Wapcos Civil Engineer-Water/Wastewater Interview Questions and Answers for Experienced

A water supply scheme project involves designing and implementing a system to provide clean water to a community.

• Identify the water source and assess its quality

• Design a treatment system to remove impurities

• Construct pipelines and storage tanks

• Implement a distribution system to deliver water to households

• Train community members on maintenance and operation of the system

Initial setting time of cement is the time taken by cement to harden and attain a particular strength.

• Initial setting time is determined by Vicat apparatus

• It is the time taken for the cement to lose its plasticity and become hard

• The standard initial setting time for ordinary Portland cement is 30 minutes

• Factors affecting initial setting time include temperature, water-cement ratio, and type of cement

The elongation % of steel fy 500 is approximately 12%.

• Elongation % is the measure of ductility of a material.

• It is the percentage increase in length of a material before it fractures under tension.

• For steel fy 500, the elongation % is approximately 12%.

• This means that the steel can stretch up to 12% of its original length before it breaks.

The amount of cement required for 1 cubic meter varies depending on the concrete mix design.

• The amount of cement needed for 1 cubic meter of concrete varies from 250kg to 600kg depending on the mix design.

• The mix design specifies the ratio of cement to other materials like sand and aggregates.

• For example, a mix design of 1:2:4 requires 400kg of cement per cubic meter of concrete.

• It is important to accurately calculate ...read more

Density of materials: Steel - 7850 kg/m3, Concrete - 2400 kg/m3, Sand - 1600 kg/m3

• Density of steel is higher than that of concrete and sand

• Density of concrete varies depending on the mix design

• Density of sand can vary depending on the source and moisture content

There are various types of structures, including buildings, bridges, dams, tunnels, and towers.

• Structures can be classified based on their purpose, design, and materials used.

• Buildings can be further classified into residential, commercial, and industrial structures.

• Bridges can be classified into beam, arch, suspension, and cable-stayed bridges.

• Dams can be classified into gravity, arch, buttress, and embankment dams.

• Tu...read more

Density is the measure of mass per unit volume of a substance.

• It is a physical property of matter.

• It is calculated by dividing the mass of a substance by its volume.

• Units of density include kg/m³, g/cm³, and lb/ft³.

• Density can be used to identify substances and determine their purity.

• For example, gold has a density of 19.3 g/cm³, while aluminum has a density of 2.7 g/cm³.

There are two types of density construction: compacted and loose.

• Compacted density construction involves compressing the material to increase its density, such as in road construction.

• Loose density construction involves leaving the material in its natural state, such as in landscaping.

• The type of density construction used depends on the intended use of the material and the desired level of compaction.

• Other factors that...read more

Tests for construction joints include visual inspection, water tightness test, and load transfer test.

• Visual inspection to check for proper joint alignment and sealant application

• Water tightness test to ensure no water leakage through the joint

• Load transfer test to verify the joint can handle the intended load

• Other tests may include pull-out test, shear test, and compression test

• Testing frequency and methods may vary d...read more