Silica fume is a by-product from the manufacture of silicon. It is an extremely fine powder (as fine as smoke) and therefore it is used in concrete production in either a densified or slurry form. Due to economic considerations, the use of silica fume is generally limited to

high

strength

concretes

or

concretes

in

aggressive

environmental conditions. The most commonly used proportion of silica fume in UK - produced combinations is 10% by mass of total cementitious

content.

 Limestone Fines Limestone fines can be used as a constituent of cement to produce Portland limestone cement. BS 7979 [12] provides additional information on the specification of limestone fines for use with Portland cement. The most commonly used proportions of limestone fines in UK-produced combinations is 6-10% by mass of total cementitious content.

A study of alternative materials for cement and fine aggregate 29

2. SAND Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz which because of its chemical inertness and considerable hardness, is the most common mineral resistant to weathering.

Sand is an ingredient in plaster and concrete and is added to clays to reduce shrinkage and cracking in the manufacture of bricks. Sand in the river channel and floodplains constitutes an important raw material in the construction industry and has a variety of uses in this sector. River sand is used along with cement, gravel, water and steel for making reinforced concrete. Along with cement and water, it is used as mortar for joint filling and plastering.

Excessive instream sand-and-gravel mining causes the degradation of rivers. Instream mining lowers the stream bottom, which may lead to bank erosion. Depletion of sand in the streambed and along coastal areas causes the deepening of rivers and estuaries, and the enlargement of river mouths and coastal inlets. It may also lead to saline-water intrusion from the nearby sea. The effect of mining is compounded by the effect of sea level rise. Any volume of sand exported from streambeds and coastal areas is a loss to the system.

Impacts of sand mining can be broadly clasified into three categories:  Physical The large-scale extraction of streambed materials, mining and dredging below the existing streambed, and the alteration of channelbed form and shape leads to several impacts such as erosion of channel bed and banks, increase in channel slope, and change in channel morphology. These impacts may cause: (1) the undercutting and collapse of river banks, (2) the loss of adjacent land and/or structures, (3) upstream erosion as a result of an increase in channel slope and changes in flow velocity, and (4) downstream erosion due to increased carrying capacity of the stream, downstream changes in patterns of deposition, and changes in channel bed and habitat type.

30 A study of alternative materials for cement and fine aggregate

 Water Quality Mining and dredging activities, poorly planned stockpiling and uncontrolled dumping of overburden, and chemical/fuel spills will cause reduced water quality for downstream users, increased cost for downstream water treatment plants and poisoning of aquatic life.  Ecological Mining which leads to the removal of channel substrate, resuspension of streambed sediment, clearance of vegetation, and stockpiling on the streambed, will have ecological impacts. These impacts may have an effect on the direct loss of stream reserve habitat, disturbances of species attached to streambed deposits, reduced light penetration, reduced primary production, and reduced feeding opportunities.

2.1 FINE AGGREGATE AND COARSE AGGREGATE The importance of using the right type and quality of aggregates cannot be overemphasized. The fine and coarse aggregates generally occupy 60% to 75% of the concrete volume (70% to 85% by mass) and strongly influence the concrete’s freshly mixed and hardened properties, mixture proportions, and economy.

Fine aggregates generally consist of natural sand or crushed stone with most particles smaller than 5 mm (0.2 in.).

Coarse aggregates consist of one or a combination of gravels or crushed stone with particles predominantly larger than 5 mm (0.2 in.) and generally between 9.5 mm and 37.5 mm (3⁄8 in. and 11⁄2 in.).

A study of alternative materials for cement and fine aggregate 31

Fine aggregate

Coarse aggregate http://www.sginstit

ute.in/Downloads/Civil_Downloads/LectureNo_4.pdf

Somenatural aggregate deposits, called pit-run gravel, consist of gravel and sand that can be readily used in concrete after minimal processing. Natural gravel and sand are usually dug or dredged from a pit, river, lake, or seabed.Crushed stone is produced by crushing quarry rock, boulders,cobbles, or large-size gravel.

2.1.1 CHARACTERISTICS OF AGGREGATES  Grading Grading is the particle-size distribution of an aggregate as determined by a sieve analysis (ASTM C 136 or AASHTO T 27). The aggregate particle size is determined by using wire-mesh sieves with square openings. The seven standard ASTM C 33 (AASHTO M 6/M 80) sieves for fine aggregate have openings ranging from 150 μm to 9.5 mm (No. 100 sieve to 3⁄8 in.). The 13 standard sieves for coarse aggregate have openings ranging from 1.18 mm to 100 mm (0.046 in. to 4 in.). Tolerances for the dimensions of openings in sieves are listed in ASTM E 11 (AASHTO M 92).

32 A study of alternative materials for cement and fine aggregate

The range of particle sizes in aggregate http://www.sginstitute.in/Downloads/Civil_Downloads/LectureNo_4.pdf

The grading and grading limits are usually expressed as the percentage of material passing each sieve. .

http://www.sginstitute.in/Downloads/Civil_Downloads/LectureNo_4.pdf

There are several reasons for specifying grading limits and nominal maximum aggregate size; they affect relative aggregate proportions as well as cement and water requirements, workability, pumpability, economy, porosity, shrinkage, and durability of concrete. Variations in grading can seriously affect the uniformity of concrete from batch to batch. Very fine sands are often uneconomical; very coarse sands and coarse aggregate can produce harsh, unworkable mixtures. In general, aggregates that do not have a large deficiency or excess of

A study of alternative materials for cement and fine aggregate 33

any size and give a smooth grading curve will produce the most satisfactory results.

GRADING OF FINE AGGREGATE; -

http://civil.emu.edu.tr/courses/civl284/4%20Aggregates.pdf

GRADING OF COARSE AGGREGATE; -

http://civil.emu.edu.tr/courses/civl284/4%20Aggregates.pdf

 Fineness Modulus (FM) The results of aggregate sieve analysis is expressed by a number called Fineness Modulus obtained by adding the sum of the cumulative percentages by mass of a sample aggregate retained on each of a specified series of sieves and dividing the sum by 100.

The following limits may be taken as guidance: 1. Fine sand : Fineness Modulus : 2.2 - 2.6 2. Medium sand: Fineness Modulus : 2.6 - 2.9 3. Coarse sand : Fineness Modulus : 2.9 - 3.2

34 A study of alternative materials for cement and fine aggregate

A sand having a fineness modulus more than 3.2 will be unsuitable for making satisfactory concrete.  Physical Properties of Aggregate: Specific Gravity Indian Standard Specification IS: 2386 (Part III) of 1963 gives various procedures to find out the specific gravity of different sizes of aggregates.

http://www.sginstitute.in/Downloads/Civil_Downloads/LectureNo_4.pdf

 Bulk Density The cylindrical measure is filled about 1/3 each time with thoroughly mixed aggregate and tamped with 25 strokes by a bullet ended tamping rod, 16 mm diameter and 60 cm long.

The net weight of the aggregate in the measure is determined and the bulk density is calculated in kg/litre.

http://www.sginstitute.in/Downloads/Civil_Downloads/LectureNo_4.pdf

A study of alternative materials for cement and fine aggregate 35

2.2 FINE AGGREGATE SUBSTITUTE 2.2.1 SUGARCANE BAGASSE ASH Sugarcane is one of the major crops grown in over 110 countries and its total production is over 1500 million tons.In India only, sugarcane production is over 300 million tons/year that cause about 10 million tons of sugarcane bagasse ashas an un-utilized and waste material .

After the extraction of all economical sugar from sugarcane, about 4045% fibrous residue is obtained, which is reused in the same industry as fuel in boilers for heat generation leaving behind 8 -10% ash as waste, known as sugarcane bagasse ash (SCBA).

The SCBA contains high amounts of un-burnt matter  silicon, aluminium and calcium oxides But the ashes obtained directly from the mill are not reactive because of these are burnt under uncontrolled conditions and at very high temperatures . The ash, therefore, becomes an industrial waste and poses disposal problems.

The bagasse ash used in the investigation is obtained from a Corporate Sugar Factory in the nearby vicinity. The sugarcane bagasse consists of approximately 50% of cellulose, 25% of hemicellulose and 25% of lignin. Each ton of sugarcane generates approximately 26% of bagasse (at a moisture content of 50%) and 0.62% of residual ash. The residue after combustion presents a chemical composition dominates by silicon dioxide (SiO2).

36 A study of alternative materials for cement and fine aggregate

https://www.sciencedirect.com/science/article/pii/S221260901530011X#b0245

http://www.rroij.com/open-access/experimental-study-on-use-of-sugar-canebagasse-ash-in-concrete-bypartiallyreplacement-with-cement.

https://www.irjet.net/archives/V4/i6/IRJET-V4I6471.pdf

 Test Methods (Jayminkumar A. Patel1 , Dr. D. B. Raijiwala2 P. G. Student, Department of Applied Mechanics, S. V. National Institute of Technology, Surat, Gujarat, India)

At the end of each curing period, a total of 3 specimens were tested for each concrete property. The compressive strength test was carried out on the 150mm cube specimens, whilst the split tensile strength test was carried out on the 150mm diameter and 300mm height cylindrical specimens as per Indian standard. Water absorption test were carried out to determine the sorptivity coefficient of concrete

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specimens, which were preconditioned in oven at 105ÂşC for 24 hr and then cooled down in desiccators for 24 hr to achieve a constant moisture level. Then, four sides of the concrete specimens were sealed by electrician tape to avoid evaporative effect as well as to maintain uniaxial water flow during the test and the opposite faces were left open. Before specimens were kept in water, their initial weights were recorded. One face of the specimen was in contact with water whilst the water absorption at predefined intervals was measured with a balance of 0.1gm readability.

The sorptivity coefficient can be calculated by the following expression: S = (Q/A) / t½ Results:

https://www.ijirset.com/upload/2015/april/77_Experimental.pdf

 Compressive Strength The results obtained from compressive strength test for all the mixes are given below. It can be seen that the compressive strength results of specimens at 10% replacement of SCBA were higher than those at 0% SCBA. Further increase in SCBA percentage results in decreasing compressive strength along with significant fall in properties offresh concrete. It is also indicated that the rate of increase of strength of mixes with SCBA is higher at later days that may be due to pozzolanic properties of SCBA.

38 A study of alternative materials for cement and fine aggregate

https://www.ijirset.com/upload/2015/april/77_Experimental.pdf

 Tensile strength The tensile strength results for all the mixes for 28 days curing are shown in fig.2. When the influence of SCBA on the tensile strength of concrete was examined, it was observed that the development of tensile strength of mixes decreases as the replacement of SCBA increases.

https://www.ijirset.com/upload/2015/april/77_Experimental.pdf

 Conclusion On the basis of experimental investigation carried out, the following conclusions can be drawn. (i) The fraction of fine aggregates i.e. 10% to 20% can be effectively replaced with a bagasse ash (untreated)

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without a considerable loss of workability and strength properties. (ii) The compressive strength results represent that, the strength of the mixes with 10% and 20% bagasse ash increases at later days (28 days) as compared to7 days that may be due to pozzolanic properties of bagasse ash. (iii) The Sorptivity test result shows that the sorptivity coefficient increases with increase in percentage of bagasse ash which indicate more permeable concrete that is due to porous nature of SCBA and the impurities in it. (iv) In its purest form the bagasse ash can prove to be a potential ingredient of concrete since it can be an effective replacement to cement and fine aggregate.

2.2.2 RICE HUSK ASH Rice husk is one of the fundamental agrarian wastes obtained from the external covering of rice grains amid the processing procedure.

https://www.irjet.net/archives/V4/i6/IRJET-V4I6471.pdf

The rice husk has no useful application and is treated as a waste material that creates the pollution problem (Givi et al., 2010).

Because of low nutrition property of rice husk, it is unsuitable and does not have edibility yet in a few nations, it has been utilized generally as fuel for rice plants and electric power plants as a compelling technique to reduce the volume of rice husk waste (Madandoust et al., 2011). Many researchers in the past had used rice husk ash as a cement replacement material in concrete (Givi et al., 2010; Madandoust et al., 2011; Zaid and Ganiyat, 2009). After colossal researches Iam and Makul (2013) tested the properties of selfcompacting concrete using rice husk and limestone as a fine aggregate replacement. It was reported that use of rice husk ash in self-compacting concrete reduced the unit weight, flowability, porosity, water absorption, compressive strength, ultrasonic pulse velocity and the cost. Shafigh et al. (2014) reported the use of rice husk as cement

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replacing material, fire making, litter material, marking the concrete, board production, as silicon carbide whiskers to reinforce ceramic cutting tools and aggregate replacement in concrete in low-cost housing. 

MATERIALS AND METHODS (Obilade, I.O. Department of Civil Engineering, Osun State Polytechnic, Iree, Nigeria)

The Rice Husk, granite (12mm size), sand, Ordinary Portland Cement and water Batching of materials was done by both weight and volume. The percentage replacements of Ordinary Portland cement (OPC) by Rice Husk Ash (RHA) were 0%, 5%, 10%, 15%, 20% and 25% by both weight and volume.

The concrete mix proportion was 1:2:4 by both weight and volume.

Cubic specimens of concrete with size 150 x 150 x 150 mm were cast for determination of all measurements. The concrete was mixed, placed and compacted in three layers. The samples were demoulded after 24 hours and kept in a curing tank for 7, 14 and 28 days as required.

The Compacting Factor apparatus was also used to determine the compacting factor values of the fresh concrete in accordance with BS 1881: Part 103 (1983).  Result : Compacting Factor

http://www.theijes.com/papers/v3-i8/Version-4/B038409014.pdf

The Compacting Factor of both mixes decreased with increase in the percentage replacement of sand by rice husk. This is due to the increase in the specific surface as a result of the increase in the quantity of Rice Husk, thereby requiring more water to make the specimens workable. The workability of the volume-batched concrete produced by volume replacement of sand by rice husk is higher than that produced by weight replacement. Since sand is denser than rice husk, replacement by an equal mass of rice husk leads to a larger increase in volume than replacement by an equal volume of sand.

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Increase in the quantity of rice husk increase the specific surface area, thereby more water would be required.  Bulk Densities of Concrete Cubes:

http://www.theijes.com/papers/v3-i8/Version-4/B038409014.pdf

http://www.theijes.com/papers/v3-i8/Version-4/B038409014.pdf

 Compressive Strength of Concrete Cubes :

42 A study of alternative materials for cement and fine aggregate

http://www.theijes.com/papers/v3-i8/Version-4/B038409014.pdf

 Observation: It can be observed that the compressive strength decreased as the rice husk content increased. The compressive strength is maximum at 0% replacement by rice husk and minimum at 25% replacement. As rice husk content increases, the specific area increases, thus requiring more cement paste to bond effectively with the husks. Since the cement content remains the same, the bonding is therefore inadequate. The compressive strength reduces as a consequence of the increase in percentage of sand.  Conclusion:

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(i) (ii) (iii)

There exists a high potential for the use of rice husk as fine aggregate in the production of lightly reinforced concrete.

Weight-Batched Rice Husk Concrete and Volume-Batched Rice Husk Concrete show similar trends in the variation of bulk density, workability and compressive strength.

Loss of bulk density, workability and compressive strength is higher for Weight-Batched Rice Husk Concrete than VolumeBatched Rice Husk Concrete.

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3.CONCLUSION While the world has come to rely on concrete as one of the main material for building construction, concrete could partially replace with other materials such as industrial and agricultural wastes, recyclable materials (rubber, plastic etc.)

The industrial and agricultural wastes are turned into a valuable by products and reduce the environmental pollution. Thus, all the wastes are having adequate strength and improved durability in their compressive strength and flexural strength in the concrete.

Thus, due to replacement we can utilized an industrial and agricultural wastes effectively also we can get a replacement approach towards natural material which are conventional it also shows the minimization the cost of concrete hence economy also achieved.

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CHAPTER 4 : References

46 A study of alternative materials for cement and fine aggregate

REFERENCES https://www.bca.gov.sg/SustainableConstruction/others/sc_materials_book.pdf https://inhabitat.com/11-green-building-materials-that-are-way-better-thanconcrete/ https://www.smartcitiesdive.com/ex/sustainablecitiescollective/five-sustainablebuilding-materials-could-transform-construction/17346/ https://www.nature.com/news/environment-waste-production-must-peak-thiscentury-1.14032 https://www.sciencedirect.com/science/article/pii/S2090447914001610 https://www.sciencedirect.com/science/article/pii/S2212609015301217 https://www.ncbi.nlm.nih.gov/pubmed/16406289 https://www.sciencedirect.com/science/article/pii/S1877705813000088 https://www.sciencedirect.com/science/article/pii/S221260901530011X http://ena.lp.edu.ua:8080/bitstream/ntb/16692/1/55-Stajanca-296-302.pdf http://ro.uow.edu.au/cgi/viewcontent.cgi?article=1013&context=wollgeo Ground granulated blast-furnace slag - Wikipedia, the free encyclopaedia http://www.ukcsma.co.uk/what_is_ggbs.html http://www.ecocem.ie/technical,working.htm http://ggbsreviewgroup.blogspot.in/ http://www.vcem-global.com/technical.html Venu Malagavelliet.al./International Journal of Engineering Science and Technology Vol. 2(10), 2010, 5107-511.

European Journal of Scientific Researsch ISSN 1450-216X Vol.88 No-1 October, 2012, pp.155163@Euro journals Publishing, Inc. 2012 http://www.europeanjournalof scientific research.com. https://www.ijirset.com/upload/2015/april/77_Experimental.pdf

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48 A study of alternative materials for cement and fine aggregate

CHAPTER number: Appendix

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APPENDIX