Table of Contents
Building Material- Crushing strength of good stone
MCQ about Crushing strength of good stone
The crushing strength (MPa) of good stone used for construction of a building must not be less than
- 10
- 50
- 100
- 120
A good building stone has the following properties:
Percentage of wear in the attrition test should not be more than 3
Specific gravity should be at least 2.7
Coefficient of hardness should be greater than 17
Percentage of water absorption by weight of stone should be less than 5
Toughness index should not be less than 13
Crushing strength should be greater than 100 N/mm2
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Building Material - self compacted concrete
Self Compacted Concrete MCQ
For self-compacted concrete water/powder ratio by volume should be
- 0.80 to 1.0
- 1.2 to 1.4
- 0.6 to 0.8
- 1.0 to 1.2
Indicative proportions of materials are shown below for self-compactible concrete:
1) Water/powder ratio by volume is to be 0.80 to 1.00
2) Total powder content to be 160 to 240 litres (400-600 kg) per m3
3) The sand content may be more than 38% of the mortar volume.
4) Coarse aggregate content should normally be 28 to 35% volume of the mix.
5) Water/cement ratio is selected based on the strength required. In any case, water content should not exceed 200 litres/m3.
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Building Material - Hydration of Portland Cement
Hydration of Portland Cement
CORRECT decreasing order of rate of hydration of Portland cement compounds
- C3A
- C4AF
- C3 S
- C2 S
The setting and hardening of cement after addition of water is due to hydration of some of the constituent compounds of cement such as Tricalcium aluminate, Tricalcium silicate, Dicalcium silicate, and Tetra calcium aluminoferrite.
These compounds are known as Bogue’s Compounds.
Hydration of Bogues Compounds
Tricalcium aluminate (C3A):
Celite is the quickest one to react when the water is added to the cement. It is responsible for the flash setting. The increase of this content will help in the manufacture of Quick Setting Cement. The heat of hydration is 865 J/Cal.
Tricalcium silicate (C3S):
This is also called as Alite. This is also responsible for the early strength of the concrete. The cement that has more C3S content is good for cold weather concreting. The heat of hydration is 500 J/Cal.
Dicalcium Silicate (C2S):
This compound will undergo reaction slowly. It is responsible for the progressive strength of concrete. This is also called as Belite. The heat of hydration is 260 J/Cal.
Tetra calcium Alumino ferrite (C4AF):
This is called as Felite. The heat of hydration is 420 J/Cal. It has the poorest cementing value but it responsible for long-term gain of strength of the cement.
For the rate of hydration is highest for C4AF and heat of hydration is highest for C3A.
From the above, the decreasing order of rate of hydration of Portland cement compounds is
C4 AF > C3 A > C3 S > C2 S.
For the heat of hydration, decreasing order of heat of hydration of portland cement is
C3 A > C3 S > C4 AF > C2S
Note: Heat of Hydration and Rate of Hydration is different
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Building Material - Bricks question
MCQ about Bricks
Which of the following is the main reason to provide frog in the bricks?
- Print manufacturer’s name.
- Form keyed joint between brick and mortar.
- Improve thermal insulation
- Reduce the weight of brick.
Frog: It is an indentation or depression on the face of a brick made with the object forming a key for the mortar. This prevents displacement of the brick above.
∴ The term frog means a depression on a face of bricks.
Some other definitions:
1. Quoins is the exterior angle of a wall.
2. Closer is the portion of brick cut in such a manner that its one long face remains un-cut.
3. Bat is the portion of brick cut across width.
4. Perpend is that vertical joint on the face of wall, which lies directly above the vertical joints in alternative course.
5. Stretcher: Bricks are laid along its length.
6. Header: Bricks are laid perpendicular to the face of wall.
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Advantages of Seasoning of timber - Building Material
Seasoning of Timer MCQ
following statements are true or false:
Seasoning of timber results in:- 1 Increased strength
- 2. Increased durability
- 3. Reduced resilience
Three most important advantages of seasoning have already been made apparent:
1. Seasoned timber lasts much longer than unseasoned. i.e. durability Since the decay of timber is due to the attacks of wood-destroying fungi, and since the most important condition of the growth of these fungi is water, anything which lessens the amount of water in wood aids in its preservation.
2. Seasoning increases the strength of the timber.
3. In the case of treated timber, seasoning before treatment greatly increases the effectiveness of the ordinary methods of treatment, and seasoning after treatment prevents the rapid leaching out of the salts introduced to preserve the timber.
4. The saving in freight where timber is shipped from one place to another.
5. The resilience which the ability to store the stress-energy per unit volume reduces after seasoning.
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Concrete, Cement, Timber, Sand, Workabilty and Aggregates, stones- Building Material
Cement and its type mcq
Identify the correct statements.
- i. Expanding cement is used for filling the cracks
- ii. White cement is mostly used for decorative works
- iii. Portland Pozzolana cement produces less heat of hydration
- iv. High strength Portland cement is produced from the special materials
Expanding Cement: It is obtained from mixing sulpho-aluminate. It has a property to expand, thus used in the elimination of shrinkage cracks. It is used in the treatment of expansion joints and for grouting.
White Portland cement: The white colour of this cement is due to less proportion of iron oxide, which is replaced by Sodium Alumino Ferrite. Colouring agents can be added to white cement to produce coloured cement.
Portland Pozzolana Cement: It is formed by inter grinding of OPC clinker to 10% to 25% of pozzolanic material. It produces less heat of hydration and offers greater resistance to the attack of aggressive water than OPC. It is useful in marine and hydraulic constructions.
High strength Portland cement: This cement is produced by a special technique called Macro Defect Free (MDF) innovation. In this process 4-7% of one of several water-soluble polymers (such as hydroxypropyl methylcellulose, polyacrylamide of hydrolyzed polyvinyl acetate is added for generating high strength.
Rounded aggregate is not suitable for concrete.
Classification of aggregates on basis of shape –
Angular aggregates -
Flaky aggregates -
Elongated aggregates -
Flaky and elongated aggregates -
Important Point:
Modulus of rupture:
Compressive strength of concrete:
Colored cement:
Portland slag cement:
Major compounds of cement clinker (also known as Bogues compounds) are:
Non-destructive Tests
Destructive Test
Different type of strength of timber:
Compressive strength:
Tensile strength:
Timber:
Bulking of Sand:
Resins:
Vee - Bee Consistometer
Efflorescence:
Stones
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Shear strength of TImber is highest in the direction of - Building Material
Shear strength of Timber mcq
The strength of any timber is highest in direction of
- an angle of 60 degree to grains
- an angle of 0 degree to grains
- an angle of 90 degree to grains
- an angle of 120 degree to grains
Wood has three principal axes namely longitudinal, tangential and radial axes. Since it is orthogonal material m it has three values of modulus of elasticity varying by as much as 150 to 1, three shear moduli varying from 20 to 1, and six Poisson’s ratios varying by 40 to 1.
For different strength:
a) Compressive strength: The compressive strength is found to be highest when acting parallel to the axis of the growth. However compressive strength perpendicular to fibres of wood is much lower than that parallel to fibres of wood. Compressive strength parallel to fibre varies from 30.0 to 77.5 N/cm2.
b) Tensile strength: Tensile strength along direction parallel to the grain is found to have greatest strength that can be developed under any other kind of stress. Tensile strength parallel to fibres is of the order 80.0 to 190.0 N/cm2.
c) Shearing strength: Resistance to shear in across direction is found 3 to 4 times greater than that along fibres. The shear strength along fibre is found of the order 6.5 to 14.5 N/mm2.
∴ The strength of timber is highest in the direction of an angle of 0° to the grains.
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Building Material
The calcination of pure lime result in:-
- quick lime
- hydraulic lime
- hydrated lime
- fat lime
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Building Material
Admixtures for concrete
Important points:
The two most popular type of admixture added in concrete are as follows:
Retarder:
Accelerators:
Example: calcium chloride, silicates, Fluorosilicates, Triethanolamine etc.
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The impurity of mixing water which affects the setting time and strength of concrete - Building Material
The impurity of mixing water which affects the setting time and strength of concrete is _____.
- sodium sulphates
- sodium chlorides
- sodium carbonates and bicarbonates
- calcium chlorides
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Building Material
Brick
Clay bricks are classified as first-class, second class, third class and fourth class based on their physical and mechanical properties.
First Class Bricks:
1. These are thoroughly burnt and are of deep red, cherry or copper color.
2. The surface should be smooth and rectangular, with parallel, sharp and straight edges and square comers.
3. These should be free from flaws, cracks, and stones.
4. These should have a uniform texture.
5. No impression should be left on the brick when a scratch is made by a fingernail.
6. The fractured surface of the brick should not show lumps of lime.
7. A metallic or ringing sound should come when two bricks are struck against each other.
8. Water absorption should be 20% of its dry weight when immersed in cold water for 24 hours.
9. The crushing strength of the brick should not be less than 10 N/mm2. This limit varies with different Government organizations around the country.
Uses: First class bricks are recommended for pointing, exposed face work in masonry structures, flooring and reinforced brickwork.
Second Class Bricks are supposed to have the same requirements as the first-class ones except that
Third Class Bricks are under burnt. They are soft and light-colored producing a dull sound when struck against each other. Water absorption is about 25 percent of dry weight.
Fourth Class Bricks are over burnt and badly distorted in shape and size and are brittle in nature.
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Ferrocement and Properties: Lightweight, Durable, and Sustainable Solutions
Ferro cement and Its Properties
Introduction
- Impervious nature
- Capacity to resist shock
- No need of formwork
- Strength per unit mass is high
- Ferro cement developed by P.L. Nervi, an Italian architect, and engineer, in 1940. It consists of closely spaced wire meshes which are impregnated with rich cement mortar mix.
- The wire mesh is usually of 0.5 to 1.0 mm diameter wire at 5 mm to 10 mm spacing and cement mortar is of the cement-sand ratio of 1: 2 or 1: 3 with water/cement ratio of 0.4 to 0.45.
- The ferro cement elements are usually of the order of 2 to 3 cm in thickness with 2 to 3 mm external cover to the reinforcement. The steel content varies between 300 kg to 500 kg per cubic meter of mortar.
- The basic idea behind this material is that concrete can undergo large strains in the neighbourhood of the reinforcement and the magnitude of strains depends on the distribution and subdivision of reinforcement throughout the mass of concrete.
- It is impervious in nature, has the capacity to resist shock and no formwork is required to gain initial strength.
- The main advantages are the simplicity of its construction, a lesser dead weight of the elements due to their small thickness, its high tensile strength, fewer crack widths compared to conventional concrete, easy repairability, noncorrosive nature and easier mouldability to any required shape.
In-depth Knowledge of Ferro-cement
Definition
Ferrocement is a construction material that consists of a combination of cement mortar and a mesh of metal, usually steel, which can be used to create thin-section structures.
Here are some key points about ferrocement:
Composition:
- Ferrocement is composed of a mortar mix (cement, sand, and water) reinforced with layers of mesh or metal.
- The mesh used in ferrocement is typically made of metal, such as steel, and is carefully arranged to form a strong and durable structure.
Applications:
- Ferrocement is versatile and can be used in various construction applications, including boat building, water tanks, pipes, roofs, and even sculptural elements.
- Its ability to form thin and complex shapes makes it suitable for applications where traditional materials might be less practical.
Advantages:
- Ferrocement structures are known for their strength and durability.
- They are relatively lightweight compared to traditional concrete structures.
- The construction process allows for intricate shapes and designs.
- Ferrocement structures can be more resistant to cracking than conventional concrete due to the distributed reinforcement.
Construction Process:
- The construction of ferrocement involves layering the mesh and applying cement mortar.
- The layers are built up gradually, with each layer allowing for the incorporation of the reinforcement into the structure.
- Proper curing is essential to achieve the desired strength and durability.
Uses in Water-related Structures:
- Ferrocement is commonly used in the construction of water tanks, boats, and even swimming pools.
- Its ability to resist corrosion makes it suitable for applications involving water exposure.
Challenges:
- Quality control in construction is crucial to ensure uniform thickness and proper bonding between the mortar and reinforcement.
- Proper curing and workmanship are essential to achieving the desired structural integrity.
Ferrocement offers a unique set of properties that can be advantageous in specific applications, and its use requires careful consideration of the intended structure and appropriate construction techniques. If you have more specific questions or if there's a particular aspect of ferrocement you'd like to ask further in comment section, feel free to ask!
Worldwide use of Ferro-cement
While ferrocement is not as widely used as some other construction materials in large-scale structures, it has found application in various projects around the world. Here are a few examples:
Pleasure Island Boats (Italy):
Ferrocement Yachts:
Ferrocement Water Tanks:
Boat Hulls and Marine Structures:
It's important to note that ferrocement, while offering advantages in specific situations, is not as commonly used in large-scale structures as materials like reinforced concrete. The examples mentioned typically involve smaller-scale applications where ferrocement's unique properties, such as its ability to form complex shapes and resistance to corrosion, are particularly beneficial.
Some additional key points
Here are some additional key points that may contribute to a deeper understanding of ferrocement:
Thin-Section Construction:
- One of the defining characteristics of ferrocement is its ability to create thin-section structures. This is achieved by using a relatively small thickness of mortar reinforced with a mesh. The thin sections contribute to the material's flexibility and versatility.
Flexibility and Shaping:
- Ferrocement allows for the construction of structures with intricate shapes and curves. This is particularly advantageous in applications such as boat building, where streamlined and customized designs are often desired.
Reinforcement Mesh Types:
- Various types of mesh can be used as reinforcement in ferrocement, including chicken wire, hexagonal wire mesh, and woven steel mesh. The choice of mesh depends on the specific requirements of the project.
Construction Techniques:
- The construction process typically involves layering the reinforcement mesh and applying mortar to each layer. The layers are built up gradually, with attention to proper compaction and bonding between layers to ensure structural integrity.
Corrosion Resistance:
- Ferrocement exhibits good resistance to corrosion, making it suitable for applications in marine environments and water-related structures. This property is attributed to the protective alkaline environment created by the cement.
Applications in Developing Countries:
- Ferrocement has been explored as a cost-effective building material in developing countries. Its affordability, ease of construction, and durability make it a potential solution for housing, water storage, and other infrastructure needs.
Research and Advancements:
- Ongoing research and advancements in materials science continue to explore ways to enhance the properties of ferrocement, including improving its strength, durability, and crack resistance.
Combination with Other Materials:
- In some cases, ferrocement is used in combination with other materials to create hybrid structures that leverage the benefits of both. For example, combining ferrocement with foam insulation can result in lightweight yet sturdy panels.
Energy Efficiency:
- The relatively low thermal mass of ferrocement can contribute to energy efficiency in buildings. It may respond quickly to temperature changes, potentially reducing the need for extensive heating or cooling.
Remember that ferrocement, while offering unique advantages, is not a one-size-fits-all solution. Its suitability depends on the specific requirements of the project, and proper construction practices are essential to realizing its full potential.
Density of high-density Concrete - Building material
13. Density of high-density concrete is about ________
- 2400 kg/m3
- 2750 kg/m3
- 3000 kg/m3
- 3360 kg/m3
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Building material
12. The test most suitable for concrete of very low workability is
- Permeability test
- Compaction factor test
- Vee bee test
- Compression test
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Workability of Concrete - Building Materials
Workability of concrete
- The ease and homogeneity with which a freshly prepared concrete can be mixed, placed, compacted and finished are called workability.
- For low workability concrete, the most suitable test is either Vee-bee Consistometer test or the Compaction factor test.
- Of which, Vee bee consistometer is adopted for concrete with even lower workability as compared to that for compaction factor test.
Important Points:
- For highly workable concrete, the most suitable test is a flow table test.
- For medium workable concrete, the slump cone test is favorable.
- J-Ring Test is conducted to check whether the given concrete sample is self-compacting concrete or not.
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Building material - PAINT - MCQ
1.Distemper is a type of
- Oil Paint
- Plastic Paint
- Water Paint
- Enamel Paint
2.The paint used for automobiles is
- Oil Paint
- Plastic Paint
- Water Paint
- Enamel Paint
3.Linseed oil is used as
- Vehicle
- Base
- Thinner
- Drier
15 More MCQ abouts Paint building materials
Building Material
Building Material - PAINT - MCQ
4%
6%
8%
- Base
- Vehicle
- Solvent
- filler
- Base
- Vehicle
- Solvent
- filler
- Base
- Vehicle
- Solvent
- filler
- Oil Paint
- enamel Paint
- aluminium Paint
- Plastic Paint
- (a) iron oxide
- (b) red lead
- (c) titanium white
- (d) any one of the above
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Building Material - PVCN full form - PAINT
Building Material
Building Material
Building Material
6. The penetration test on bitumen is used for determining its
Choose answer
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