PART 1
Introduction to Construction Materials & Testing
Learning Objectives:
Upon completion of PART 1, you will be able to:
1. Introduce the basic concept of Construction Materials and Testing.
2. Identify the importance of Construction Materials and Testing to the industry.
Learning Materials:
1. Laptop / Personal Computer / Cellphone / Tablet
2. Copy of Introduction to Construction Materials and Testing Module
3. LCD Projector (for Faculty use only during lectures)
By: ENGR.CRS2021
4. Calculator
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PART 1
Introduction to Construction Materials & Testing
LESSON 1: Introduction and Basic Concepts
Engineering structures are composed of materials. These materials are known as
engineering materials or materials of construction. It is necessary for the civil engineer to
become conversant with the properties of such materials.
The service conditions of buildings demand a wide range of materials and various
properties such as water resistance, strength, durability, temperature resistance, appearance,
permeability, etc. They are to be properly studied before making final selection of any building
material for a particular use.
LESSON 2: Classification of Engineering Material
The factors which form the basis of various systems of classifications of materials in
material science and engineering are:
i. The chemical composition of the material;
ii. The mode of occurrence of the material in nature;
iii. The refining and manufacturing processes to which the material was subjected prior to
the acquisition of the required properties;
iv. The atomic and crystalline structure of material; and
v. The industrial and technical use of the material
1. Metals (ferrous and non-ferrous) and alloys
2. Ceramics - Structural, pipes, including bricks, roof tiles & floor
3. Polymers - a substance that has a molecular structure consisting chiefly or entirely of
a large number of similar units bonded together, e.g., many synthetic organic materials
used as plastics and resins
4. Composites - Concrete is a composite of aggregate, cement, additives and water. Disc
brake pads are composites of hard ceramic particles embedded in soft metal. The
polymer binds the reinforcement & particulate together. Polymer matrix composites are
lighter than steel, aluminum, concrete and brick.
5. Advanced materials
5.1. Translucent concrete. Mixed with glass fiber optical strands to create a solid
but sheer block. LitraCon, as the concrete is known, can be used in flooring
and pavement.
5.2. SensiTile. The concrete of the tiles is embedded with acrylic fiber-optic
channels that transfer light from one point to another. As shadows move
across Terrazzo’s surface, the light channels flicker with a randomized
twinkling effect.
5.3. Electrified wood. Two metal layers are pressed between the wood of the
furniture, making it possible to pass an electrical current through the whole
thing. The 12-volt power is fed to the metal layers via one connector and
lamps and other devices can be connected via the other.
By: ENGR.CRS2021
Common engineering materials that fall within the scope of material science and
engineering may be classified into one of the following five groups:
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Introduction to Construction Materials & Testing
5.4. Flexicomb. A flexible honeycomb matrix, which can be used to build lighting
fixtures, furniture and sculpture installations.
5.5. RichLite. A counter-top made of 70% recycled paper. The countertops are
made by treating paper with resin, and then baking it to create solid sheets.
Richlite was first used in aerospace, boating, and sports industries as
reinforcement for surfaces like fiberglass, but not is available for architectural
purposes as well.
5.6. Self-repairing cement. This cement is mixed with microcapsules that
release a glue-like epoxy resin that will automatically repair any cracks that
form in the sidewalk or roadway. In addition this cement will have the ability
to regulate heat. Phase-change materials that can absorb or release large
amounts of heat have also been included in the ingredients.
5.7. Carbon fiber. An extremely strong, lightweight material. It’s five times as
strong as steel, two times as stiff, yet weighs about two-thirds less. Made up
of carbon strands that are thinner than human hair. The strands can be woven
together, like cloth and then can be molded to any shape you might want.
5.8. Liquid Granite. It has the ability to completely replace cement in concrete.
The material is lightweight and has the same load bearing capacity of cement,
but is made of recycled materials.
5.9. Bendable concrete. This new concrete is around 500 times more resistant
to cracking than regular concrete thanks to the tiny fibers, which account for
two percent of its make-up. The fibers slide within the concrete when bending
occurs, providing it with enough give to prevent breakage.
5.10. Concrete canvass. Concrete canvass is a flexible cement impregnated
fabric that hardens on hydration to form a thin, durable water proof and fire
proof concrete layer. Essentially, it’s concrete on a roll just add water.
5.11. Low-E glass/films. Low-emissive (Low E) glass is window glass that has
been treated with an invisible metal or metallic oxide coating, creating a
surface that reflects heat, while allowing light to pass through. Windows
treated with Low-E coatings are proven to reduce energy consumption,
decrease fading of fabrics, such as window treatments, and increase overall
comfort in your home.
5.12. Transparent Aluminum. Extremely durable crystalline material with
excellent optical transparency used in windows, domes, plates, rods, and
tubes in a wide range of sizes and thicknesses.
5.13. Paper Insulation. Made from recycled newspapers and cardboard, is a
superior alternative to chemical foams. Both insect resistant and fireretardant due to the inclusion of borax, boric acid, and calcium carbonate.
It is possible to classify material properties as follows:
1. Physical properties. A material undergoes transition under the influence of
temperature and pressure, and these changes are physical in nature, because their
molecules remain intact. [Density, specific gravity, porosity, water absorption, etc…]
By: ENGR.CRS2021
LESSON 3: Properties of Engineering Materials
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PART 1
Introduction to Construction Materials & Testing
2. Mechanical properties. It is the property of material which opposes the deformation
or breakdown of material in presence of external forces or load. [tensile strength,
compressive strength, rigidity, hardness, creep, fatigue, etc…]
3. Thermal properties. The properties of a material which is related to its conductivity of
heat. These are the properties which are exhibited by a material when heat is passed
through it.
4. Chemical properties. A chemical property is any of a material’s properties that
becomes evident during, or after, a chemical reaction; that is, any quality that can be
established only by changing a substance’s chemical identity. Chemical properties
cannot be determined just by viewing or touching the substance; the substance’s
internal structure must be affected greatly for its chemical properties to be investigated.
[resistance to acids, alkalis, brine, and oxidation].
5. Economic characteristics. Cost saving characteristics.
6. Aesthetic properties. The qualities that make a product attractive to look at, or
pleasing to experience. [color, surface smoothness, the reflection of light, etc…]
LESSON 4: Physical Properties of Materials
Density, 𝛒
It is defined as mass per unit volume for a material in kg/m3.
ρ=
M
V
where
M = material mass
V = material volume
Relative density, d, is the ratio of the density of the material with pure water at 4℃.
d=
ρmaterial
ρ4℃ water
Two types of density are as follows:
1. Bulk density, 𝛒𝐛
It is the ratio of material mass to total volume of material including spaces.
ρb =
M Ms + Mw
=
V
Vs + Vv
Ms = solid mass
Mw = water mass
Vs = volume of solids
Vv = volume of voids
By: ENGR.CRS2021
where
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PART 1
Introduction to Construction Materials & Testing
Materials
Bulk density
(kg/m3)
Materials
Bulk density
(kg/m3)
Brick
1700
Steel
7850
Mastic Asphalt
2100
Aluminum
2700
Cement: Sand
2306
Copper
9000
Glass
2520
Lead
11340
Concrete 1:2:4
2260
Hardwood
769
Limestone
2310
Softwood, Plywood
513
Granite
2662
2. Solid density, 𝛒𝐬
It is the ratio of the mass of solid material to the volume of solid material
without any space.
ρs =
Ms
Vs
Unit Weight, 𝛄
It is the ratio of material’s weight to material’s volume.
γ=
W
V
where
W = weight (N)
V = volume (m3)
or
γ = ρg
Specific Gravity, 𝐆𝐬
It is the ratio of solid density of material and density of distilled water at a temperature of
4℃.
ρs
ρw
Porosity, 𝐧
It is the ratio of the volume of the spaces in the material to the overall volume.
n=
Vv
V
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Gs =
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PART 1
Introduction to Construction Materials & Testing
Void ratio, 𝐞
It is the ratio between the size of the voids to the volume of solid material.
e=
Vv
Vs
Water Absorption, 𝐖𝐖 or 𝐖𝐯
It denotes the ability of the material to absorb and retain water. It is expressed as
percentage in weight or of volume of dry material.
Ww =
Ms − M
(100%)
M
Wv =
Ms − M
(100%)
V
where
Ms = mass of the saturated material
M = mass od dry material
V = volume of material including pores
Water absorption by volume is always less than 100%, whereas that by weight of
porous material may exceed 100%.
The properties of building materials are greatly influenced when saturated. The
ratio of compressive strength of material saturated with water to that in dry state is known
as coefficient softening and describes the water resistance of materials. For materials like
clay which is soaked readily, it is zero, whereas for materials like glass and metals, it is 1.
Materials with coefficient softening less than 0.8 should not be recommended in the
situations permanently exposed to the action of moisture.
Weathering Resistance
It is the ability of a material to endure alternate wet and dry conditions for a long period
without considerable deformation and loss of mechanical.
Water Permeability
It is the capacity of a material to allow water to penetrate under pressure. Materials like
glass, steel and bitumen are impervious.
It 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 percent on freezing.
By: ENGR.CRS2021
Frost Resistance
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PART 1
Introduction to Construction Materials & Testing
LESSON 5: Mechanical Properties
The properties which relate to material behavior under applied forces define as mechanical
properties.
Strength
It is the ability of the material to resist failure under the action of stresses caused by loads.
Stress, 𝛔
It is the applied force P divided by the original area Ao .
σ=
P
Ao
There are several types of stress which depend on types of applied load. These stresses
can be classified as:
a.
b.
c.
d.
e.
Compression stress
Tension stress
Shear stress
Bending stress
Torsion stress
When bar is stretched, stresses are tensile (taken as positive).
If forces are reversed, stresses are compressive (negative).
Strain, 𝛆
It is the change in length δ divided by the original length Lo .
=
δ
Lo
When bar is elongated, strains are tensile (positive). When bar shortens, strains are
compressive (negative)
i.
ii.
iii.
iv.
Know the sources of construction materials;
Identify and know the properties of various construction materials;
Know how the materials are tested as per ASTM standards;
Know how to choose proper material from the commercially available varieties for a
particular purpose of construction;
v. Know common defects in the materials;
vi. Know various precautions to be taken while constructing for better durability.
By: ENGR.CRS2021
LESSON 6: Importance of the Study of Construction Materials
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