Most Asked Civil Engineering Interview Questions
1) What is civil engineering?
Civil engineering is a professional discipline of engineering that works in the field of the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, canals, bridges, dams, airports, sewerage systems, pipelines, structural components of buildings, and railways etc.
2) Which are the different sub-disciplines of civil engineering?
Civil engineering is considered the second-oldest engineering discipline after military engineering. It is traditionally categorized into several sub-disciplines such as following:
- Coastal engineering
- Construction engineering
- Earthquake engineering
- Environmental engineering
- Forensic engineering
- Geotechnical engineering
- Materials science and engineering
- Site development and planning
- Structural engineering
- Transportation engineering
- Municipal or urban engineering
- Water resources engineering etc.
3) Who is known as the father of civil engineering?
George John Smeaton is known as the father of civil engineering. In the era of the industrial revolution in England, civil engineering emerged as one of the most prominent engineering disciplines because of many scientific inventions.
4) How should I introduce myself in civil engineering interview?
You should follow the tips given below for going to a civil engineering interview.
- Go to the interview room with a smile on your face.
- After greeting the interview panel, give details about your name and place. Tell about your family details only if you asked so.
- Tell about your educational details.
- Explain why you want to do this job and about your project in brief.
- Tell about the person who inspired you the most.
- Tell about your interests/hobbies. You can also tell how you spend your time when you are free.
- Tell about your skills and explain why you are best for this job.
- Thanks to the interview panel.
A sample answer:
Good morning sir/madam,
My name is Vivek. I am from Indore. I have completed B.tech in civil engineering from Jaypee College, Indore, with an aggregate of 75%. I have completed HSC from MP College with an aggregate of 70% and SSC from Boys High school, with 72%.
There are five members in my family. My father is a teacher, and my mother is a homemaker. I have two siblings.
About my achievements, I got a certificate in a singing level competition in my school. I got an NSS certificate in my college, which I participated in as a volunteer in my 1st year of engineering.
If I talk about my strengths, I am hardworking, self-motivated and dedicated to my work. I believe in working as a team. I am also a good learner.
My hobbies are making crafts, painting, surfing the net.
As a fresher, I don’t have any working experience, but I will prove once I get the opportunity.
5) What is Cement, and what are the different types of cement?
Cement is a fine gray powder mixed with water and other substances to make mortar or concrete. This is one of the most important building materials used in both residential and commercial construction work.
There are many cement types such as Portland cement, high alumina cement, white cement, sulfate resisting cement etc. But, generally, cement can be categorized into the mainly following two types:
- Ordinary Portland cement: This is available in 33, 43 & 53 grades.
- Blended cement: This is available as PPC or slag cement.
6) What is the role of cement in construction?
In any construction, we have to use sand, bricks, jelly, water, steel and many other raw materials. Cement is used to bind these elements together to provide strength and durability to the construction.
7) Which is the best cement for house construction?
There are many types of cement used in house construction. Cement is mainly classified according to their grades. The cement grades determine the compression strength (Mpa) of the concrete that will attain after 28 days of setting.
There are about 13 types of cement used for construction purposes. These cement are:
- Ordinary Portland Cement (OPC)
- Portland Pozzolana Cement (PPC)
- Rapid Hardening Cement
- Quick setting cement
- Low Heat Cement
- Sulfates resisting cement
- Blast Furnace Slag Cement
- High Alumina Cement
- White Cement
- Colored cement
- Air Entraining Cement
- Expansive cement
- Hydrographic cement
For house construction purpose, the following five types of cement are mainly used:
Ordinary Portland Cement (OPC) 43 Grade Cement: This cement is mainly used for wall plastering works, Non-RCC structures, pathways etc. It gets a compression strength of 43 Mpa (megapascals) in 28 days of setting.
Ordinary Portland Cement (OPC), 53 Grade Cement: This cement is mainly used in RCC and pre-stressed concrete of higher grades, cement grouts, instant plugging mortars etc. This cement is best for fast-paced construction, where the initial strength is to be achieved quickly. It gets a compression strength of 53 Mpa (megapascals) in 28 days of setting. It attains 27 Mpa in 7days compared to 23 Mpa by 43-grade cement.
Portland Pozzolana Cement (PPC): This cement has a higher degree of fineness, impermeable and corrosion-resistant quality that makes the concrete denser in large structures. The initial setting time of this cement is low, but it gains more strength with time. It is used in mass concreting work as well as RCC work.
Portland Slag Cement (PSC): This type of cement is preferred over OPC grade in constructions where the structures are more liable to sulfate and chloride attack. This has an excellent corrosion resistance quality, particularly from saltwater so, it is widely used in coastal regions, sewage disposal, and water treatment plants.
White Cement: This cement is mainly used in decorative designs. It is also used to fill gaps in wall tiles, ceramic bathroom fixtures. The manufacturing process of white cement is different and more complicated when compared to ordinary Portland cement. This is costly than other cement.
8) What is the meaning of grade in cement?
A grade is a number used to indicate the minimum compressive strength gained by the cement-sand mortar mix in 28 days of time. For example, OPC 43 grade cement, OPC 53 grade cement etc. The maximum number of grades shows the cement’s maximum compression strength after the 28 days of setting.
9) What is the chemical composition of the Portland cement?
There are four main compounds in Portland cement. They are:
- Tricalcium Silicate (3CaO · SiO2)
- Dicalcium Silicate (2CaO · SiO2)
- Tricalcium Aluminate (3CaO · Al2O3)
- Tetra-calcium Aluminoferrite (4CaO · Al2O3Fe2 O3)
10) What is the blended cement, and what are the advantages of using blended cement?
Blended cement is obtained by mixing OPC (Ordinary Portland cement) with mineral admixtures or additives like fly ash, slag or silica fumes. These mineral admixtures make the blended cement superior as compared to the conventional OPC category of cement.
The advantages of using blended cement can be categorized into two types:
- Technical advantages
- Environmental advantages
Technical Advantages of using Blended Cement
- Blended cement is smoother than Ordinary Portland Cement (OPC). It provides a finer texture than OPC when mixed.
- It provides more strength than OPC because fly ash and slag cement are significantly stronger than OPC after full setting (more than 28 days) in compressive and flexural stress. It depends on the proportion and quality of the admixture. Silica fume cement sets in even less time, usually 3 to 28 days.
- The permeability is lower in blended cement. It extends its useful life and hardness by reducing the penetration of aggressive water run-off compounds such as sulfates and chlorides, which have increased impact as ordinary cement ages. Silica fume cement allows only 20 percent of the permeability of OPC.
- When we use OPC, if the temperature differences between the concrete surface and its interior are high, it may get weaker, and cracking can occur. So, OPC is not a good choice for the areas where temperatures fall below 40 degrees. Blended cement can reduce peak temperatures and reduce the risk of thermal stress.
Environmental Advantages of using Blended Cement
- Blended cement requires less water in construction.
- Blended cement saves energy because it uses admixtures such as slag, fly ash, which is produced as a byproduct of other industrial processes.
- Blended cement is a good example of the conservation of resources. It uses waste products of steel plants and coal power plants, among others. Using this waste in cement lowers the demand for other components like limestone, silica, and clay, helping to preserve these natural resources.
11) What is the requirement of curves on the road? What are the different types of curves?
Curves are very important in road design. Civil engineers know how to use the right equations to design a road with each of these curves. It is very important to calculate the exact degree of the slope the road needs to be in the curve to keep cars from sliding off the road. There are mainly four types of road curves:
- A simple road curve
- Compound road curve
- Reverse road curve
- Deviation road curve
12) What is concrete?
Concrete is a mixture of cement, sand, stone aggregates (jelly) and water. The proportions of the ingredients are mixed according to the type of construction.
13) What is compacting, and why is it used?
Compacting is the process of making the cement mixture denser by releasing the air from it. When we mix various materials, there will be air which is entrapped between them. We have to remove these air bubbles to make concrete impervious and attain maximum strength. Otherwise, there will be voids in the concrete, which reduce the strength substantially.
14) What is the best way of compacting?
In small construction works, generally, steel rods or paddling sticks are used for compacting, but mechanical vibrators are best for this task. Any compacting device has to reach the bottom of the form and should be small enough to pass between reinforcement rods.
15) What do you understand by reinforced concrete?
Reinforced concrete is a form of concrete where we use steel bars or mesh along with cement, sand, stone aggregates and water to give extra strength to the construction.
16) What are the main responsibilities of a construction manager?
A construction manager has to face the following responsibilities:
- Estimate the total cost of the project.
- Purchase of selected materials.
- Cost control of construction.
- Supervision of the construction.
- Selection of bidders for bidding phase.
- Analysis of proposals.
- Construction contract negotiations.
- Construction Scheduling and Monitoring.
17) What are the potential risk factors a worker can face on the construction site?
There are many potential risk factors a worker can face on the construction site, such as fall from heights, electric shock, scaffold and trench collapse, injuries due to not using personal protective equipment correctly, repetitive motion injuries etc.
18) What is the unit weight of concrete?
The unit weight of concrete can vary depending on the type of aggregates and the number of voids. According to the IS, the unit weight of concrete is 2406.53 kg/m3 or 25KN/m3, and the unit weight of RCC is 2500 kg/m3 or 25KN/m3.
19) What is the unit weight of steel?
The unit weight of steel is 7850 Kg/m3. It is also known as the density of steel.
20) What do you understand by ductility?
Ductility is the ability to deform under tensile stress.
21) How can you describe the projection line is the construction?
We can describe the projection line in the same way as we display the earth on a flat piece of paper.
22) What are the various steps involved in the concreting process?
The main steps involved in the concreting process are as follows:
- Transporting and placement of concrete
23) What are the reinforcements that are used in the process of prestressing?
There are mainly three types of reinforcements used in the prestressing process. They are:
- Spalling Reinforcements.
- Equilibrium Reinforcements.
- Bursting Reinforcements.
24) How can you find the weight of the steel bar used in reinforcement?
We can find the weight of the steel bar used in reinforcement by using the following formula:
Weight of Bar in kg/m = Dsquare/162.2
Here, D is the diameter of the bar in mm.
25) What is a flat slab?
The slab which is supported on columns is only called a flat slab. The flat slab doesn’t have any beams.
26) What is the difference between a one-way slab and a two-way slab?
If the longer span ratio is more than two times of shorter span, it is known as the one-way slab.
- One way slab: Ratio of Longer Span / Shorter span > 2
- If the longer span ratio is less than or equal to two times of shorter span, it is known as the two-way slab.
- Two way slab: Ratio of Longer span/ shorter span <= 2
27) What is the soundness of cement?
The soundness of cement is a property that ensures that the cement does not go through any appreciable expansion or experience any change in volume once it has been set. This process is used to avoid any possibilities of the mortar or concrete from getting disrupted.
28) What is fatigue in construction? Give some examples of structures that may be subjected to fatigue?
Fatigue is a process of gradual damage to a structure that occurs when subjected to cyclic loading (repetitive loading and unloading process). Following are some example of structures that may be subjected to fatigue:
- Heavily loaded bridges
- Hydraulic Presses
- Concrete Reservoirs
- Overhead cranes
- Transmission towers
- Offshore platforms
- Burners, trains etc.
29) What are the different types of slump test indications?
A slump test is used to check the quality of the concrete mixture. It measures the consistency of the fresh concrete before it sets. It is also used to check if the batch of concrete is properly mixed or not. There are three different types of slumps that are used in slump testing:
- True Slump
- Shear Slump
- Collapse Slump
30) What is built-up area and super built-up area?
The built-up area consists of the carpet area and space occupied by walls, pillars, and ducts. In most cases, the built-up area is considered as 10% more of the carpet area.
The super built-up area includes the built-up area and any areas that are used by building amenities such as life passages, lobby, stairs, gym, clubhouse, etc.
31) What are some common types of roofs used in construction?
The most common types of roofs used in house construction are:
- Gable roof
- Shed roof
- Gambrel roof
- Skillion roof
- Folded Plate roof
- Half-hipped roof
- Dutch Hip roof
- A-Frame roof
- Gull wind roof
- Bell cast roof
- Sawtooth roof etc.
32) What is the difference between one-story and two-story buildings?
The building which has only one floor and a roof are called a one-story building. On the other hand, the building which has two floors is called a two-story building.
33) What is a crank length in the slab?
The crank length in a slab is 0.42 D. Here, D is Depth of Slab, specified as top cover – bottom cover.
34) What is the standard height of each floor of the multi-story building?
The standard height of each floor of the multi-story building is 3 meters or 10 feet.
35) What is the length of rising and tread in the staircase?
In a staircase, the length of the rise is generally 150mm to 200mm, and the length of the tread is 250mm to 300mm.
36) What is the standard slope of a staircase?
According to the international standard, the slope or pitch of the stair should be between 25 degrees to 40 degrees.
37) What is the OSHA compliance?
OSHA is an international standard for health and safety followed by every industrial segment and corporate office throughout the U.S.A.
The full form of OSHA is Occupational Safety and Health Act. The main motive of this act is to fulfill the health and safety requirement of employees and workers.
38) What is the considerable capital cost for a construction project?
Following is the list of some possible capital cost for a construction project:
- Land acquisition cost( Assembly, holding and improvement)
- Planning and feasibility studies cost
- Construction material, equipment, and labor cost
- Construction financing cost ( Bank loan)
- Insurance and taxes during construction
- Owner’s general office overhead charges
- Inspection and testing cost
- Equipment and furnishing not included in the construction
- Field supervision, architectural and engineering design
39) What is the composition of a landfill in a construction?
Following are the four critical elements for a secure landfill:
- The bottom liner
- A leachate collection system
- A cover
- Natural hydrogeologic settings
40) Which software is used in the construction sector to estimate the cost and monitoring expenses?
The following software is used to estimate the cost and monitoring expenses in the construction sector:
- Construction partner
- Premier construction software
- Tally System
- Maxwell System
- eTakeoff etc.
41) What are the different types of foundations used in construction?
There are mainly three types of foundation used in construction:
- Basement foundation: In this type of foundation, first, a basement is prepared, and then on top of it, the building is constructed.
- Crawl space foundation: It is a type of raised foundation. It is built above the ground and provides enough space to crawl underneath.
- Slab foundation: In this foundation, concrete is directly poured into the pit made in the ground.
42) What do you understand by the hybrid foundation?
Hybrid foundation is generally used for high rise buildings. It contains both soils supported mat and piles. This type of foundation helps reduce the amount of the settlement.
43) What are the common ways of demolition?
There are mainly three types of demolition used to demolish a construction:
- Pressure Bursting
44) What is the tallest human-made structure in the world?
The world’s tallest human-made structure is the Burj Khalifa in Dubai (of the United Arab Emirates). It is 829.8-metre-tall (2,722 ft).
This residential building gained the official title of “tallest building in the world” and the tallest self-supported structure at its opening on January 9, 2010.
45) Which is a stronger solid steel rod or hollow steel pipe?
As we take them based on weight, steel pipe is stronger in bending and is less likely to buckle in axial compression.
46) What are the main reasons for a building collapse?
There should be several reasons for building collapse. For example,
- Passage of time
- Weak foundations
- Natural calamities like earthquakes, hurricanes, etc.
- Other reasons such as bombing or war destruction also responsible for building collapse.
47) What do you understand by flashing?
Flashing is a type of extended construction done to save the building from water leakage. Flashing is done to seal and protect joints in a building from water penetration at the intersecting roofs, walls and parapets.
48) What are the different types of a slump?
There are mainly three types of a slump:
- True Slump: If the general drop of the concrete mass is evenly distributed all over the surface without disintegration after testing, it is called a true slump.
- Shear Slump: When one-half of the concrete mass slides down, the other is called the shear slump. This type of slump is obtained in a lean concrete mix. Shear slump specifies that the concrete has poor cohesion, and it may get segregation and bleeding. That’s why it is not preferred for the durability of concrete.
- Collapse Slump: If the concrete sample has excessive water added and the sample is collapsed, it is known as collapse slump.
There is another type of slump known as Zero Slump. It is used for very stiff or dry mixes. It does not show any changes in the slump after removing the slump cone.
49) What is grout, and why is it used?
The fluid form of concrete is called grout. It is used to fill the voids in construction.
50) What do you understand by alternate bid?
Alternate bid is the amount stated to be deducted or added from the base bid amount. The alternate bid is used when there is a use of alternate materials or methods of construction.
51) What is the acceptable moisture content in fine aggregate for the concrete mix?
If the moisture content is more than 5% in the aggregate, it is not preferred to use.
52) What is the change order request?
The change order request is a written document issued or given by the owner, requesting an adjustment to the contract sum or an extension of the contract time. Usually, it is issued by the architect or owner’s representative.
53) What is segregation of concrete?
Segregation of concrete is the separation of cement, sand and aggregates of concrete from each other during handling and placement. This is mainly caused due to uneven water-cement ratio or over-vibration or compaction of concrete. Cement paste comes to the top, and aggregates settle at the bottom. It also occurs when concrete is poured about more than 1.5m.
54) What does a construction cost covers and what does not?
A construction cost covers the following things:
- Equipment and services
- Contractor’s overhead and profit
- Other direct construction costs etc.
A construction cost does not cover the following things:
- The compensation paid to the architect, consultant or engineers
- Cost of the land
- Other possible costs related to the owner’s responsibility
55) What is the meaning of the term seepage in construction?
The slow percolation of water through soil is called seepage.
56) What is the compressive strength of a brick used in house construction?
There are three types of bricks used in house construction, which have different
|Types of Bricks
|Second class bricks
57) What is the Critical Path Method (C.P.M) in construction?
The critical path method is a strategy and method used to represent the respective tasks and activities involved in the construction through a symbolic diagram.
58) What is the procedure to check the quality of the cement on the construction site?
There are a few ways to check if the cement is good or not. See the following tips:
- Date of manufacture: The strength of cement decreases with its age. So, it would be best if you chose the cement which is produced as soon as possible.
- Color: The cement color should be grey with a light greenish shade, and it should be uniform. The color indicates the excess of lime or clay in the cement.
- Float test: Good cement doesn’t float if you throw the cement in water.
- Temperature: When you put your hand in a cement bag, it should feel cool.
59) What is the initial and final setting time of the concrete?
The concrete’s initial setting time is 30 minutes, and the final setting time is 10 hours. The strength checking of concrete is generally done after 28 days of setting.
60) What do you understand by durability?
Durability is the ability to withstand under the pressure of a certain strength.
61) What do you understand by bleeding of concrete?
Bleeding of concrete is a form of segregation, where water is separated and comes out from the cement, sand and aggregates of concrete to the surface. This is mainly caused due to uneven water-cement ratio or over-vibration or compaction of concrete. There is also a reason as water has the lowest specific gravity among all the ingredients of concrete.
62) What is the use of a zoning permit in construction?
A zoning permit is a document issued by governing urban authority to the contractors permitting that the land is used for a particular purpose.
63) What is soil analysis?
Soil analysis is a process of testing soil to determine its nutritional and elemental composition. This testing is done to know the contents of nitrogen, potassium and phosphorous in the soil.
64) Why is soil analysis required for construction?
When the construction company starts the construction, they assign soil engineers to test the soil’s composition to determine if it is strong soil or weak soil. Only the strong soil is used for building construction. Strong soil is the type of soil that does not expand or contract when exposing to moisture, and it has a good density. This is essential for long-lasting construction.
65) What is the difference between a total station and a theodolite?
A total station uses a GPS, lasers, and leveling sensors to measure precise elevations and distances to develop point clouds. On the other hand, the theodolites or auto levels can detect the change in elevation between two points without distance measurements.
66) Why the leaning tower of Pisa has not fallen over yet?
The Leaning Tower of Pisa is a beautiful piece of geotechnical engineering. This tower is not collapsed yet because the engineers who made this tower have placed weights on the north end of the foundation to balance the structure. Now, it is believed that the structure will survive for hundreds of more years.
67) What are some common issues of the clients that an architect has to face?
There are some common problems of the client that an architect has to face:
- When the clients are unsure what they want, their confusion may create a problem for the architect.
- When the client has a tight and limited budget
- When the client asks for a custom design at a standard design cost
- When an architect has to work with limited space
68) What are the different types of roofs?
Following are the different types of roofs used in house construction:
- Half hipped roof
- Mansard roof
- Dutch gable roof
- Bell cast roof
- Skillion roof
- Gambrel roof
- Gull wind roof
- Sawtooth roof
- Monitor roof, etc.
69) What is the difference between absorption, adsorption, and sorption?
Absorption is when an atom, molecule or ions enter any bulk phase like gas, solid or liquid. In this process, the energy of a photon is transferred to another entity. On the other hand, adsorption occurs when the gas or liquid solute accumulates on the solid’s surface. So, adsorption is also similar to absorption, but it refers to the surface rather than a volume.
The main difference between absorption and adsorption is that one is a bulk process, and the other is a surface process. Sorption describes the actions of absorption and adsorption both.
70) What is the role of compacting in concrete?
The role of compacting in concrete is very important. When we mix various materials with cement, some air bubbles are entrapped between them. We have to remove these air bubbles to make concrete impervious and attain maximum strength. Otherwise, these air bubbles would form voids in the concrete, which reduce the strength substantially. That is why compacting important.
71) What is the best way of compacting?
There are several ways which we can do for compacting. For example, we can use steel rods or paddling sticks, but mechanical vibrators are best for compacting. A compacting device is considered the best device which reaches the bottom of the form and should be small enough to pass between reinforcement rods.
72) What is curing, and how is it done?
Curing is a process of maintaining a favorable environment for moisture retention in concrete or supplying of water shower to the concrete from an external source. We have to sprinkle water from the top to curing the newly constructed walls and kept them wet. It is good for the slab or roof to make ponds of 1m x 1m and gently pour sufficient water. Beams and columns should be kept wet by covering a wet sack over them.
73) How many days should the curing is done normally?
We should start curing just after the surface becomes dry, and we should do it for at least 21 days.