10+ Assistant Highway Engineer Interview Questions and Answers

I have experience working with various pavers including Caterpillar, Volvo, and Dynapac.

• I have used Caterpillar pavers on a highway resurfacing project in my previous job.

• I have also worked with Volvo pavers on a bridge construction project.

• Dynapac pavers were used on a road widening project that I was a part of.

• I am familiar with the features and capabilities of each of these pavers.

The maximum speed of paver during DBM laying should be around 2-3 km/h to ensure proper compaction and quality of the road surface.

• The maximum speed of the paver should be controlled to allow for proper compaction of the DBM layer.

• Excessive speed can lead to inadequate compaction, resulting in a weaker road surface and potential future issues.

• A speed of 2-3 km/h is generally recommended for DBM laying to achieve optimal compaction and quality.

• It is important for the operator ...read more

The maximum camber in the superelevation portion of a highway is the maximum slope or tilt of the road surface.

• Camber is the slope provided to the road surface to counteract the centrifugal force acting on vehicles during turns.

• Superelevation is the banking of the road at curves to allow vehicles to safely negotiate the turn at higher speeds.

• The maximum camber in the superelevation portion is determined by various factors such as design speed, curve radius, and vehicle charac...read more

The width of a 4-lane highway can vary, but it is typically around 60 to 80 feet.

• The width of a 4-lane highway depends on various factors such as traffic volume, design standards, and available space.

• In urban areas, the width can be narrower, around 60 to 70 feet, while in rural areas it can be wider, around 70 to 80 feet.

• Additional width may be required for shoulders, medians, and barriers.

• Specific design guidelines and regulations determine the exact width of a 4-lane highw...read more

Highways are typically composed of multiple layers to ensure durability and stability.

• Highway layers include subgrade, subbase, base, and surface layers.

• Subgrade is the natural soil or rock beneath the highway.

• Subbase layer is added to improve the strength and stability of the subgrade.

• Base layer provides additional strength and support to the pavement structure.

• Surface layer is the topmost layer that provides smoothness and skid resistance.

• Different materials like asphalt, c...read more

PQC laying refers to the process of laying a Pavement Quality Concrete (PQC) layer on a highway.

• Prepare the subgrade by compacting and leveling the surface.

• Place a layer of granular sub-base material and compact it.

• Construct the edge forms to define the boundaries of the PQC.

• Pour the PQC mix onto the prepared surface and spread it evenly.

• Use a paver machine or manual methods to level and compact the PQC.

• Cure the PQC by applying water or curing compounds.

• Ensure proper jointing...read more

The laying temperature for DBM (Dense Bituminous Macadam) typically ranges from 140 to 160 degrees Celsius.

• Laying temperature for DBM is crucial for achieving proper compaction and bonding of the material.

• The temperature range of 140-160 degrees Celsius ensures that the DBM is workable and can be compacted effectively.

• Excessive heat can lead to premature cooling and inadequate compaction, while lower temperatures may result in poor bonding and durability.

• It is important to mo...read more

The maximum speed of a compactor varies depending on the type and model, but typically ranges from 2 to 6 miles per hour.

• The maximum speed of a compactor is usually between 2 to 6 miles per hour.

• The speed can vary based on the type of compactor (e.g. vibratory, smooth drum) and the model.

• Higher speed compactors are often used for larger projects where efficiency is key.

• Lower speed compactors are used for more precise compaction in smaller areas.

Slump is the required consistency of PQC (Pavement Quality Concrete) for proper construction.

• The required slump for PQC typically ranges from 20-40 mm.

• Slump test should be conducted at the site to ensure the correct consistency.

• Proper slump ensures good workability and strength of the concrete.

• If the slump is too high, it may lead to segregation and bleeding issues.

• If the slump is too low, it may result in difficulty in placing and compacting the concrete.

The bitumen percentage in Dense Bituminous Macadam (DBM) typically ranges from 5-7%.

• Bitumen percentage in DBM is usually around 5-7%

• The exact percentage may vary based on the specific mix design and project requirements

• Higher bitumen content provides better durability and resistance to weathering

• Lower bitumen content may result in a more rigid mix but may be prone to cracking

• Proper testing and quality control measures are essential to ensure the correct bitumen percentage

Dowel bars are used in PQC to transfer load and prevent faulting in joints.

• Dowel bars help in transferring loads between adjacent slabs, reducing stresses at joints

• They prevent faulting by maintaining alignment and load transfer across joints

• Improves overall performance and durability of the pavement

• Commonly made of steel or fiberglass materials

The stages in DPR of a road project include survey and investigation, planning and design, preparation of estimates, approval, and construction.

• Survey and investigation to gather data on existing conditions

• Planning and design to determine alignment, cross-section, and other details

• Preparation of estimates for cost analysis

• Approval from relevant authorities

• Construction phase to execute the project

Superelevation is the banking of a road or railway track around a curve to counteract the effects of centrifugal force.

• Superelevation is the tilt or slope provided to the outer edge of a road or railway track on a curve.

• It helps vehicles or trains to navigate the curve at higher speeds safely by counteracting the centrifugal force.

• The amount of superelevation required depends on factors like design speed, curve radius, and friction between tires/wheels and road surface.

• Excess...read more

Soil stabilizer is a chemical or mechanical additive used to improve the properties of soil.

• Soil stabilizers can improve soil strength, durability, and resistance to erosion.

• Chemical stabilizers include lime, cement, and asphalt emulsions.

• Mechanical stabilizers include geotextiles and grids.

• Soil stabilizers are commonly used in road construction and building foundations.