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What are the Construction materials?
The different types of materials used in the construction industry such as Stone, Bricks, Cement, aggregate, Lime, Mortar, Timber, Steel, Paint, Plumbing, Electrical, Varnish, Plastics, Glass, Tiles, etc… and Other insulation materials are called construction materials.
Stone
The stone is derived from Rocks which form the earth’s crust and have no definite shape or size. That is called natural materials.
The crushing strength of Good Building Stone is not less than 100kg/cm2.
The Crushing Strength of Building stone is always 1000 kg/cm2.
Stone | Heavey stone | Light stone | Soft stone |
Suitable | Retaining wall | Masonry Wall | ornamental work |
Classification of Stone/Rocks
Based on Formation/ Geological Classification
Ingenious Rock
Igneous Rocks are formed by the solidification of molten mass of silicates below or at the surface of the earth. Which is formed by the cooling of magma. For example: syenite, gabbro.
Main Constitutent- Silica
Intrusive Rocks are formed by the cooling of magma below the surface of the earth. It is two types:
Plutonic Rock | Depth 3- 8 km | Granite | Pegmatite |
Hypabyssal Rock | Depth 2-3 km | dolerite | diorite |
Extrusive Rock: If the cooling of magma at the surface of the earth. This rock is also called volcanic rock. For example: basalt, obsidian, trap, pumice, dacite.
Sedimentary Rock
Sedimentary rocks are formed by the Gradual deposition of material. like sand, silt, clay, and debris, etc.
Main Constitution: sand, silt, clay, debris, gravel etc.
It is also known as aqueous rock. The process of formation of the rock is petrification.
They are also satisfied due to the nature of this rock formation. This rock is formed in layers of materials. For example: Limestone, sandstone, gypsum, chalk, dolomite, kankar, conglomerate rock, diatomite, tripoli, chert etc.
Metamorphic rock
Metamorphic rocks are formed by the change in texture or mineral compaction or both of igneous or sedimentary rock due to high temperature and heavy pressure. For example: Marble, gneiss, quartzite, slate, schist, serpentine.
Main constitution: Ignious rock and sedimentry rock.
Igneous or sedimentary rock | Metamorphic Rock |
Granite | Genesis |
Sand Stone | Qurtezite |
Shale | Slate and schist |
Limestone and dolomite | Marble |
Canglomerate | Genesis |
Physical Classification
Stratified Rock
Stratified rocks are those which give distinct layers which can be separated. for ex all the sedimentary rock, marble, and quartzite.
Unstratified rock
Unstratified rocks do not show signs of strata and can’t be easily split into slabs. For eg, all igneous rocks.
Foliated rock
Foliated rocks tend to split in a certain direction. For eg, all metamorphic rocks but marble and quartzite are excluded.
Chemical Classification
Rock | Main Constituent | Example |
Argillaceous | Clay or alumina | Slate, Laterite, Koatine |
Silicious | Silica | granite, genesis, basalt, sand stone, quartizite |
Calcareous | lime or calcium oxide | Siliceous |
Characteristics of Good Building Stone
- Appearance and Colour
- Wight
- Water absorption less than 5%
- Fire resistance
- Electrical resistance
- Hardness
- Easy to working
- Durability
- Toughness
- Soluble salt of 0%
- Minimum crushing strength is 100 kg/cm2.
- Specific Gravity is not less than 2.4.
- Heaviness
Test of stone
Test of Stone | Used |
Absorption | To determine the amount of water absorbed in 24 hr. |
Acid Test | To check whether resistance |
Crushing Test | To determine the strength of the stone. |
Hardness Test | To determine the hardness of the stone |
Impact Test | To determine the toughness of the stone |
Smith Test | To find dirty materials in stone |
Attrition Test | To check resistance to abrasion |
Brard Test | For Frost resistance |
Microscope Test | Find out grain size, and existing of pores. |
Important Terms of Stone
Quarrying
The process of removing stone from the natural rock is known as quarrying. The open part of the natural rock from which useful materials are obtained is known as a quarry.
Quarry Sap
The process of removing quarry sap from stone is called seasoning of stone. Which process is complete within 6-12 months. Tool for quarrying pick axes, crowbar, Jumper, wedge, etc.
Method of Quarrying
Now we discuss what are the methods of stone quarrying. There are many types of methods used for stone quarrying. But, I have discussed it from a Technical terms point of view.
Digging or Excavation
It is carried out with the help of a tool such as a pick axe, Crowbat, hammer, shovel, etc. The tools are useful for the soft stone.
Heating
The top surface of the rock is heated by placing wood with fuel on it. Fire will be allowed for some hours. Then after heated which separated from the rock.
Wedging
This method is applicable when the rock contents cracks or joints on it. steel wedges or steel points are put in those cracks and hit with a hammer.
Blasting
In this method, explosives are used to separate the stone from the parent rock. This method is used when rock is hard and without any cracks.
The holes are drilled in the rock and explosives are arranged in the holes and blasted with proper safety.
Tools for blasting
- Steel jumper of 1.8- 3 m long and 40 diameter with chisel.
- Tamping needle.
- Scraping spoon
Explosives used in blasting are gun-power, Dynamite, Guncotton, Cordite, etc.
Gunpowder is not used for blasting underwater.
Dressing
It is the process of giving proper shape, size, and Finish. It is done either manually or mechanically. Artificial Stone is made of cement and natural aggregate with the required shape and size.
Tools used in dressing
- Soft stone chisel
- Crwo chisel
- Punch chisel
- Drafting Chisel
- Mason Hammer
- Scrubbing Hammer
- Fare Hammer
- Spalling hammer
Minerals in Rock
Minerals may be defined as Organic substances, Having usually have a definite chemical composition that can be expressed by a chemical formula and physical properties.
The properties of rock mainly depend on the types of minerals present in rock. For eg, Quartz, Felspet, Calcite, alumina and, Mica.
Properties of Minerals
- Cleavage Tendency of Minerals to break with smooth flat surface.
- Texture Arrangement Constituent mineral grain is available in stone.
- Luster Shine Surface of mineral. It appears under reflected light.
- Color is the main characteristic of minerals.
- Streak color of powder form of minerals.
- Weathering effect of atmospheric condition.
Moho’s Scales
It was created in 1812 by the German geologist and mineralogist Friedrich Moho. That is used to determine the hardness of stone.
Moho’s Scale (hardness) | Minerals |
a. Soft stone | Talc |
b. | Gypsum |
c. | Minerals |
d. | Flurite |
e. | Apatite |
f. | Feldspar |
g. | Quartz |
h. | Topoz |
i. | Sapphire |
j. Hard stone | Diamond |
Suitability of Stone
Parts of Structure | Stone |
Building Construction | Laterite |
Cement Concrete | Basalt and trap |
Roof Covering, Flooring, Damp proofing, sill, and window | Slate |
Interior decoration of the Building | Serpentine |
Railing Ballast | Granite, Gneiss, Trap |
For fire resistance | Compacted sandstone |
Road metal | Granite and basalt |
Bridge, pier, docks | Granite and Gneiss |
Ornamental work in building | Red and yellow type basalt and trap |
Partitions in Urinals and bathroom | Slate |
Ornamental buildings, Monuments, Statue,s and curved works | Marble |
Flag Stone
This is a rock from the sandstone composed of feldspar and quartz. Sedimentary rock.
Graine Size=0.16-2 m dia.
Use paving slabs, roofing, and memorials.
Properties of Special Stones
Stone | Type | Nature | Color | Uses |
Granite | Igneous | Hard and strongest | Gray, Green, Browness to black | Pier, Bridge, abutment, lighthouse, road pavement |
Salt Trap | Igneous | Hard and Heavy | Gray, bluish, Black | Roda metal, paving, concrete |
Pumice | Igneous 4th | light | Gray, Brownish | Lightweight aggregate |
Sand Stone | Sedimentary | Stratified and soft | white, gray, yellow, Brown | Building element |
Limestone | Sedimentary | Stratified | white, gray, yellow, black | steel manufacturing, paper, and plastic production |
Shale | sedimentary | Laminated soft | greenish gray | tile and brick manufacturing |
Conglomerate | sedimentary | Granular | Light colour, black | building stone |
Gneiss | Metamorphic | Hard | Light color, Black | Paving, Road metal |
Marble | Metamorphic | Stratified | white, black mixed | Ornamental work statue |
Slate | Metamorphic | Laminated hard | Gray, black, blue, purple | Roofing, DPC, Flooring, Bathrooms |
Schist | Metamorphic | Weak | greenish, yellows, brownish black | used for structure |
Moram | Metamorphic | Hard | Dressing of metal road | |
Laterite | Argilleeous | Soft | red, yellow, brown, black | light road, inferior tye building. |
Availability of stone in Nepal
- Slate: Sindupalchoke, Nuwakot, Dhading, Tarhatum, Citawan, Ramechhap and Dolkha.
- Gravel: Lalitpur, Palpa.
- Talc: Sindupalchoke, Makawanpur.
- Sandstone: Kathmandu, Lalitpur, Kaski, Palpa, Dang.
- Marble: Kathmandu, Lalitpur.
- Berril: Taplejung, Sankhuasabha.
- Turmalin: Sankhuwasabha, nuwakot.
- Granite: Sankhuwasabha and Nuwakot.
- Limestone: Kathmandu, Dhankuta, Chitwan, makawanpur and terhatum.
Cement
Cement can be defined as a material with adhesive and cohesive properties which makes it capable of bonding material fragments into a compact whole. cement is one of the best and essential construction materials that help to improve the strength of structure.
It provides a good bond between two materials and provides good strength.
It is obtained by mixing limestone and clay burning them and grinding to fine powder.
Ordinary Portland cement (OPC) is the most popular cement.
The specific gravity of Cement is 3.15.
Water absorption is not more than 5%.
The density of cement is 1440 Kg/m3.
What are the Raw Materials of Cement?
Ingredients | Composition % | Function | Excess |
Lime [cao] | 60-65 | Control strength, Sound, strong | Unsound, expand, and disintegrate |
Silica [Sio2] | 17-25 | Give strength | Slow setting |
Alumina [Al2O3] | 3-8 | Quick Setting | Lowers the strength |
Iron Oxide [fe2O3] | 0.5-6 | Give hardness, strength, and fusion | discolor |
Sulfur trioxide [Sio3] | 1-2 | make sound | Unsound |
Magnesium oxide [Mgo] | 0.5-4 | give color hardness | cracks in mortar and concrete |
Alkalies | 1-8 | Small quantities | Efflorescence |
Composition of Cement Clinker-Bouge’s Compound
Compound | Composition % | Function |
Alite [C3S] | 25-50 | It generates more heat of hydration. Develop early strength and hardness. |
Belite [C2S] | 25-40 | It generates less heat of hydration. Develops unlimited strength. |
Celite [C3A] | 5-11 | It reacts rapidly with Water. It generates more heat of hydration. Help to setting of cement. |
Felite[C4AF] | 8-14 | Less cementing value. React very slowly. Increasing volume of cement. Reduce Cost. |
All the above components undergo some chemical composition during the manufacturing process and from clinker. The constituents of the end product are called Bouge Compound.
A high % of Alite and a Low % of Belite in cement
- Rapid Harding
- High early strength
- The high heat of hydration
- Less Resistance to chemical attack.
A Low % of Alite and a High % of Belite in cement
- Slow Harding
- High ultimate strength
- Less heat of hydration
- Greater Resistance to chemical attack
Note: The sum of % Alite and Belite for Portland Cement is 70-80%.
Types of Cement
I have already discussed the type of cement on my website. But today I will give General information in this post. Perhaps you can learn something from this article. OPC, PPC, and RHPC are the major types of cement available for different applications and different situations.
Ordinary Portland Cement (OPC)
- Common Properties of OPC
- Sufficient resistance shrinkage and cracking less resistance to chemical attack.
- Medium Rate of development strength and heat of hydration.
- Uses
- General construction
- Small Structure
Portland Pozzolana Cement (PPC)
Pozzolana Material 10-25%.
- General Properties
- Gain Strength slower than OPC
- Ultimate strength more than OPC
- Less heat of hydration
- Grater resistance chemical attack
- Uses
- Under construction of water
- Sewage works
- suitable for small concrete works
Rapid Hardening Portland Cement (RHPC)
- General Properties
- Early strength greater than OPC
- Content lime more than OPC
- Heat of hydration Higher than OPC
- C3S more than OPC
- 3 days Strength of RHPC is equal to 7 days’ strength of OPC
- Uses
- Emergency Work
- Road Construction
Note: RHPC is not used for Mass Concrete Construction.
Extra Rapid Hardening cement
Obtain by Mixing CaCl2 with RHC that is used for Road works
Sulfate Resistance Cement [SRC]
- Manufacture by 80-85% granular slag, 10-15% Burnt gypsum and 5% OPC Clinker
- Highly Resistant sulfate attack
- Use in marine work
Low Heated Cement [LHC]
- Properties
- C3S and C3A less and C2S is More
- Strength is gained at a slow rate
- Ultimate strength same as OPC
- Uses
- Mass concrete,
- Dam,
- Retaining Wall,
- Bridge,
- Boutment.
Blast Furnace Cement
- Properties
- Obtain by mixing Portland cement clinker, Gypsum, and Granulated blast furnace slag.
- Uses
- Mass concrete due to low heat of hydration.
Quick Setting Cement
- Properties
- Cement is obtained by adding Al2So4 and Cacl2 with OPC.
- Less amount of Gypsum
- Uses
- Underwater Construction
High Alumina Cement
The amount of Alumina and Calcareous material is high.
Cement can withstand high temperatures.
Cement is used in Refractory concrete.
Resident Cement
Hardening time is 8-10 minutes.
Cement is used in very cold areas and winter season.
Colored Cement
Cement is prepared by china clay and chalk.
The amount of pigment is 5-10%
Cost 2 times of OPC
Used for architectural Purposes.
High Strength Cement
This cement is one of the special types of OPC cement. Compressive strength is higher than OPC.
Hydrophobic Cement
Cement is obtained by mixing OPC clinker with a repellent from a substance like acetic acid, stearic acid, etc.
Masonry Cement
Oil Well Cement
Expansive Cement
Note
- The temperature at the time of Testing is (25-29) degrees Celcius.
- Maximum Pigment percent in the color of cement is 10%.
- The weight of magnesia should not be greater than 5%
Test of Cement
Fineness test
Check proper grinding of Cement and cementing value.
Sedimentary residue of OPC cement should not be greater than 10% of the sample in IS sieve no 90 microns. [1mm=1000 micron]
- Method
- Sieve method
- Air permeability method
Consistency Test
Find the proper amount of water to be added to the cement
Performed by Vicat’s apparatus consists, of a plunger diameter of 10mm and length 40-50mm.
Soundness Test
Find the presence of uncombined lime and magnesia in cement which causes the expansion of cement.
This test is done by LE-Chatelier’s Apparatus.
According to IS Expansion is not exceed 10mm
Setting Timetest
Types of Cement | Initial setting time(min) | Final setting time (min) |
Ordinary Portland Cement | 30 | 600 |
Portland Pozzolana Cement | 30 | 600 |
Rapid Hardening cement | 30 | 600 |
Sulfate resisting cement | 30 | 600 |
Super sulphate cement | 240 | 270 |
Low Heat cement | 60 | 600 |
Blast furnace cement | 30 | 600 |
quick setting cement | 5 | 30 |
high alumina cement | 30 | 600 |
white portland cement | 30 | 600 |
Tensile Strength Test
Tested by Briquette testing machine.
Cement and sand ratio 1:3 (mortar)
Average tensile strength after 3 days of curing is not less than 20 kg/cm2 and after 7 days is not less than 25 kg/cm2.
Compressive Strength Test
Standard cube made of good Portland cement and sand mortar in a ratio of 1:3.
The size of the cube mold is 7.05 cm.
This test is done by a compression testing machine.
Compressive strength after 3 days is not less than 115 kg/cm2 and 7 days is 175 kg/cm2.
Cubes should be kept at a temperature of 27 degrees Celsius.
Note: Three cubes should be tested.
Loss of Ignition Test
Loss of weight of cement 1 gram of sample is heated at standard temperature. Loss of ignition is not more than 4%.
Manufacture of cement
Dry process
Limestone and clay are ground separately into fine powders by a grinding mill and mixed in the desired proportion.
Water (about 12%0 is then added and the resulting product is dried and burnt in kilns.
Clinker obtained after burning is added 3-5% of gypsum and ground to fine powders.
This final product is Cement.
Wet Process
The limestone is ground separately.
Clay materials are mixed with water in wash mills and stored.
Now crushed are mixed with water in wash mills and stored.
Now crushed dry limestone and wet clay are mixed correctly.
Dry Process | Wet process |
Slow and Costly | The quick and easy |
size of the kill needed to manufacture the cement is smaller. | size of the kill needed to manufacture the cement is bigger. |
More economically | Less economically |
The moisture content of these pellets is 12%. | The moisture content of these slurry is 30-50%. |
The amount of heat required is lower. So required lower fuel. | The amount of heat required is higher. So required higher fuel. |
Steps | Steps |
a. Treatment of raw materials | a. Collection of raw materials |
b. burning of dry mix | b. preparation of slurry ( crushing grinding and mixing of raw materials) |
c. Grinding of clinker | c. Buring |
d. Packing and storage | d. Grinding of clinker |
Specific surface
Types of cement | OPC and PSC | PPC | LHPC | RHPC | SRPC |
Surface area (cm2/gm) | 2250 | 3000 | 3200 | 3250 | 4000 |
Flash set
It is the property of concrete by which the upper surface of the concrete becomes hard without setting the inner portion.
This effect is found due to the presence of Tri-calcium aluminate.
Setting and hardening of cement
The chemical reaction between concrete and water is called the hydration of cement. The phenomenon under which the plastic cement changes into a solid mass is known as the setting of cement.
The phenomenon under which the elements paste sets and develops the setting is known as the hardening of the cement.
Strength of cement
After months | 3 | 6 | 12 | 24 |
Strength Reduce | 20% | 30% | 40% | 50% |
Freshness of cement
- The color of cement is uniformly Greenish gray.
- A handful of cement, Through into a bucket of water, floats.
- The hand is trusted into a bag of cement, it feels cool and smooth.
Specification of Storage and transport of cement
Height of cement bag=18 cm
Area of Cement bag= 3000 cm2
Space between piles= 1.6 m
Space from the wall is a minimum of 30 cm
The height of the ground surface is 20 cm.
We are packing weight bag 50 kg per bag.
No bag should not be more than 15 in horizontal and 10 in vertical.
Transport with the help of a truck, lorry, and tractor. it depends on the market.
Admixture
The admixture is the materials other than the basic ingredients of cement concrete added to the concrete mix to improve certain properties—like strength, durability, and workability.
The addition of admixture is done immediately before or during mixing.
Available both power and aqueous solution
The function of admixture
improves workability, strength, and durability.
Increase bond strength between concrete and reinforcement.
improving the waterproofing properties.
Reduce shrinkage during the setting of mortar.
reduce bleeding and segregation effect of concrete.
To produce the color of concrete.
To decrease the weight of concrete.
Types of Admixture
- Accereporor
- Added up to 2% by weight of cement.
- Concrete set and hardened quickly
- Used in Construction in cold climates.
- Reduce ultimate strength and initial setting time of concrete.
- eg, Aluminum fluoride.
- The retarder
- added 2-3% weight of cement.
- Increase the initial setting time and hardening time of the concert.
- For long-distance site locations.
- eg, calcium sulfate, Gypsum, sugar, glucose, cellulose.
- Plasticizer
- Water-reducing admixture
- added to the concrete mix to make more plastic without any further addition of water.
- added below 0.5%
- eg, salt of hydroxyl arty acids.
- Air-entering agent
- resin,
- fatty acids
- oils
- aluminum
- zinc powder
- Bleeding Agent
- paraffin wax
- Colour Agent
- Red Oxide
- Ferrous oxide
- Chromium Oxide
Clay And Clay Product
Now we will discuss clay and clay products. One of the best and most usable clay products is Brick. So many articles published on my website. You have to checkout. Now in this complete construction materials guide main points are covered with clay products.
Brick- No 1 Construction Materials
Bricks are small solid structural units of rectangular shape and convenient size made from suitable types of clay hardened by heat or chemical action. The standard size of brick is 230 x 110 x 55 mm.
Difference Between Stone and Brick
Brick | Stone |
Lighter Than Stone | Heavier than Brick |
Made of Clay | Obtained from rock |
Specific gravity Is 1.8 | Specific gravity Is 2.6 |
Water absorption is less than 15% | Water absorption is less than 5% |
Less durable than stone | High durable than brick |
Uniform color and shape | No-Uniform color and shape |
Absorbe lesser heat | Absorbe higher heat |
The overall cost of manufacture is less | The overall cost of manufacture is high |
Brick Earth
Brick earth is a mixture of clay and sand which when mixed with water becomes plastic and can be easily molded. It is also dried without cracking and warping.
Ingredient of Brick Earth
Ingredients | Composition % | function | Excess |
Silica | 50-60 | main ingredients Reduce shape imparts durability prevent shrinkage and warping | Brittle and weak |
Alumina | 20-30 | Provides plasticity makes brick hard on drying | Crack and warp |
Lime | Less than 10 | Reduce shrinkage | Melt and loose its shape |
Iron oxide | Less than 7 | Give red colour | Dark blue color |
Magnesia | less than 1 | Reduce warping and shrinkage | yellow color, decay |
Alkalies | <10 | For quick setting Help to melt the brick | Efflorescence |
Harmful Ingredients
Ingredients | Causes |
Carbonaceous matter | Brick black |
Iron Pyrite | Split the brick into pieces |
Organic Matter | Brick Porous |
Peebles and gravels | Difficult to mix (non-homogenous brick) |
Sulfur | Brick discolor |
Water | Shrinkage during burning |
Manufacture of Bricks/Preparation of brick earth
Un-Soiling: It is the process of removing of top layer of earth to get the soil tree from pebbles, gravel, and roots.
Digging: It is the process of excavation of soil by adding fly ash, sandy, loam rice husk, etc.
Weathering: It is the process of exposing soil to open weather after mixing a small amount of water to improve plastic and strength.
Blending: It is the process of mixing the appropriate constituents of bricks such as sandy earth, and calcareous earth.
Tampering: It is the proof of leading the soil either by the feet of men or pugmills. The operation of tampering with the pug mill is known as plugging. In tampering with water other substances are mixed to improve the plasticity and durability of bricks.
Molding: It is the process of making the bricks of required shape and size from tampered or plugged clay. Molding is done by either hand or machine.
Drying: It is the process of removing the moisture to control shrinkage and save fuel and time during drying. Drying is natural and artificial.
Buring: Three-stage
- Dehydration (400-650) degree Celcius
- Oxidation (650-1000) degrees Celcius
- Vitrification (900-1100) degrees Celcius
Classification of Bricks
There are many classes of brick available in the market but three are main. 1st, 2nd and 3rd class brick. I have classified three major classification based:
Based on field practices
First-class Brick
- No 1 construction materials
- They are well brunt and regular shape and size.
- Have uniform texture and color ( deep red cour)
- Sufficiently hard and sound
- Minimum crushing strength is 15 kg/cm2 {10.5 N/mm2}
- Specific Gravity is 1.8.
- Metalic sound
- Water absorption capacity is not more than 15% {24 hr}
- Not Break, dropped from height 1-2 m
- Size of brick [ NS=230 x 110 x 55]
- Used in masonry, Flooring, facing works
Second Class Bricks
- They are well brunt but irregular in shape and size.
- Does not have uniform texture and colour.
- Not so hard
- Ringing Sound
- Minimum Crushing strength is 70 kg/cm2 [7N/mm2]
- Water absorption capacity is less than 20%.
- Used in interior wall construction.
Third Class brick
- They are burnt and irregular in shape and size
- Does not have a uniform texture and yellowish colour.
- Soft
- Dull sound
- Minimum Crushing Strength = 35-70 kg/cm2 [3.5 -7 N/mm2]
- Water absorption capacity =<25%.
- Used in inferior and temporary structures.
Overburnt or Jhama Brick
- They are overburnt and irregular in shape and size
- Dark in color
- Brittle in nature
- Product metallic ringing sound
- Hard and strong
- Crushing strength = >15 N/mm2
- Used in aggregate for concrete, road metal, and filling materials.
On the Base of Use
Common Brick: Used for filing, and backing.
Facing Brick: Used in front of the building wall, good appearance.
Engineering Brick: Strong, Impermeable, Smooth, and Hard.
Based on Finish
- Sand Face Brick
- Rustic Brick
Based on Manufacture
- Hand made
- machine made
Based on Buring
Pale Brick | Body Brick | Arch brick |
Unbrunt | Well Burnt | Over Burnt |
Some other types of bricks
Fire Bricks/ Refractory Bricks
- It is made of fire clay of high temperature in a special kiln.
- Crushing strength=125 kg/cm2
- Water absorption =5-10%
- used combustion chamber
- Chromic Natural refractory brick
- Dolomite and Bauxite basic refractory brick
- Unit weight= 2400 kg/m3
Hollow Bricks
- Volume not less than half of gross volume
- Used non-load-bearing wall and Ornamental works
Testing of Brick
Compressive Strength Test
- Minimum no of specimen=5
- Specimen brick is immersed us water for 24 hr.
- Forg of brick is filled with 1:3 cement mortar and stared in damp jute bags for 24 hrs.
- Immersed in water for 3 days
- Specimen placed on compression testing machine.
- Load is applied at a uniform rate of 14 N/mm2 per minute.
- Maximum load is recorded.
Compressive strength=Maximum load at failure/Loaded are of Brick
Water Absorption Test
- 3-5 samples of brick are taken
- It is done at a temperature of 27 degrees Celcius.
- The specimen brick is first weighted dry W1
- Then immersed in water for 24 hrs
- It is weighted again W2
Water absorption={(W2-W1)÷W1}*100
Efflorensces Test
Measure white patches
Efflorescence | Nil | Slight | Moderate | Heavey | Serious |
Deposit | Not Found | <10% | 10-50% | >50% | Exposed area |
Warping Test
Check the bend and twist of the brick.
Dimension Test
Nepal Standard | 230 mm x 110 mm x 55 mm |
Indian Standard | 19 cm x 9 cm x 4 cm |
No Brick is Required for 1 m3
- Hand made 530-560 ( as wastage %)
- Machine made 530-500 ( as wastage %)
Defect of Brick
- Buring brick absorbs water reducing the strength
- Over-burning brick products soften the mass loose shape
- Chuff hot brick with cool water formed cracks and deformation
- Black core
- Crack or checks– excess of water and lumps of lime.
- Efflorescence– white and gray salt is deposited in brick due to the alkalies present in the soil.
- Bloating– Brick swelled due to carbonaceous matter and sulfur
- Lamination– Reduce weak strength due to Entrapped air in brick.
- Spots– Dark sulfur spots due to iron sulfides.
Other Important Terms
Terracotta
- It is a type of fired clay or earthenware made by mixing clay with water shipping.
- Burnt in special klin (Muffie Furnace)
- Temperature= 1100-1200° C
- Used=Pottery, decorated objects, building materials (roof tile, Bricks).
Surkhi
- Form of powdered Brick
- Made by finely grinding burnt clay bricks
- Mixed with cement to create Mortar
- Substitute for sand
- Improve strength and durability of concrete and mortar reduce shrinkage and cracking.
Fly ash
- Fine powdery substance
- Produce during the combustion of coal
- Used as a partial replacement for cement in concrete.
- Improve strength and durability.
- Used Production of Brick
Porcelain
- Type of ceramic material
- made by the heating material, typically including clay in combination with other minerals at high temperatures.
- Properties: white, Hard, translucent, and glazed surface.
- Used: Dinnerware, Voses, figurines, and decorative.
Bricks Bond
→ pattern in which bricks are laid to form a wall or other Structure.
Types of Bond | Explanation |
Stretcher Bond | → Bricks are laid as stretchers on the face of the Wall. → Used For single brick walls or half brick Walls. → Also used for cavity wall as less cutting required |
Header Bond | → Bricks are laid as Header on the face of the Wall. → Used for one brick Wall |
English Bord | → Bricks are laid by alternate course of heoders & Stretchers. → Strongest bond and Carry heavy load → commonly used for all wall thicknesses, |
Flemish Bond | → Bricks are laid by each course alternate headers & Stretchers → More decorative. |
Frog
→ Depression on the top of the brick.
→ Works as a key at the time of laying of bricks.
→ sizer 10cmx 4cm x (10-20) mm Used Advertisement of manufacture & reduce Weight.
Brick Nogging
→Construction techniques
→ Bricks are filled in a Wooden frame.
→Provide additional Strength & Stability to the building Wall or ceiling.
Quality of Good Brick
Shape & size → Uniform in size, uniform surface with well-defined edges.
Color → Copper Colour.
Structure → Fine Compact & uniform structure.
Hardness → Sufficienhy hard and hot be scratched by a fingernail.
Porosity → not absorb too much water,
Strength → sufficiently strong & hot Crack under loading.
Durability → Not damaged by the environment.
Resistance to Fire
Resistance to effiorescence
Note: Compressive strength
- Hand-made brick = 30-150 kg/cm2
- Machine made brick = 450 kg/cm2
→ Normally, Height of Chimney = 30m
→ Glazing is used to make earthenware impervious.
→ Damper → metal plate → Used close or open Chimney of kiln.
→Purpose Regulate the flow of air in the kiln during the firing process.
→ Internal size of mold take Slightly. (about 1th/10) greater the brunt brick
→ The height of the wall Can be raised in one day,
- Stone masonry = 60Cm•
- Brick masonry = 100cm.
→weigt of one brick = 2-3 kg
→ Volume of one brick = 1680 cm3
Paints & Varnishes
paints and Varnishes are used to protect metals, and timber of plastered Surfaces from the corrosive effects of weather, heat, moisture, or gases. They are also used to improve their appearance.
Paint
It is the fluid paste prepared by a mixture of the base with Vehicle, pigments, thinner, drier, adulterants, extender, etc
Uses/Function of paint
- Decoration purpose
- Conservation purpose
- Hygienic purpose
- Prevents corrosion.
Ingredients of paints
Ingredients | Functions |
Base | → Body of paint. → Also called oxides of metal. → It gives a thin layer (film) That protects from weathering effect. → It has binding properties. → Example Used on Wooden surface – White lead, Zine White. Used on Metal surface – Red lead, Iron oxide. → Aluminium powder etc. |
Vehicle | → Also called Carrier, liquid, drying oil. → It binds based pigments together: → It spreads the base over the surface. →Examples Linseed oil (most used), Fish oil, Tung oil, Nut oil, Poppy oil, etc. |
Pigments | →Gives Colour to the paint. →<10% → White color -White lead, zine oxide → Red color- Red lead, Rion oxide, Carmine, Vermillion →Blue color- Indigo, cobalt oxide. →Brown color- copper oxide, raw & burnt umber → Green Colour – Chromium oxide, copper sulfate → Black Colour – Lamp black, vegetable, and ivory black. → Yello Colour – Hello chrome, ochre, taw Siena |
Drier | → It helps to dry the Vehicle. →<8% → Example Letharge (mostly used), Zine sulfate, Lead acetate, Red lead, Magnesium. |
Thinner (Solvent) | → Also Called Volatile substance → Make its application easy, smooth, and thin. → Examples Turpentine (mostly used), Peltoleum, Kerosene, Sprit, Naptha, Water etc. |
Adulterants (inert filler) | → Increase Weight and durability. → Reduce Cost → Examples – Aluminium, Silicate, magnesium silicate, calcium Carbonate, Barium Sulphate, |
Extender | → Increase Volume Examples Silica, talc, gypsum |
Note: more poisonous – Lead paint
Types of paint
Types of paint | Uses |
Aluminum paint | → Resist High temperature → Uses – oil and gas, Storage tank, hot water pipes, electrical, teléphone poles, silos, metal roof, etc. |
Asbestos Paint | →Fire resistance → prevents leakages, →Uses -metal roof, gutter, and the outer surface of the basement wall. |
Bronze Paint | → High refrective used: radiator of vehicles. |
Enamel paint | → Used Timber, concrete, metal, etc. |
Cenurose paint | → Used in expensive materials. → Ducco paint |
Oil paint | → Used airplanes, ships, car eteriliboso → Ordinary paint, easily available, cheaper → used Automobiles. |
Emulsion pant | → Used concrete surface in a wet area. |
Fluorescent paint | → It has shinning property. → visible at Night |
Cement paint | → Based on white cement Thinner Water →Used concrete face, plastered surface |
Plastic paint | → Dense in Nature → Give very attractive Looks Used in Auditoriums, Showrooms, offices, etc. |
Bitumen paint | → It gives a highly protective layer → Used Underwater pipes |
Casein paint | → Used plastered surfaces, Walls, and Ceiling, etc. |
Zine paint | →Used Illumination of maps |
Preparation of paints
First of all, the base is finely ground with the help of a muller. Then mixed with the Vehicle. It gives a thick paste.
Then, this thick paste is mixed with thinner. It gives a Consistent/thin paste.
NOW, separately ground pigment & driers.
Then, all the above three pastes are mixed and give a paint.
Defects in paint
Blisterings: Swelling of paint
Chalking: Conservation of Paint in Power Form.
Checking → Formation of cracks on the surface of the paint.
- crazing → cracks produced in a small area
- Crocodiling → Cracks produced in Large areas.
Cracking: Cracks developed throughout the thickness of paint.
Alligatoring: One layer of paint slides over the other due to the Hard paint being applied over a soft one or Vice Versa.
Flaking: Detachment of paint film from the surface due.
Discoloration: Alteration in the original Color.
Varnish
It is a homogenous mixture of natural or synthetic resin with solvent & drier.
→Varnish dries off & leaves a transparent or semi-transparent Fim of resin.
→ It does not contain pigments.
The function of varnish
- Protect the painted surface
- Gives a shinning effect to the painted surface.
- Gives brilliance to the wooden surface, photograph, map, etc.
Ingredient of varnish
Resin → Principle Constituent → Examples: Copal, amber, gum, mastic
Solvent → Examples Linseed oil, turpentine oil, methylated spirit, or alcohol.
Driet → Examples Lead acetate, White Copper, lethargy.
Types of Varnish
Types of Varnish | Explanation |
Dir Varnish | → Resin + Linseed oil + Turpentine + drier → Dries DiP Very Slow. → Most durable. → Used Exterior & Interior surface. |
Spirit Varnish | → Resin + Methylated spirit → Brilliant appearance Dries of very quickly. → Less durable → Used/ Interior surface. → Eg French polish, lacquer |
Flat Varnish | Give dull appearance. Used Timber for protection. |
Spar Varnish | → Sticky, in nature as temperature, rise →Used spars, Exterior part of ship, boat |
Water Varnish | → Hot water + ammonium etc. → used photograph, map. |
Turpentine Varnish | → Dries off quickly → Less durable than Oil Varnish → Used Metal painted surface → Not so tough |
Asphalt Varnish | → Fabricated steel Works. |
Distempers
→ Also Called Water paint
→ Obtained Mixing. White Chalk and Water. Base Chalk Thinner Water Main principle constituents chalk. Removed by water
→ Less durable Use Temporary and Interior surfaces.
→ Not exposed to the atmosphere,
→ For color used to pigments
Bitumen
It is a binding material in a solid or semi-solid State.
Properties of Bitumen
Colour Black State semi- solid Sp•gravity 1.09 soluble in Carbon disulfide, Carbon tetra chloride, Chlorofurm, benzene
→ Non-Crystalline Solid
→ Viscous material
→ gets softened as the temperature rises.
→ Catch fire at 200°c
→ Ductile in Nature.
→ Chemical Compound Carbon & Hydrogen derived from petroleum crude oil
→ Bitumen is hot and affected by air, light, or water individually but in Combination, they can make brittle and porous.
Uses of Bitumen
→ Road pavement
→ paint formation
→ crack repairs
→ Heat insulation purpose
→ DPC, leakage prevention
→ Batteries
→ Root sealing
→ Joint fitter etc.
Classification of Bitumen
- General Classification
- Cutback Bitumen
- Obtained by Bitumen+ solvent (kerosene, petroleum, naphtha, gasoline, etc)
- The solvent turns the bitumen from a semi-solid to a liquid state.
- No heat is needed before using it.
- Used
- Road pavement in cold areas,
- Manufacturing of paint,
- Soil Stabilization
- Bitumen Emulsion
- Obtained by Bitumen + water + Emulsifier
- It is an aqueous solution
- Used
- Road pavement,
- Soil stabilization.
- Blown or oxidized Bitumen
- Obtained by passing air at high temperature & pressure.
- Function Heat insulation used flooring, Roofing, Joint, etc.
- Plastic Bitumen
- Obtained by Bitumen + Iner Firer (40-45%)
- Inert firer Asbestos powder.
- Used Crack repairs
- Rut or Straight run Bitumen
- It is obtained after distilling a Crude oil having required penetration, and viscosity.
- They were used without further treatment.
- Based on source
- Natural Bitumen
- Petroleum Bitumen.
- Based on consistency (at 18°c)
- Solid Bitumen
- Semi – Solid Bitumen
- Liquid Bitumen
Based on Application (Uses)
- Road ConStruction Bitumen
- Building Bitumen
- Roofing Bitumen
Test of Bitumen
Types of Test | Explanation |
Penetration Test | Equipment: Penetrometer Measure: Softness and hardness of bitumen Needle allowed penetrates Time: 5sec. Standard Temperature: 25 sec |
Softening Point Test | Equipment: Ball and Ring Measure: Softening point The temperature increase rate is 5 degrees c. Measure the Temperature from the ball drop from the ring. Good bitumen softening point =35° C-70° C. |
Ductile Test | Equipment: Standard Briqutte testing machine Measure: Elongation before failure Pulling Rate: 50mm/min Ductile Value: 50cm (good bitumen) |
Specific Gravity | Instrument: Pycnometer Measure: Specific gravity Sp= 1.09 |
Viscosity | Instrument: Orifice Viscometer Measure: Resistance to flow Measure in terms of time sec size of orifice= 4mm, 10mm |
Flash and Fire point test | Equipment: Pensky martens tester measure: flash and fire point General value: 200° C |
Loss of Ignition test | Equipment: Hot air Oven |
Solubility test | Soluble in carbon disulfide, carbon tetra chloride, etc. Measure: Purity of bitumen. 99% soluble for good bitumen. |
Water absorption | >0.2% |
Tile
Tile is a manufactured piece of fired clay, Stone, or concrete, Used to cover Walls, floors, roofs & ornamental or architectural purposes. This is one of the best and most popular construction materials in the world. In modern technology, most of the people are used tile in the construction. Most of the tiles are manufactured in Square and Rectangular shapes.
Types of Tiles
- Based on Location
- Wall Tiles are laid on the wall used Both inside and outside of the building.
- In the Inside Bathroom, the Kitchen Wall outside is Used for cladding.
- Floor Tiles
- Laid on Floor
- Roof Tiles Laid on the Roof of a single-story house.
- Paver tiles
- Laid in covering the parking area, driveway, and surrounding area of a building.
- Based on materials & Manufacturing process
- Ceramic Tiles
- Ingredients clay, silt, sand of traces other
- Commonly used Residential building in interior walls & Floors.
Types of Ceramic Tiles
Glazed Ceramic Tiles | Unglazed Ceramic Tiles |
→ Liquid glass coating over the Top of tiles, | → No coating |
→ Appearance Infinite color, finishes, texture | → Appearance Natural earthly |
→ Water proof | → No waterproof |
→ Density Less | → Density High |
→ Waterproof | → Thickness Thicker |
→ Durability | → Durability |
→ Low Slip | →More slip |
→ Cost Expensive | → Cost Cheaper |
Porcelain tiles
Similar to ceramic tiles Clay grain more finer and Fired at a higher temperature than ceramic tiles, it is also, Denser, Less porous, durable, and resistant to moisture the ceramic tiles. used Both residential And Commercial buildings.
Mosaic Tiles
Made of Ceramic, glass, stone, or metal. Decorative pieces used in the Bathroom, kitchen, swimming, pool, etc.
Clay Tiles
Made by pressing. & buthing Clay. used low-cost housing, the roof of the building.
Testing of Tile
Test | Explanation |
General Quality Test | → Well but not → Shape and Colour uniform or not → Cracks are present or not |
Warping test | → 2% in sides → 5% in diagonal |
Hater absorption test | → less than or equal to 24% |
Dimension test | → Requred dimension or not |
Aggregates
Aggregates are inert materials mixed with a binding material (cement, lime) in the preparation of mortar or concrete.
Types of Aggregates
Based On Size
Fine Aggregates | Coarse Aggregates |
→ Small size filer material in construction | → Large size filer material in construction |
→ pass 4.75 mm sieve | → Pass 75mm Sieve |
→ Retain 0.075 mm sieve | → Retain 4.75 mm Sieve |
→ example: Sand, Stone Screening surkhi, fly ash, etc. | → example: Gravers, Pebbles, brick & stone chips, clinkers, etc. |
Voids between the Coarse aggregate are filled up. | Acts as inert filler material For Concrete |
Based On Shape
Types of Aggregates | Explanation |
Rounded Aggregates | → Voids 32-33% → Good workability. → Strength More Bond Strength Less. → Not suitable for strong concrete |
Itegular Aggregates | → Void generate 35-38% → Less Workability → Water and cement are more required for the Constant W/C Ratio → Bond strength More than Rounded aggregates → Not suitable for strong concrete |
Angular Aggregates | → Voids/ 38-40% → Less Workability then Rounded aggregate → Bond Strength More → Suitable High strength Concrete. |
Based on moisture Content
Types of Aggregate | Pores | Surface |
Very dry aggregate | No moisture | No moisture |
Dry aggregate | Some moisture | No moisture |
Saturated surface dry aggregate | Filled with water | Dry |
Moist aggregate | Filled with water | Wet |
Note: Size of Aggregate for concrete=20 mm, mass concrete=40mm or more, and flooring=10mm.
Quality of good Aggregate
Strength → sufficient strength to resist stress
Durability → Resistance to Weatheting, environmental factor
Shape and size → Uniform, compacted, interlocked effectively:
Water absorption → < 10 %.
Cleanliness → Free from organic matter; Clay etc.
Test of Aggregate | Explanation |
Impact Test | Apparatus: Impact Testing Machine Find: Toughness |
Crushing Test | Instrument: Los Angles Amchine |
Abrasion Test | Find: Durability |
Water Absoption Test | <10% |
Bitumen Adhesion Test | Find: Striping Value |
Shape Test | Determine by % of Flanky and elongated particles contained in it & by its Angularity |
Timber
Timber is a wood that is used for construction purposes.
→ Freshly felled timber Consists of 100% moisture of dry Weight and 50% moisture of total weight. (Amount of moisture = Amount of timber)
Seasoning: The process of reduction of moisture from timber.
Method of seasoning
Natural Method
→ Water Air dried is done.
→ Time Consuming (6-8 month)
→ Less efficient (Reduce moisture up to 12-15 %)
→Economical
Artificial Method
→ controlled heat and humidity are used to reduce the moisture Content.
→ Fast
→ Reduce moisture up to 90%
Purpose of Seasoning
→ Make fire resistance
→ Waterproof
→ make light, Strong, and stable.
→ prevents warping, cracking, shrinkage.
→ resistant to decay by fungi, termites
→ resistance to electricity.
Classification of Timber
Based on the Growth Mode
Endogenous:-Growth endward
→ Example, Bamboo, Coconut, palm, hanut.
Exogenous:- Growth outward → Examptel sai, teak, deodar, Shisham
Types of Exogenous
Conifers | → pointed leaves Example Deodar, chit |
Deciduous | Flat Leaves Example take shisham |
Based oh Hardness
Hard Lood – Sal, teak, shisham, oak etc.
Softwood – deodar, walnut, kail, chai, etc
Internal Structure of Wood
Pith: Inner-most part or core of the tree. Also caned Meduna
Heart Wood: Innermost annuat ring. Also Called Duramen Responsible for strength, hardness color Darker.
Sap Wood: Living part of the timber. Color Light → outermost annual ring → active & younger part. Function Transmits the Sap from roots to branches.
Bark: Outermost skin of the tree. Function protects an inner portion of the tree from external injuries. Inner bark → Live bork → Outer bark→ dead bark → Inner bark covering cambium layer.
Cambium layer: a layer of Woad between bark & sap Hood. → If the cambium layer is exposed to the atmosphere, the tree dies.
Annual Ring: Ring Formed in timber. Determine the Age of the tree. → {Total no of annual ring = Age of tree}
Medullary rays → They extend radially from the pith to the cambium layer.
Function Binds all annual rings. → Carries nutrients outward.
Defects of Timber
Foxiness: Timber turning into yellowish pried around the pith.
Knots → Root of the branch → Annual ring perpendicular to stem.
Rind galls → swellere part of timber, due to improper cutting.
Bird eye → Small, Circular areas on Wood surface caused by indented Wined fibers.
Burl → Uneven projection on the body of the tree during its growth.
Reason sock of injury at its young age Due to hardening.
Druxiness → Top surface of timber indicates White spots. Reason Access of fungi.
Upsets → Fibers injured by Crushing of compression.
Rupture → Caused due to injury of impact.
Twisted Fibers → Caused by wind constantly turning the trunk of a Young tree in one direction.
Checks of Shakes → Lengthwise Separation of Llood is known While perpendicular to length is called sakes.
Wood Warping → Deviation from flatness Reason Uneven drying results from stress.
Preservation of Timber
Charraing: Burining of timber surface to protect from white ants and fungi.
Terring: Applying a coat of tar for a door frame.
Painting: Oil Paints are suitable to prevent form moisture.
Creosoting: Prepared by Distillation of tar. This color is dark brown.
Walman salt: Contains 25% sodium fluoride, 25 % disodium, Hydrogen arsenate, 37.5% sodium chromate.
Fire resistance of timber: The fire resistance of timber can be enhanced either by impregnating it with chemicals like phosphate of ammonia, ammonium chloride, a mixture of ammonium phosphate of ammonium sulfate, borax & boric acid, sodium arsenate, sodium tetra-borate or by designing wood to provide a slow-burning constituent.
PLY Wood
It is a combination of veneers. → Veneers are placed to each other by gluing. Veneers Thin sheet of wind sliced from log → Thickness = 0.4-6mm.
Some Key points of plywood
→ Density of timber = 1/12th of steel.
→ strength of timber = 1/10th of steel.
→ The strength of timber increases with an increase in the Medullary ring.
→ Timber is an organic material with having cellular structure
→ Defect due to imperfect seasoning = honey, Combing
→ Moisture Content of timber formwork= > 15%
→ Used Timber formwork →4-5 times Steel formwork→ upto 50 time
→ Good timber Sound = sonorous → Used for railway, Slipper = Sal, kail.
→ Board Thickness = <5Cm & Width = exceed 12cm
→ Strip Thickness = 5cm < Width = 10cm
→ Thickness of five play Sheet = 6-9mm
→ Thickness of lamin board = 12-25 mm •
Sawing Method
Ordinary Method /Flat Method
Tangential Method→ Less wastage. → Most economical.
Radial Method→ Maximum strength →’ Maximum Wastages.
Quarter Method
Metals & Alloys
Metal Metal is a solid material That is typically hard, shiny, malleable, and ductile with a good conductor of heat & electricity.
Types of Metals
Ferrous Metals: The main Constituent, for Example, Iron, Steel is Widely used in Different engineering structures such as building frames, beams, columns, roofs, bridges, etc.
Non-ferrous Metal: The main constituent is Not iron. → They are hot magnetic, for Example Aluminium, copper, Lead, Zine, Tin, etc
Ore: Ore is a type of material used to extract metals.
Name of Ore | Iron Content | Chemical Formula |
Magnetite | 70-75% | Fe3O4 |
Hematite | 70% | Fe2O3 |
Limonite | 60% | 2Fe2O3.3H2O |
Iron Pyrite | 47% | FeS2 |
Siderite | 40% | FeCO3 |
Types of Iron
Pig Iron
→ First and basic form → Manufactured in a blast furnace.
- Lowest quality
- Remove impurities
- Crude & impure iron.
- Carbon content = 3-4
Types of pig iron
Bessemer Pig is obtained from Hematite ore Free from sulfur, Phosphorus, and Copper. It is used to make Mild Steel.
Foundry |Gray pig Obtained from Furnace → sufficient fuel high-temperature → Used for making Cast iron.
Forge/white pig→ obtained from Furance → sufficient fuel at low temperature → Used for making Wrought iron.
Molted pig → property between foundry & Frog pig. Used for heavy Casting equipment.
Cast Iron
→ Obtained by melting pig iron Obtained from cupola furnace
→ Carbon Content = 3%
→ More pure than pig iron.
→ Hard & brittle.
→ Used Structural work & Cast iron pipes.
Wrought Iron
→ purest form of iron.
→ Carbon Content = 0.15%-
→ Soft & easily welded.
→ produced by Removing impurities of cast iron.
used plates, rivets, sheets, pipe tubes, railing, window guards, etc.
Steel
→ Most suitable building material
→ Unit weight of steel = 7850 kg/m2
→ Coefficient of thermal expansion = 11.5×10-6 per°c.
→ Intermediate form between cast iron & wrought iron.
Classification of steel
Types of Steel | Dead MS | Mild | Medium Carbon | High Carbon | Tool Steel |
Carbon Content | <0.15 | 0.15-0.3 | 0.3-0.8 | 0.8-1.5 | >1 |
Mild Steel
→ Low carbon, ductile, malleable & more elastic than wrought iron.
→ Ultimate comp. strength = 800-1200 N/mm?
→ Tensile strength = 600-800 Nimm’.
→ Rust quickly.
→ Can be permanently magnetized Uses construction work. huts, bolts, plates, reinforcement bars, toot covering, etc-
→ Sp. gravity = 78 → Tough → soft → Easily Froged
Medium carbon steel
→ stronger & harder than mild Steel.
→ Less ductile, tough, malleable.
Used metal ropes, wires, garden toots, automobile components,
High carbon steel
→ Hardest
→ Less ductile, tough, and Malleable
→ Better resistance to wear & tear, shocks, and vibrations. → More difficult forge & weld.
→ Ultimate comp, strength = 1350.Nmm2
→ Tensile Strength= 1400 – 2000N|mm2.
Used To make Chisels, hammers, drills, files, lathe tools, hacksaws, blades-
Alloys
An alloy is a combination of metals or other substances.
Name of Alloy | Elements | % |
1. Brass | Copper+ zinc | 60+40 |
2. Bronze | Copper + Tin | 90+10 |
3. Invar | Steel+Nikel | 64+36 |
4.Monel Metal | Copper + Nickel | 60+40 |
5. Stainless steel | Chromium + Nickel | 18+8 |
6. Solder | Lead+Tin | 1:2 |
7. German Silver | Copper+ zinc + Nickel. | 50:19:31 |
8. Brazing | copper+ Zine+ Tin | 4:3:2 |
Note: →% of cobalt in, Carbon steel to make magnet = 45%
→ Vanadium steel is generally used for axle f springs.
→ Yield & tensile strength of low-carbon steel may be improved by the addition of vanadium.
→ Malleability Different shapes by heating.
→ Ductility Transferred into wire.
→ Minimum 40% of iron is available in blackbond.
→ Red short iron Cracks When bent due to the presence of sulfur.
→ Brittleness of cold is due to excessive phosphorous.
Lime
Lime is calcium oxide (cao). It is hot and found in nature in a free state. It is obtained by burning limestone at 800°c. or Calcination of limestone with Chalk, Kankat & other Calcareous Substance.
Cementing material → It is easy to work
→ provides strength to the masonry.
Used → plastering, the interior surface of the Wall, preparing, concrete Pot foundation, flooring of ordinary, building, washing the rooms, Stabilizing the soil & knotting of timber Wotks before painting.
Note: In Lime manufacturing fuel hot direct contact. With lime= flare kiln & direct contact = flame kiln sand mixed with time mortar to prevent shrinkage & Cracking •
Types of Lime
Based on source
Stone Lime: From Limestone (Uses Mortar, flooring
Kanker Lime: From Kankar. Uses Mortar (substructure)
Shell Lime: From Shels of sea animals. Uses Lime pinning, White blush & color wash.
Based on purity
Fat, rich, pure, high calcium & white time
→ Impurity >5% → Volume – 2-3 times after slaking.
→ Uses plaster, whitewashing, etc. A color milky White.
→ Sound produce Hissing
→ Contains 95%. Limestone 5% and other materials.
→ Soluble in water.
→ setting & hardening actions are Slow.
→ Slaking Complete = 3-4 hrs
Hydraulic Lime water Lime
→ Impurity 5-30%
→ Volume 2-3 times after slaking.
→ Uses for making mortar for heavy masonry works, lime concrete, Work under water & foundation.
→ Colour Grayish khite.
→ Sound produced Not hissing
→ Slaking Complete 24-48 hrs. Obtained by Burning Kankar.
Initial setting time = 120 min.
→ Contain 30 % of clay.
Types of Hydraulic Lime
Feebly Hydraulic Lime:
- Silica & alumina < 10%,
- Staking time = 5-15 min
- Setting time = 21 days.
Moderately Hydraulic Lime:
- Silica & alumina = 10-20%
- slaking time = 1-2 hrs
- Setting time = 7 days.
Eminently Hydraulic Lime:
- Silica + alumina= 20 – 30%
- Slaking time = 2-5 hrs
- Setting time = 2-48 hrs.
Poor or Lean Lime.
- Impurity > 30%
- Uses poor mortar & plaster
- Also carried Meager lime
- Colour Muddy White
- Contain >30% of clay
- Slaking Very Slowly
- Hardens Very Slowly
- Not set underwater
Based on purpose
Class A (Eminently hydraulic lime)
- Cao 60-70%.
- Clay 20-30%
- Setting time = 2-48 hrs.
- Use: Mortar & Concrete.
Class B (semi-hydraulic lime)
- Cao 70%
- Clay 15%
- Setting time= 7 days
- Uses: mortar, Flooring & concrete.
Class C (fat lime)
- Cao 93%
- Clay 5%
- Volume = 2-3 times after slaking.
- Uses plaster & Whitewashing.
Class D (magnesium lime)
- CaO and Mgo 85%.
- Uses plaster & White Lashin
Class E (Kankar Lime)
- Cao 20% → Mgo 5%
- Uses: mortar, plaster & Whitewashing
Note: Normal curing period for lime mortar = 7 days.
Terminology
Coarse stuff → material of rough or uneven texture.
Hydrated lime → dry powder → Obtained by Treatment of quick lime with Water → Also called Slaked Lime:
Quick lime → obtained by calcination of pure limestone.
Mik lime → Thin pourable solution of staked Lime with water:
Lump lime → quick lime as it comes from a kiln.
Calcination → process of heating limestone in contact with air;
Slaking → process of adding water to quick lime to form calcium hydroxide.
Lime putty → obtained by Slaking or mixing quicklime with water.
Test on Lime
Visual inspection → Examined for its. Color & lumps.
Hydraulic acid test, → Find the carbonate Content of lime. Soundness test,
→ Find the quantity of lime.
Workability, test → know the workmanship.
Balt test → Find expansion of disintegration of bail of lime.
Impurity test→ < 10% Good → 10-20% Fair → >20% poor
That is all for today. All the discussed are construction materials used in the construction. Maybe you will find all the information on construction-related materials. I hope you can select the best materials for the construction according to their type, uses, quality test, and technical terms. Thanks for visiting us.