RRB JE Civil Questions with Detailed Solutions

Correct Answer: C) Awning window

An awning window is a type of window that is hinged at the top and opens outward from the bottom. This design allows ventilation even during light rain, as the outward-opening sash acts like an awning and prevents rainwater from entering.

·         A) Casement window – Usually hinged at the side and opens inward or outward like a door.

·         B) Pivot window – Rotates about a central pivot point, either horizontally or vertically.

·         D) Sliding window – Opens by sliding the shutters horizontally or vertically along tracks.

Since an awning window is hinged at the top and opens outward, the correct answer is:

C) Awning window

Correct Answer: D. Decreases

Explanation:

For concrete cylinders subjected to compression, the measured compressive strength is influenced by the height-to-lateral dimension ratio (H/D ratio) of the specimen. As this ratio increases, the specimen becomes more slender.

In shorter specimens, the friction between the loading platens of the testing machine and the ends of the specimen provides lateral restraint. This restraint creates a confining effect that increases the apparent compressive strength. As the height-to-lateral dimension ratio increases, the influence of this end restraint decreases, resulting in a lower measured compressive strength.

Therefore, for slender cylinders, an increase in the height-to-lateral dimension ratio leads to a decrease in the measured compressive strength.

Explanation of Other Options:

A. Remains Constant

The compressive strength does not remain constant with changes in specimen geometry. The height-to-lateral dimension ratio affects the measured strength.

B. Increases

An increase in slenderness does not increase compressive strength. In fact, the reduction in end restraint causes the measured strength to decrease.

C. First Increases, Then Decreases

There is no such general trend for concrete compression specimens. The measured compressive strength decreases as the height-to-lateral dimension ratio increases.

Conclusion:

As the height-to-lateral dimension ratio of a concrete cylinder increases, the measured compressive strength decreases due to the reduction in the confining effect provided by the testing machine platens.

Answer: D. Decreases.

Correct Answer: D. Piston Pump

Explanation:

In Ready Mix Concrete (RMC) construction, piston pumps are most commonly used for conveying concrete from the mixer to the point of placement. These pumps operate by means of reciprocating pistons that create pressure to push concrete through pipelines over long horizontal distances and significant vertical heights.

Piston pumps are capable of handling concrete containing coarse aggregates and can deliver concrete continuously with high efficiency. They are widely used in:

• High-rise building construction
• Bridges and flyovers
• Tunnels
• Large concrete structures

The pumping action ensures rapid placement of concrete while maintaining uniformity and reducing manual handling.

Correct Answer: C. 50 to 100 mm

Explanation:

The slump test is used to determine the workability and consistency of fresh concrete. The required slump depends upon the type of construction, method of placement, degree of compaction, and congestion of reinforcement.

For beams and slabs, a medium workability concrete is generally required so that the concrete can be placed and compacted properly around the reinforcement without segregation. Standard practice recommends a slump range of 50 mm to 100 mm for such reinforced concrete members.

The commonly adopted slump ranges for various types of work are given below:

Thus, for beams and slabs requiring medium workability, the recommended slump range is 50 mm to 100 mm.

Answer: A. Aluminium sheet roofing

Explanation:

Roofing materials are often classified as lightweight or heavyweight based on their dead load. Lightweight roofing materials impose less load on the supporting structure and are therefore preferred for industrial buildings, sheds, warehouses, and long-span structures.

Aluminium sheet roofing is considered a lightweight roofing material because aluminium has low density and high strength-to-weight ratio. It is durable, corrosion-resistant, easy to install, and places only a small dead load on the roof structure.

The other options are classified as heavier roofing systems:

• Slate tile roofing is comparatively heavy due to the weight of natural stone tiles.
• Flat clay tile roofing is heavier than metal sheet roofing.
• Madras terrace roofing is a traditional roof construction consisting of brick and mortar layers and is classified as a heavy roof.

Therefore, among the given options, aluminium sheet roofing is classified as lightweight roofing.

Correct Option: A. Aluminium sheet roofing

Correct Answer: D. Tremie Method

Explanation:

The Tremie method is the most commonly used technique for placing concrete underwater. In this method, concrete is poured through a vertical pipe called a tremie pipe, whose lower end remains embedded in the freshly placed concrete. This prevents direct contact between the concrete and water, thereby minimizing segregation and washout of cement.

The tremie method is widely used in the construction of:

·         Bridge piers and foundations

·         Well foundations

·         Dams and marine structures

·         Harbor and dock works

The method ensures continuous placement of concrete and produces a dense, homogeneous mass even under water.

Mixing concrete manually is unsuitable for underwater concreting, shotcrete is primarily used for repair and lining works, and roller-compacted concrete is generally used in dams and pavements.

Conclusion:

For underwater concreting, the Tremie method is the most widely adopted and effective method because it allows concrete to be placed without segregation or loss of cement.

Answer: D. Tremie Method.

Correct Answer: B. Absorption Test

Explanation:

The absorption test is a field test conducted to determine the water absorption capacity of a brick. In this test, a dry brick is first weighed and then immersed in water for a specified period, usually 24 hours. After immersion, the brick is taken out, wiped free of surface water, and weighed again.

The percentage increase in weight indicates the amount of water absorbed by the brick. A good-quality brick should not absorb more than the permissible limit specified in the relevant standards. Excessive water absorption indicates high porosity, which may reduce the durability and strength of the brick.

Explanation of Other Options:

A. Hardness Test

The hardness test is conducted to assess the resistance of a brick to abrasion. It is performed by scratching the brick surface with a fingernail or a hard object. No water immersion is involved in this test.

C. Structure Test

The structure test involves breaking a brick and examining its internal structure. A good brick should have a uniform texture and be free from voids, cracks, stones, and lime nodules.

D. Shrinkage Test

The shrinkage test is used to determine the reduction in volume or dimensions of a material due to drying. It is not performed by immersing a brick in water.

Conclusion:

Since the test involves immersing a brick in water for a specified duration to determine the amount of water absorbed, it is known as the absorption test.

Answer: B. Absorption Test.

Correct Answer: D) Bamboo

Detailed Solution

In India, bamboo is the most commonly used material for scaffolding, especially in traditional and small-to-medium construction projects.

Bamboo is preferred because it is:

• Lightweight and easy to handle
• Strong in tension and compression
• Economical and widely available
• Easy to assemble and dismantle

Conclusion

Since bamboo is widely used for scaffolding due to its strength, availability, and low cost, the correct answer is D) Bamboo.

Answer: D. Louvered door

Explanation:

A louvered door consists of a series of inclined horizontal slats, known as louvers, fixed within a frame. These slats permit the free passage of air and light while obstructing direct vision through the door.

Louvered doors are particularly suitable for locations where both ventilation and privacy are required, such as:

• Bathrooms
• Toilets
• Changing rooms
• Utility rooms
• Wardrobes and cupboards

The inclined arrangement of the louvers allows continuous air circulation while maintaining privacy by preventing a clear line of sight.

The other options do not provide the same combination of ventilation and privacy:

• Sliding doors are primarily used for space-saving and do not inherently provide ventilation.
• Paneled doors offer privacy but limited ventilation.
• Flush doors provide privacy and a smooth appearance but do not allow ventilation.

Therefore, the door type that provides the best combination of ventilation and privacy is the louvered door

Answer: B

Improving the workability of the concrete without increasing the water content

Explanation:

Water-reducing admixtures are chemical admixtures added to concrete to reduce the amount of water required to achieve a given workability. These admixtures disperse the cement particles more effectively, resulting in a more workable and cohesive concrete mix without the need for additional water.

The use of water-reducing admixtures provides several benefits:

• Improves workability and ease of placement of concrete.
• Reduces the water-cement ratio for a given workability.
• Increases compressive strength due to the lower water-cement ratio.
• Enhances durability by reducing porosity and permeability.
• Improves the quality and finish of hardened concrete.

Since these admixtures improve workability without increasing the water content, they are widely used in reinforced concrete structures, high-strength concrete, and mass concrete works.

Therefore, the addition of water-reducing admixtures helps in improving the workability of the concrete without increasing the water content.

Correct Answer: D. Arnold

Explanation:

Arnold is the default rendering engine in the latest versions of Autodesk 3ds Max. Arnold is a physically based ray-tracing renderer that provides high-quality rendering with realistic lighting, shadows, reflections, and materials. Autodesk integrated Arnold into 3ds Max beginning with the 2018 release, and it has since become the standard built-in renderer.

Arnold is widely used in architectural visualization, animation, visual effects, and product design because of its accuracy, scalability, and ability to produce photorealistic images.

Explanation of Other Options:

A. Mental Ray

Mental Ray was previously included with Autodesk products and served as the default renderer in older versions of 3ds Max. However, Autodesk discontinued support for Mental Ray, and it is no longer the default rendering engine.

B. V-Ray

V-Ray is a highly popular third-party rendering engine developed by Chaos. Although extensively used for architectural visualization and animation, it is not the default renderer supplied with 3ds Max.

C. Scanline Renderer

The Scanline Renderer is the traditional rendering engine included in older versions of 3ds Max. It provides fast rendering but lacks the advanced photorealistic capabilities of modern renderers such as Arnold.

Conclusion:

Since Arnold is the integrated and default rendering engine in modern versions of Autodesk 3ds Max, the correct answer is:

Answer: D. Arnold

Correct Answer: D) Object Snap

Object Snap (OSNAP) is an AutoCAD feature that allows the cursor to accurately snap to specific geometric points on existing objects, such as:

·         Endpoint

·         Midpoint

·         Center

·         Intersection

·         Quadrant

·         Tangent

·         Perpendicular, etc.

This feature ensures precision while creating and editing drawings.

·         A) Polar Tracking: Helps draw lines at specified angles.

·         B) Snap: Restricts cursor movement to a predefined grid spacing.

·         C) Ortho: Constrains cursor movement to horizontal and vertical directions (90°).

Therefore, the command/setting used to select midpoints, endpoints, and other exact points on objects is Object Snap (OSNAP).

Correct Answer: D. Surface Edit

Explanation:

In Autodesk Civil 3D 2024, the Surface Edit command is used to modify an existing surface by adding, deleting, or editing surface data. Through this command, users can perform operations such as:

• Adding points to a surface
• Deleting points or lines
• Swapping triangle edges
• Raising or lowering surface elevations
• Adding breaklines and boundaries
• Modifying triangulation

These editing tools help refine the surface model and improve its accuracy after the initial surface creation.

The Surface Edit option is available from the Prospector tab of Toolspace under the surface definition and editing tools.

Answer: C. Create Profile

Explanation:

In Autodesk Civil 3D 2024, a profile is created along an existing alignment to represent existing ground levels or proposed design elevations. The process of generating a profile from an alignment is initiated through the Create Profile option available in the Profiles tools.

When the command is executed, Civil 3D opens the Create Profile from Surface dialog box, where the user selects the alignment and the surface from which the profile is to be generated. Thus, the profile creation workflow is commonly referred to as Create Profile.

The term Profile from Alignment is often associated with the profile creation process and may appear in certain menus or dialog boxes, but in many Civil 3D objective-type questions and software-training references, the command is identified as Create Profile.

Therefore, according to the expected answer in the examination context, the correct option is:

Correct Option: C. Create Profile

Answer: D. 3.2 m³

Explanation:

The quantity of earthwork excavation for a foundation is calculated by multiplying the area of excavation by the depth of excavation.

Given:

• Base area of footing = 4 m²
• Depth of footing = 0.8 m

Calculation:

Quantity of earthwork = Area × Depth

= 4 × 0.8

= 3.2 m³

Since the question does not specify any additional excavation for working space, side slopes, or offsets, the excavation volume is taken as equal to the plan area of the footing multiplied by the depth.

Therefore, the quantity of earthwork required for the foundation is 3.2 m³.