Johnson Electric Interview Questions and Answers

The spacing of main bar and distribution bar depends on the design and load requirements of the structure.

• The spacing is determined by the structural engineer during the design phase.

• It varies depending on the size and shape of the structure, as well as the load it will bear.

• The spacing should be such that the reinforcement is evenly distributed throughout the structure.

• For example, in a slab, the spacing of main bars may be 150mm to 200mm apart, while the distribution bars m...read more

IS code for RCC is IS 456:2000 and for mix design of concrete is IS 10262:2009.

• IS 456:2000 provides guidelines for the design and construction of reinforced concrete structures.

• IS 10262:2009 provides guidelines for the proportioning of concrete mixes based on the desired strength and workability.

• Both codes are important for ensuring the quality and durability of concrete structures.

Mixing time in concrete is the duration required to achieve a homogeneous mixture of all the ingredients.

• Mixing time depends on the type of mixer used.

• It also depends on the quantity of ingredients and their properties.

• The ideal mixing time is usually specified by the manufacturer or as per the design requirements.

• Over-mixing can lead to a decrease in the strength of concrete.

• Under-mixing can result in the formation of voids and weak spots in the concrete.

The question is about the required materials and steel BBS, layout, and quantity of material for construction purposes.

• The required materials for construction depend on the type of project and its specifications.

• Steel BBS (Bar Bending Schedule) is used to determine the quantity of steel required for a project.

• Layout refers to the plan or design of the project, including the placement of materials and structures.

• Quantity of material required for construction can be calculated ...read more

Dedo is a term used in construction for the leveling of the foundation of a building.

• Dedo is the process of marking the level of the foundation of a building.

• It is done to ensure that the foundation is level and stable.

• It is usually done using a spirit level and a measuring tape.

• Dedo is important for the safety and stability of the building.

• It is also important for the proper alignment of walls and columns.

• For example, if the dedo is not done properly, the walls may not be st...read more

The question covers various aspects of concrete testing and steel reinforcement.

• Slump test is used to measure the consistency of fresh concrete.

• Density of cement is the mass per unit volume of cement.

• Steel diameter has a minimum and maximum limit as per the design specifications.

• The minimum and maximum diameter of steel reinforcement bars depend on the type of structure and the load it will bear.

Workability is the ease with which a material can be worked or shaped.

• Workability is an important factor in construction materials such as concrete and mortar.

• It is affected by factors such as water content, aggregate size and shape, and temperature.

• A material with good workability is easy to mix, place, and finish.

• For example, a concrete mix with high workability can be easily poured into formwork and will flow to fill all the corners and gaps.

• On the other hand, a mix with l...read more

M20 is a grade of concrete used in construction, indicating its compressive strength.

• M20 is a mix of concrete with a compressive strength of 20 megapascals (MPa).

• It is commonly used for residential and commercial construction projects.

• The mix proportion for M20 concrete is 1:1.5:3, which means 1 part cement, 1.5 parts sand, and 3 parts aggregate (stone).

• M20 concrete is suitable for foundations, beams, columns, and slabs.

• Higher grade concretes like M25, M30, etc., have higher ...read more