Two Marks Questions and Answers

 TWO MARKS QUESTIONS AND ANSWERS

1. Write about Shallow foundation and deep foundation.

Based on the depth, foundation is broadly classified into two types. If the depth of the foundation is less than or equal to its breadth, then it is called as shallow foundation. If the depth of the foundation is greater than its breadth, then it is known as deep foundation.

2. What is a strip footing?

A strip footing is provided for a load-bearing wall. The width of the footing is generally two three times the thickness of the wall. A strip footing is also provided for a row of columns which are so closely spaced that their spread footings overlap or nearly touch each other. It is more economical to provide a strip footing than to provide a number of spread footings in one line. A strip footing is also known as continuous footing.

3. What is a composite pile?

When the piles are made from more than one material they are known as composite pile. These piles are made from concrete and wood. These piles are used in those areas where the water table is up. These piles are used in such conditions just because concrete and wood both are good water absorbers.

4. What are the factors to be considered for selection of suitable foundation type for a building?

The type of foundation is selected based on the following factors:

❖ Building height

❖ Load condition

❖ Soil type

❖ Type of building (residential, administrative, warehouse)

5. List the types of rubble masonry.

The types of rubble masonry are:

❖ Coursed Rubble Masonry

❖ Uncoursed Rubble Masonry

❖ Dry Rubble Masonry

❖ Polygonal Masonry

❖ Flint Masonry

6. What is Ashlar Masonry?

Ashlar masonry is constructed using accurately dressed stones that possess uniform and fine joints. The thickness of the joints ranges about 3mm which is arranged in various patterns. The size of the stone blocks must be in proportion with the thickness of the walls.

7. Define brick masonry.

Brick masonry is built with bricks bonded together with mortar. For all permanent buildings lime or cement mortars are used. But for temporary sheds mud mortar may be used. Brick masonry strength depends on the type of bond and materials used for construction. They play an important role in providing strength, stability, and durability to the brick masonry.

8. Write about Flemish bond.

In this type of bond each course comprises of alternate header and stretcher. Alternate courses start with stretcher and followed by header. Flemish bond is also known as Dutch bond. To break the vertical joints queen closers are required, if a course starts with header. Every header is centrally supported on the stretcher below it. The thickness of Flemish bond is minimum one full brick.

9. Define Zig-zag bond.

Zig Zag Bond is very similar to herring-bone bond. The only difference is that in this case the bricks are laid in a zig-zag pattern. It is mostly adopted in brick-paved flooring.

10. What do you mean by plastering?

Plastering in buildings refers to the process of applying mortar coats on the surfaces of walls, columns, ceiling to get smooth finish. Plastering covers defective workmanship in the construction of a given piece of masonry; and, also it conceals cheap/unsound quality of material used in building up the masonry. It is only after plastering that an appropriate base is ready to further decorate the surface by white-washing, colour-washing, distempering, or painting.

11. Define Pointing.

Pointing is the process of finishing the exposed joints in the masonry, instead of plastering the entire surface of the masonry. It consists of raking the joints to a depth of 10 mm to 20 mm and filling it with richer mortar mixes. Pointing gives perfection to joints, which is the weaker part of masonry. It also gives aesthetic view of the masonry.

12. Compare between plastering and pointing.

The following are some of the differences between plastering and pointing

Plastering

It is applied on the entire wall surface

It gives smooth surface finish

Defective workmanship in masonry can be covered up by plastering

It acts as a base for white washing works

Pointing

It is done only at the exposed joints

It does not provide smooth surface

Well built masonry work can be shown by doing pointing work at the joints

Further finishing works like white washing cannot be done

13. What are the purpose of Cavity Walls?

The major purposes of cavity walls are as follows:

 ❖ Damp Prevention

❖ Thermal Insulation

❖ Sound Insulation

❖ Efflorescence Prevention

14. What is a Diaphragm wall?

Diaphragm wall is method of creating cast in-situ reinforced concrete retaining wall using slurry supported trench method. They are also known as slurry walls. These walls provide rigid, cost effective solution for permanent retaining wall and shafts with less construction joints.

15. Name the different types of Formwork.

Various types of formwork used in construction are Timber Formwork, Steel Formwork, Aluminum Formwork, Plywood Formwork, Fabric Formwork and Plastic Formwork.

16. Define Shoring

Shoring is a temporary structure used to prevent the collapse of the main under-construction structure. The most commonly shoring support is required during the early stage of construction which is excavation. It is a momentary support, which is used during the repair or original construction of buildings and in excavations.

17. List some of the components of a scaffolding

The components of scaffoldings are standards, ledgers, braces, put logs, transoms, bridle, boarding, guard rail and toe board.

18. What is Underpinning?

Underpinning is a method for repair and strengthening of building foundations. There are situations where a failure in foundation or footing happens unexpectedly after the completion of whole structure. Under such a situation, a remedial method has to be suggested to regain the structural stability. The method of underpinning helps to strengthen the foundation of an existing building or any other infrastructure.

19. Write about pitched roof.

A sloping roof is known as pitched roof. These are suitable in those areas where rainfall/ snowfall are very heavy. The pitched roofs are available in various forms as Gable Roof, Hip Roof, Gambrel Roof, Deck Roof and Mansard or club roof.

20. Define flooring.

Flooring is the permanent covering of a floor using any finishing material applied over the floor structure to provide a walking surface. The purpose of floor is to provide a level surface capable of supporting the occupants of the building, furniture, equipment and some time interior wall.

21. Write about Expansion Joints.

The expansion joint depends upon the context of the change of temperature. These joints are provided when the length of the building is greater than 30m and temperature changes by 50°C then a 10 mm expansion joint is provided. The extent of the structure depends on the coefficient of linear expansion of the material. An expansion joint should be provided at the point where the structure changes its direction.

22. List some of the fire extinguishing equipments.

Every building should have the suitable fire extinguishing equipments depending upon the importance of the building.

(a) Manual fire extinguishing elements

(b) Fire Hydrant

(c) Automatic Water Sprinkler systems

23. Write short notes on Natural Ventilation.

Natural Ventilation is a process where the difference in pressure between air inside and outside a building creates an envelope of circulation. The air filters itself through the windows and doors of the structure. Natural or traditional ventilation systems depend on natural forces such as wind and thermal buoyancy to drive outdoor air throughout the building's openings.

24. What are the different types of air conditioning?

Based on the working conditions and position air conditioning can be broadly classified as follows:

❖ Window air-conditioning system

❖ Split air-conditioning system

❖ Package air-conditioning system

❖ Centralized air-conditioning system

25. How do you explain damp proof course?

Dampness is the presence of hydroscopic or gravitational moisture in the building. One of the basic requirements of the building is that it should remain dry or free from moisture traveling through walls, roofs and doors. The damp proof course (DPC) is generally applied at basement levels, which restricts the movement of moisture through walls and floors.