1. Construction Materials Lecture 1 - Introduction
CE 233 – Construction Materials
Construction Materials Lecture 1 - Introduction
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2. Introduction Historical Perspective
CE 233 – Construction Materials
Historical Perspective
Since the beginning of time, people have created shelter out of whatever was at hand. Caves were convenient ready made shelters and live in them. But after emerging from the caves shelters were constructed of wood, grasses, skins, stone and any other suitable readily available resources.
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3. Introduction
CE 233 – Construction Materials
A simple igloo can maintain a 70 degree (F’) temperature differential between the indoor and outdoor environment.
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4. Introduction
CE 233 – Construction Materials
TIPI
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5. Introduction
CE 233 – Construction Materials
Materials are so important in the development of civilization that we associate Ages with them. In the origin of human life on Earth, the Stone Age, people used only natural materials, like stone, clay, skins, and wood. When people found copper and how to make it harder by alloying, the Bronze Age started about 3000 BC. The use of iron and steel, a stronger material that gave advantage in wars started at about 1200 BC. The next big step was the discovery of a cheap process to make steel around 1850, which enabled the railroads and the building of the modern infrastructure of the industrial world.
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6. Introduction
CE 233 – Construction Materials
MUDS / BRICKS
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7. Introduction
CE 233 – Construction Materials
PUEBLOS
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8. GLASS Philip Johnsonn_Glass House
Introduction
CE 233 – Construction Materials
GLASS
Philip Johnsonn_Glass House
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9. Introduction
CE 233 – Construction Materials
WOOD
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10. IRON/STEEL Mies Van Der Rohe_Farnsworth House Plano/Illinois
Introduction
CE 233 – Construction Materials
IRON/STEEL
Mies Van Der Rohe_Farnsworth House
Plano/Illinois
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11. Introduction
CE 233 – Construction Materials
CAST IRON
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12. Introduction Materials Science and Engineering
CE 233 – Construction Materials
Materials Science and Engineering
Understanding of how materials behave like they do, and why they differ in properties was only possible with the atomistic understanding allowed by quantum mechanics, that first explained atoms and then solids starting in the 1930s. The combination of physics, chemistry, and the focus on the relationship between the properties of a material and its microstructure is the domain of Materials Science. The development of this science allowed designing materials and provided a knowledge base for the engineering applications .
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13. Introduction Structure:
CE 233 – Construction Materials
Structure:
At the atomic level: arrangement of atoms in different ways. (Gives different properties for graphite than diamond both forms of carbon.)
At the microscopic level: arrangement of small grains of material that can be identified by microscopy. (Gives different optical properties to transparent vs. frosted glass.)
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14. Introduction
CE 233 – Construction Materials
Properties are the way the material responds to the environment. For instance, the mechanical, electrical and magnetic properties are the responses to mechanical, electrical and magnetic forces, respectively. Other important properties are thermal (transmission of heat, heat capacity), optical (absorption, transmission and scattering of light), and the chemical stability in contact with the environment (like corrosion resistance).
Processing of materials is the application of heat (heat treatment), mechanical forces, etc. to affect their microstructure and, therefore, their properties.
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15. Introduction Why Study Materials Science ?
CE 233 – Construction Materials
Why Study Materials Science ?
To be able to select a material for a given use based on considerations of cost and performance.
To understand the limits of materials and the change of their properties with use.
To be able to create a new material that will have some desirable properties.
All engineering disciplines need to know about materials.
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16. Introduction Classification of Materials
CE 233 – Construction Materials
Classification of Materials
Like many other things, materials are classified in groups. One could classify them according to;
structure,
properties,
use.
According to the way the atoms are bound together:
Metals: valence electrons are detached from atoms, and spread in an 'electron sea' that "glues" the ions together. Metals are usually strong, conduct electricity and heat well and are opaque to light (shiny if polished). Examples: aluminum, steel, brass, gold.
Semiconductors: the bonding is covalent (electrons are shared between atoms). Their electrical properties depend extremely strongly on minute proportions of contaminants. They are opaque to visible light but transparent to the infrared.
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17. Introduction
CE 233 – Construction Materials
Ceramics: atoms behave mostly like either positive or negative ions, and are bound by Coulomb forces between them. They are usually combinations of metals or semiconductors with oxygen, nitrogen or carbon (oxides, nitrides, and carbides). Examples: glass, porcelain, many minerals.
Polymers: are bound by covalent forces and also by weak van der Waals forces, and usually based on H, C and other non-metallic elements. They decompose at moderate temperatures (100 – 400 C), and are lightweight. Other properties vary greatly. Examples: plastics (nylon, Teflon, polyester) and rubber.
Other categories are not based on bonding. A particular microstructure identifies composites, made of different materials in intimate contact (example: fiberglass, concrete, wood) to achieve specific properties.
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18. Introduction Modern Material's Needs CE 233 – Construction Materials
Engine efficiency increases at high temperatures: requires high temperature structural materials
Hypersonic flight requires materials that are light, strong and resist high temperatures.
Optical communications require optical fibers that absorb light negligibly.
Civil construction – materials unbreakable windows.
Structures: materials that are strong like metals and resist corrosion like plastics.
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19. Introduction Principles
CE 233 – Construction Materials
Principles
Cultural Context: Technology exists within a cultural context. Therefore, contemporary building technology derives of a rich historical and cultural evolution of technique and form that augments the ability to design intelligently.
Holistic Building: Understanding individual building components and the details necessitates understanding the guiding architectural intentions, performance requirements, process of manufacture and assembly, and systematic organization of various building assemblies.
Invention: Architectural invention is the medium for the determination of form at all scales and permeates the physical architectural result. The making of details is not a deterministic process that seeks to optimize a singular solution.
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20. Introduction Achievement in material science: 1900-1980
CE 233 – Construction Materials
Achievement in material science:
Polymers (sealants, coatings, membranes, adhesives, nonwoven fabrics)
Metals (especially thin films, Low-e glass) Composites: FRPs, GFRP, CFRP
Digital Technologies: CAD/CAM, Simulation Software, Project Management, etc.
Cable net and Fabric Structures (with limited use)
Efforts for Future
Modular Building (except at the very low end of the market)
Concrete Shells and Hyperbolic Paraboloids (new morphologies)
“Fordist” Mass production and assembly
High Performance composites (that is, carbon and glass reinforced materials)
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21. Drivers for Innovation Now Global Economy
CE 233 – Construction Materials
Drivers for Innovation Now
Global Economy
Competition and Alliances across sovereign borders
New Markets (esp. China, rest of Asia, and former Soviet Republics)
Sustainable Strategies Energy Efficiencies
Materials Acquisition and Processing (Resource Efficiencies)
End of Life Materials Reuse (Life Cycle Costing)
Technological Advance
Improved Technology Transfer (Process Engineering, simulation technologies, Management Technologies etc.)
Materials Science
Digital Technologies
Materials
The integration of various materials together into pre-manufactured assemblies and composites
Specification by performance
Processes
Removing as much specialized “expertise” (knowledge) from the construction site as possible
Morphologies
Inventing new forms that use materials more efficiently and employ time-saving construction methods
Integrating building systems together in a synergistic way
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22. Introduction Obstacles for Innovation:
CE 233 – Construction Materials
Obstacles for Innovation:
“Fragmented” structure of the construction industry
“Fragmented” process in the industry namely;
Design: numerous consultants and project components
Construction: numerous trades/subcontractors
Relatively Low R&D investment by construction related Industries
Continuing underestimation of the level of investment necessary for “real” innovation, proof of concept and market entry
Continuing disciplinary specialization of the various scientific, professional and business interests all involved in the construction process
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23. Introduction Obstacles for Innovation (cnt):
CE 233 – Construction Materials
Obstacles for Innovation (cnt):
Average time period necessary for a technical advance (from lab) to reach market = 17 years in the U.S.
• For every $1 of laboratory research conducted, $10 must by spent for proof of concept and product development and,
$100 dollars must be spent for industrial retooling and market entry.
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24. Introduction Obstacles for Innovation (cnt): Energy
CE 233 – Construction Materials
Obstacles for Innovation (cnt):
Energy
Total energy use for buildings in developed nations at an historical high.
Overwhelming reliance on fossil, nonrenewable fuels.
Little domestic incentive to reduce energy consumption by buildings.
Little domestic incentive to increase material use efficiency.
Facts:
Buildings now account for 1⁄2 of energy consumption in the western world.
Buildings now account for 1/3 of energy consumption in the entire world.
3⁄4 of the world’s energy output is consumed by 1⁄4 of the world’s population.
Transport
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25. Introduction Why do we Need Buildings?
CE 233 – Construction Materials
Why do we Need Buildings?
We build because little that we do can take place outdoors. We need shelter from sun, wind, rain, and snow. We need dry, level platforms for our activities. Often we need to stack these platforms to multiply available ground space. On these platforms, and within our shelter, we need air that is warmer or cooler, more or less humid, than outdoors. We need less light by day, and more light by night, than is offered by the natural world. We need services that provide energy, communications and water and disposal of wastes. So we gather materials and assemble them into the constructions we call buildings to satisfy these needs.
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26. Introduction Building Systems 1. Foundation/Subgrade (SITE)
CE 233 – Construction Materials
Building Systems
1. Foundation/Subgrade (SITE)
2. Superstructure (STRUCTURE)
3. Exterior Envelope (SKIN)
4. Interior Partitions (SPACE
PLAN)
5. Mechanical Systems
(SERVICES) 6. Furnishings (STUFF)
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27. Introduction Cost over time 1. Foundation/ Subgrade structure 10%
CE 233 – Construction Materials
Cost over time
1. Foundation/ Subgrade structure 10%
2. Structure (superstructure) 30-40%
3. Exterior Wall 10-20%
4. Interior Partitions 10%
5. Mechanical Devices 30-40%
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28. Introduction Lifetimes Years Foundation/Subgrade 50-100+
CE 233 – Construction Materials
Lifetimes Years
Foundation/Subgrade
Superstructure 50+
Exterior Wall 25+
Interior Partitions 10-30
Mechanical Devices 20
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29. Introduction Performance Requirements
CE 233 – Construction Materials
Performance Requirements
1. Foundation/ Subgrade structure
i Dead and live load transfer
2. Superstructure
Dead and Live load transfer
Lateral force resistance and stability
3. Exterior Wall
i Maintenance of interior environment
4. Interior Partitions
i Programmatic spatial definition
ii Acoustic separation
5. Mechanical Devices
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30. Introduction
CE 233 – Construction Materials
A wide range of building materials is available for the construction of buildings and structures. The proper selection of materials to be used in a particular building or structure can influence the original cost, maintenance, ease of cleaning, durability and, of course, appearance.
Materials science has now advanced far beyond the levels of knowledge which existed at the great periods of historical building, but the performance and characteristics of materials which people in the building industry need to know about are still much the same and can be identified as primarily those pertaining to:
(a) resistance to structural stress (b) process of manufacture (c) effects of water, freezing and thawing, and atmosphere
(d) heat and temperature effects on material/product (e) effects of ultra-violet radiation (f) electrolytic or other special characteristics (g) acoustic properties.
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31. Introduction
CE 233 – Construction Materials
Namely, Six General Physical Performance Mandates of Buildings
Spatial Performance
Thermal Performance
Air Quality
Acoustical Performance
Visual Performance
Building Integrity
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32. Introduction Constraints to Choosing Building Systems
CE 233 – Construction Materials
Constraints to Choosing Building Systems
General physical limitations: Land area available for building, weight of building and soil strength, structural dimensions, material performance under exposure conditions, contractual arrangements regarding building construction.
Material selection dependent on: Designer/Architect with inputs from owner (for appearance and performance) and contractor (for cost, availability & constructability)
Budget - Permitted and overruns
Zoning ordinances: Imposed by local authorities (Planning Department - Residential or industrial, area covered by and offsets required for building, parking spaces, floor area, height of building, center-city fire zones, etc.
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33. Introduction Constraints to Choosing Building Systems
CE 233 – Construction Materials
Constraints to Choosing Building Systems
Health codes : Occupational health and safety
Fire codes
Plumbing codes
Electrical codes
Building Contractors’ and Labor Unions’ Regulations
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34. Introduction Sustainability
CE 233 – Construction Materials
Sustainability
“…meeting the needs of the present generation without compromising the ability of future generations to meet their needs.”
Sustainable Design & Construction Actions
Energy efficient buildings
Re-use existing structures
Efficient land use
Use of renewable products / materials
Protect soil and water resources
Reduce / eliminate pollution
Sustainability - addressed on a Life Cycle basis
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35. Introduction Factors Influencing Selection of a Construction Material
CE 233 – Construction Materials
Factors Influencing Selection of a Construction Material
A wide range of construction materials is available. The proper selection of materials to be used in a particular construction project depends on the following factors
Strength - mukavemet
Availability - mevcut malzeme
Durability - dayanıklılık
Workability - işlenebilirlik
Ease of Transportation - ulaşım kolaylığı
Cost - bütçe
Aesthetics - estetik
Resistance to Fire - yangına direnç
Ease of Cleaning - temizleme kolaylığı
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36. Introduction Factors Influencing Economy of a Construction Material
CE 233 – Construction Materials
Factors Influencing Economy of a Construction Material
Availability of Material
Cost of Raw Materials (Cost of Unprocessed Material)
Manufacturing Costs (Cost of Processed Material)
Transportation Cost
Cost of Placing
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37. Introduction High Performance Materials
CE 233 – Construction Materials
High Performance Materials
The increasing scope of civil engineering has brought many researches and advancement in materials and knowledge of molecular structure. These materials have shown better quality with much safety and economy. Such materials are known as High Performance Materials. In addition, improvements have been made to existing materials by changing their molecular structures or including additives to improve quality, economy, and performance.
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38. Introduction Advantages of High Performance Materials
CE 233 – Construction Materials
Advantages of High Performance Materials
High strength concrete can be produced
Elastomeric material are used in joints in highly active earthquake areas
Light weight concrete and aggregate have made cross sections smaller
Polymers have been mixed with asphalt, allowing pavements to last longer under the effect of vehicle loads and environmental conditions.
Fiber-Reinforced Concrete has greater toughness than conventional portland cement.
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39. Introduction PHYSICAL PROPERTIES of Construction Materials
CE 233 – Construction Materials
PHYSICAL PROPERTIES of Construction Materials
Weathering Resistance is the ability of a material to endure alternate wet and dry conditions for a long period without considerable deformation and loss of mechanical strength.
Water Permeability is the capacity of a material to allow water to penetrate under pressure. Materials like glass, steel and bitumen are impervious.
Frost Resistance denotes the ability of a water-saturated material to endure repeated freezing and thawing with considerable decrease of mechanical strength. Under such conditions the water contained by the pores increases in volume even up to 9 per cent on freezing. Thus the walls of the pores experience considerable stresses and may even fail.
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40. Introduction
CE 233 – Construction Materials
Heat Conductivity is the ability of a material to conduct heat. It is influenced by nature of material, its structure, porosity, character of pores and mean temperature at which heat exchange takes place. Materials with large size pores have high heat conductivity because the air inside the pores enhances heat transfer. Moist materials have a higher heat conductivity than drier ones. This property is of major concern for materials used in the walls of heated buildings since it will affect dwelling houses.
Thermal Capacity is the property of a material to absorb heat described by its specific heat. Thermal capacity is of concern in the calculation of thermal stability of walls of heated buildings and heating of a material.
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41. Introduction
CE 233 – Construction Materials
Fire Resistance is the ability of a material to resist the action of high temperature without any appreciable deformation and substantial loss of strength. Fire resistive materials are those which char, smoulder, and ignite with difficulty when subjected to fire or high temperatures for long period but continue to burn or smoulder only in the presence of flame,
Non-combustible materials neither smoulder nor char under the action of temperature. Some of the materials neither crack nor lose shape such as clay bricks, whereas some others like steel suffer considerable deformation under the action of high temperature.
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42. Introduction
CE 233 – Construction Materials
Refractoriness denotes the ability of a material to withstand prolonged action of high temperature without melting or losing shape. Materials resisting prolonged temperatures of 1580°C or more are known as refractory.
High-melting materials can withstand temperature from 1350–1580°C, whereas low-melting materials withstand temperature below 1350°C.
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43. Introduction
CE 233 – Construction Materials
Chemical Resistance is the ability of a material to withstand the action of acids, alkalis, sea water and gases. Natural stone materials, e.g. limestone, marble and dolomite are eroded even by weak acids, wood has low resistance to acids and alkalis, bitumen disintegrates under the action of alkali liquors.
Durability is the ability of a material to resist the combined effects of atmospheric and other factors.
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44. Introduction MECHANICAL PROPERTIES
CE 233 – Construction Materials
MECHANICAL PROPERTIES
The important mechanical properties considered for building materials are: strength, compressive (sıkıştırma) , tensile (gerilme), bending (bükülme), impact, hardness (sertlik), plasticity (plastisite), elasticity (esneklik) and abrasion (aşınma) resistance.
The common characteristics of building materials under stress are
ductility, süneklik
brittleness, kırılganlık
stiffness, sertlik
flexibility, esneklik
toughness, dayanıklılık
malleability şekil verilebilirlik
hardness. sertlik
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45. Introduction
CE 233 – Construction Materials
Strength is the ability of the material to resist failure under the action of stresses caused by loads, the most common being compression, tension, bending and impact. The importance of studying the various strengths will be highlighted from the fact that materials such as stones and concrete have high compressive strength but a low (1/5 to 1/50) tensile, bending and impact strengths.
Elasticity is the ability of a material to restore its initial form and dimensions after the load is removed. Within the limits of elasticity of solid bodies, the deformation is proportional to the stress. Ratio of unit stress to unit deformation is termed as modulus of elasticity. A large value of it represents a material with very small deformation.
Plasticity is the ability of a material to change its shape under load without cracking and to retain this shape after the load is removed. Some of the examples of plastic materials are steel, copper and hot bitumen.
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46. Introduction
CE 233 – Construction Materials
Hardness is the ability of a material to resist penetration by a harder body. Hard materials resist scratching and denting, for example cast iron and chrome steel. Materials resistant to abrasion.
The ductile materials can be drawn out without necking down, the examples being copper and wrought iron.
Brittle materials have little or no plasticity. They fail suddenly without warning. Cast iron, stone, brick and concrete are comparatively brittle materials having a considerable amount of plasticity.
Stiff materials have a high modulus of elasticity permitting small deformation for a given load.
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47. Introduction
CE 233 – Construction Materials
Flexible materials have low modulus of elasticity and bend considerably without breakdown. Tough materials withstand heavy shocks.
Toughness depends upon strength and flexibility.
Malleable materials can be hammered into sheets without rupture. It depends upon ductility and softness of material. Copper is the most malleable material.
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48. Introduction Construction Materials:
CE 233 – Construction Materials
Construction Materials:
Many naturally occurring substances, such as clay, sand, wood and rocks, even twigs and leaves have been used to construct buildings. Apart from naturally occurring materials, many man-made products are in use, some more and some less synthetic. The manufacture of building materials is an established industry in many countries and the use of these materials is typically segmented into specific specialty trades, such as carpentry, plumbing, roofing and insulation work. They provide the make-up of habitats and structures including homes.
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49. Introduction
CE 233 – Construction Materials
Fabric : The tent used to be the home of choice among nomadic groups the world over. Two well known types include the conical teepee and the circular yurt. It has been revived as a major construction technique with the development of tensile architecture and synthetic fabrics. Modern buildings can be made of flexible material such as fabric membranes, and supported by a system of steel cables.
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50. Introduction
CE 233 – Construction Materials
Mud and clay : The amount of each material used leads to different styles of buildings. The deciding factor is usually connected with the quality of the soil being used. The other main ingredients include more or less sand/gravel and straw/grasses. Rammed earth is both an old and newer take on creating walls, once made by compacting clay soils between planks by hand, now forms and mechanical pneumatic compressors are used.
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51. Introduction
CE 233 – Construction Materials
Soil and especially clay is good thermal mass; it is very good at keeping temperatures at a constant level. Homes built with earth tend to be naturally cool in the summer heat and warm in cold weather. Clay holds heat or cold, releasing it over a period of time like stone. Earthen walls change temperature slowly, so artificially raising or lowering the temperature can use more resources than in a wood built house, but the heat/coolness stays longer.
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52. Introduction
CE 233 – Construction Materials
Rock : Rock structures have existed for as long as history can recall. It is the longest lasting building material available, and is usually readily available. There are many types of rock through out the world all with differing attributes that make them better or worse for particular uses. Rock is a very dense material so it gives a lot of protection too, its main draw-back as a material is its weight and awkwardness.
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53. Introduction
CE 233 – Construction Materials
Stone walls have been built for as long as humans have put one stone on top of another. Eventually different forms of mortar were used to hold the stones together, cement being the most commonplace now.
Mostly stone buildings can be seen in most major cities, some civilizations built entirely with stone such as the Pyramids in Egypt, the Aztec pyramids and the remains of the Inca civilization.
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54. Introduction
CE 233 – Construction Materials
Cement: In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. Cement used in construction is characterized as hydraulic or non-hydraulic. Hydraulic cements (e.g., Portland cement) harden because of hydration, chemical reactions that occur independently of the mixture's water content; they can harden even underwater or when constantly exposed to wet weather. The chemical reaction that results when the anhydrous cement powder is mixed with water produces hydrates that are not water-soluble. Non-hydraulic cements (e.g., lime and gypsum plaster) must be kept dry in order to retain their strength.
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55. Introduction
CE 233 – Construction Materials
Cement is made by heating limestone (calcium carbonate) with small quantities of other materials (such as clay) to 1450 °C in a fire stove, in a process known as calcination, whereby a molecule of carbon dioxide is liberated from the calcium carbonate to form calcium oxide, or quicklime, which is then blended with the other materials that have been included in the mix. The resulting hard substance, called 'clinker', is then ground with a small amount of gypsum into a powder to make 'Ordinary Portland Cement', the most commonly used type of cement (often referred to as OPC).
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56. Introduction
CE 233 – Construction Materials
Portland cement is a basic ingredient of concrete and mortar. The most common use for Portland cement is in the production of concrete. Portland cement may be grey or white.
The most important use of cement is the production of mortar and concrete—the bonding of natural or artificial aggregates to form a strong building material that is durable in the face of normal environmental effects.
Concrete should not be confused with cement, because the term cement refers to the material used to bind the aggregate materials of concrete. Concrete is a combination of a cement and aggregate.
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57. Introduction
CE 233 – Construction Materials
Concrete: Concrete is a composite building material made from the combination of aggregate and a binder such as cement. The most common form of concrete is Portland cement concrete, which consists of gravel, sand , portland cement and water. After mixing, the cement hydrates and eventually hardens into a stone-like material.
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58. For a concrete construction of any size, as concrete has a rather low tensile strength, it is generally strengthened using steel rods or bars. This strengthened concrete is then referred to as reinforced concrete. In order to minimise any air bubbles, that would weaken the structure, a vibrator is used to eliminate any air that has been entrained when the liquid concrete mix is poured around the ironwork. Concrete has been the predominant building material in this modern age due to its longevity, formability, and ease of transport. Recent advancements, such as Insulating concrete forms, combine the concrete forming and other construction steps. All materials must be taken in required proportions as described in standards. For concrete the ratio of cement: sand: gravel is 1 : 2 : 3. For wall construction the ratio of cement to sand ratio is 1 : 6. For plastering the ratio of cement to sand is 1:4. In any case the mixture should be used with in 3 to 4 hours for best results.
CE 233 – Construction Materials
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59. Introduction
CE 233 – Construction Materials
Metal: Metal is used as structural framework for larger buildings such as skyscrapers, or as an external surface covering. There are many types of metals used for building. Steel is a metal alloy whose major component is iron, and is the usual choice for metal structural building materials. It is strong, flexible, and if refined well and/or treated lasts a long time. Corrosion is metal's prime enemy when it comes to longevity.
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60. Introduction
CE 233 – Construction Materials
Metal figures quite prominently in prefabricated structures such as the semi cylindrical hut. It requires a great deal of human labor to produce metal, especially in the large amounts needed for the building industries.
Other metals used include titanium, chrome, gold, silver. Titanium can be used for structural purposes, but it is much more expensive than steel. Chrome, gold, and silver are used as decoration, because these materials are expensive and lack structural qualities such as tensile strength or hardness.
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61. Introduction
CE 233 – Construction Materials
Glass: Glassmaking is considered an art form. Clear windows have been used since the invention of glass to cover small openings in a building. They provided humans with the ability to both let light into rooms while at the same time keeping inclement weather outside. Glass is generally made from mixtures of sand and silicates, in a very hot fire stove and is very brittle. Very often additives are added to the mixture when making to produce glass with shades of colors or various characteristics.
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62. Introduction
CE 233 – Construction Materials
The use of glass in architectural buildings has become very popular in the modern culture. Glass "curtain walls" can be used to cover the entire facade of a building, or it can be used to span over a wide roof structure in a "space frame". These uses though require some sort of frame to hold sections of glass together, as glass by itself is too brittle and would require an overly large fire stove to be used to span such large areas by itself.
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63. Introduction
CE 233 – Construction Materials
Cement composites: Cement bonded composites are made of hydrated cement paste that binds wood or alike particles or fibers to make pre-cast building components. Various fiberous materials including paper and fiberglass have been used as binders.
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