Focused type

6. Differentiate between shallow foundation and deep foundation.

Shallow Foundation:

1. Located near the surface of the ground.

2. Used when the soil near the surface has adequate bearing capacity.
3. Depth is generally less than 3 meters.
4. Common types include spread footing, slab, and isolated footing.
5. Cost-effective for small buildings.

Deep Foundation:

1. Placed deep below the ground surface.

2. Used when the near-surface soil is weak or has low bearing capacity.
3. Depth is greater than 3 meters.
4. Common types include pile foundations, caissons, and drilled shafts.
5. Used for large, heavy structures.

7. Differentiate between combined footing and strip footing.

Combined Footing:

1. Supports two or more columns.

2. It is used when columns are closely spaced and cannot be isolated.
3. Common in situations where the soil is not strong enough to support
individual columns.
4. It distributes the load more evenly across multiple columns.

Strip Footing:

1. A continuous strip of concrete used to support a line of columns or walls.

2. Used in load-bearing walls.
3. Provides support to multiple columns or a continuous structure.
4. Cost-effective for buildings with continuous walls.
8. Define surveying. Explain types of surveying.

Surveying:
Surveying is the science and art of determining the relative positions of points on,
above, or below the earth's surface. It involves measuring distances, angles, and
elevations to prepare maps, charts, and plans.

Types of Surveying:

1. Land Surveying: Used for measuring and mapping land boundaries and
terrain features.
2. Building Surveying: Focuses on the construction of buildings, assessing the
dimensions and structural integrity.
3. Topographic Surveying: Measures and maps the natural and artificial
features of the earth's surface.
4. Hydrographic Surveying: Involves measuring bodies of water, including
rivers, lakes, and oceans.
5. Mine Surveying: Used to measure and map underground mines.

9. What are the equipments used in surveying?

Common surveying equipment includes:

1. Theodolite: Used to measure horizontal and vertical angles.

2. Total Station: Combines electronic theodolite with an electronic distance
measurement tool.
3. Surveying Compass: Measures horizontal angles.
4. Level: Used for measuring height differences and ensuring horizontal
alignment.
5. Tape Measure: For measuring short distances.
6. Prism and Pole: Used in conjunction with a total station for distance
measurement.
7. GPS/GNSS Equipment: Used for high-accuracy location data and
mapping.

10. Explain water quality parameters?

Water quality parameters assess the physical, chemical, and biological

characteristics of water:

1. pH Level: Measures the acidity or alkalinity of water (range: 0-14).

 2. Dissolved Oxygen (DO): Indicates the oxygen available for aquatic life.
Higher DO is better.
3. Turbidity: Measures the cloudiness of water due to suspended particles.
4. Total Dissolved Solids (TDS): The total concentration of dissolved
substances in water, such as salts and minerals.
5. Hardness: The amount of calcium and magnesium in water, which affects
its ability to form lather with soap.
6. Biochemical Oxygen Demand (BOD): Measures the amount of oxygen
required by microorganisms to decompose organic matter in water.
7. Nitrates and Phosphates: Indicators of water pollution from agricultural
runoff and wastewater.

Long answer type

1 a) Briefly explain the classification of bricks.

Bricks are classified based on various factors such as their manufacturing process, quality,
and the materials used. The classification of bricks can be done as follows:

1. Based on Quality:
o First-Class Bricks: Well-burnt, uniform in shape and size, and strong with a
smooth surface. Used for structural work.
o Second-Class Bricks: Slightly inferior in quality, having small cracks and
less uniformity. Used for non-load-bearing walls or low-strength applications.
o Third-Class Bricks: Poor quality, with irregular shapes and rough surfaces.
These are used in temporary structures or as filler material.
o Fourth-Class Bricks: Broken or over-burnt bricks, used as aggregate for
concrete.
o .

1 b) Explain water absorption and compressive tests of brick.

1. Water Absorption Test:

o Purpose: To determine the porosity and the water retention capacity of the
brick.
o Procedure:
▪ Weigh the dry brick (W1).
▪ Immerse the brick in water for 24 hours.
▪ Remove the brick, wipe it off, and weigh it again (W2).
▪ Calculate water absorption using the formula:
 ▪
▪
Standard: The water absorption should be less than 20% for good-
quality bricks.
2. Compressive Strength Test:
o Purpose: To measure the ability of the brick to withstand compressive loads.
o Procedure:
▪ Place the brick in a compression testing machine.
▪ Apply load at a uniform rate until the brick fails.
▪ Record the maximum load at which the brick fails.
▪ Calculate the compressive strength using the formula:

▪
▪ Standard: The compressive strength of first-class bricks should be at
least 10 MPa.

2 a) Explain tests on coarse aggregate.

Tests on coarse aggregates are important to ensure the strength and durability of concrete.
Some common tests include:

1. Particle Size Distribution (Gradation Test):

o Determines the distribution of particle sizes to ensure uniformity for concrete
mix design.
o Performed using sieves to classify aggregates into different sizes.
2. Impact Test:
o Determines the toughness of the aggregate, or its resistance to sudden shocks.
o The test is performed using an impact testing machine, and the aggregate’s
resistance to impact is measured.
3. Crushing Strength Test:
o Measures the ability of the aggregate to resist crushing under pressure.
o The aggregate is placed under a compression machine, and the maximum load
it can withstand is recorded.
4. Water Absorption Test:
o Measures the amount of water the coarse aggregate can absorb, which affects
the water-cement ratio in concrete.
5. Specific Gravity Test:
o Determines the ratio of the density of the aggregate to the density of water.
o Used to determine the mix proportion of aggregates in concrete.

2 b) Describe briefly the composition of good brick.

A good brick should be composed of the following materials:

 1. Clay (50-60%): Provides plasticity and strength when fired.
2. Silica (20-30%): Helps in making the brick hard and durable.
3. Lime (4-6%): Provides a binding effect and helps in the burning process.
4. Alumina (5-15%): Helps in the formation of bonds during firing and adds strength.
5. Iron Oxide (1-2%): Imparts color to the brick and helps in vitrification.
6. Magnesia (1-2%): Helps in reducing shrinkage and improving strength.

A good brick should have an appropriate mix of these components, which ensures high
strength, durability, and a smooth finish.

3 a) Explain normal consistency test of cement.

The normal consistency test is used to determine the percentage of water required to obtain a
paste that has a normal consistency for cement. This is important for assessing the
workability of cement.

1. Procedure:
o Mix a sample of cement with water to form a paste.
o Place the paste in a Vicat apparatus.
o Use a needle to penetrate the paste.
o Gradually add water until the needle penetrates 5-7 mm from the bottom of the
mold.
o The percentage of water added to the cement is called the normal consistency.
2. Standard: Typically, the normal consistency for ordinary Portland cement is about
30-33%.

3 b) Explain compressive strength test of cement.

The compressive strength test measures the ability of cement to withstand compression.

1. Procedure:
o Prepare cement paste with a specified water-to-cement ratio (usually 0.4 to
0.5).
o Mold the paste into cubes or cylinders.
o Cure the specimens in a water bath for 28 days.
o Place the cured specimens in a compression testing machine.
o Apply load gradually until failure occurs.
o Record the maximum load and calculate the compressive strength using:

o
o Standard: The compressive strength should be at least 33 MPa for 28 days of
curing.
4 a) Explain Le Chatelier’s method for soundness test of cement.

The soundness test is performed to ensure that the cement does not undergo excessive
expansion during the setting process.

1. Procedure:
o A sample of cement paste is made and molded into a disk.
o The disk is placed in a Le Chatelier mold, and the measurement is taken.
o The mold is placed in water for 24 hours, and then the specimen is heated in
boiling water for 3 hours.
o After cooling, the distance between the indicators is measured.
o The expansion should not exceed 10 mm.

4 b) What is reinforcement steel? Explain types of steel.

Reinforcement Steel:
Reinforcement steel, commonly known as rebar, is used in reinforced concrete to provide
strength against tensile forces. It is made of steel bars or mesh and is embedded in the
concrete during construction.

Types of Steel:

1. Mild Steel:
o Low-strength steel, easy to work with.
o Commonly used in less-demanding applications.
2. High-Strength Deformed Steel:
o Steel with surface deformation for better bonding with concrete.
o More suitable for structures subjected to high tensile forces.
3. Stainless Steel:
o Corrosion-resistant steel, used for special applications in corrosive
environments.
4. Torsion Steel:
o Steel designed to resist twisting or torsion, often used in bridges and other
structures subjected to torsional loads.

5 a) What do you mean by shallow foundation?

A shallow foundation is a type of foundation that is constructed near the ground surface,
typically less than 3 meters deep. It is used when the soil has adequate bearing capacity near
the surface to support the structure.

1. Types of Shallow Foundation:

o Slab and Beam Foundation
o Spread Footing
o Slab Foundation
5 b) Describe various footings with neat sketch.

1. Isolated Footing:
o Used for individual columns, with a square or rectangular base.
o Sketch

Column

________
| |
| Footing|
|________|

2. Combined Footing:
o Used when columns are closely spaced and cannot be isolated, it supports
multiple columns with a single footing.
o Sketch:

Column Column
____|______|____
| Footing |
|__________________|

3. Slab and Beam Foundation:

o A reinforced concrete slab supported by beams, used for structures with heavy
loads.

6 a) What is PCC? Write down its uses.

PCC (Plain Cement Concrete):

PCC is a mixture of cement, sand, and aggregates in a certain proportion, without the
inclusion of reinforcement. It is widely used as a base material for structures.

Uses:

• Used for foundation work.

• Flooring.
• Sub-base for roads and pavements.

6 b) What is RCC? Write down its uses.

RCC (Reinforced Cement Concrete):
RCC is a concrete that contains reinforcement bars (rebars) to enhance its tensile strength. It
is used in structures where bending or tensile stresses are significant.

Uses:

• Building foundations.
• Roof slabs and beams.
• Bridges and highways.