MCQs on Design Philosophy and Beams

In the working stress method, the design is based on:

• Ultimate load capacity

• Elastic theory

• Plastic theory

• Limit state concept

The ultimate load method is also known as:

• Strength design method

• Service load method

• Elastic method

• Limit state method

The limit state method ensures:

• Maximum strength only

• Serviceability and safety

• Economy only

• Minimum cost

In a balanced section, the steel and concrete:

• Fail simultaneously

• Steel fails before concrete

• Concrete fails before steel

• Neither fails

An under-reinforced beam section is designed so that:

• Steel yields before concrete crushes

• Concrete crushes before steel yields

• Both fail at the same time

• Steel never yields

In an over-reinforced beam:

• Ductile failure occurs

• Steel yields first

• Concrete crushes first

• Beam cannot carry load

The partial safety factor for concrete (γc) as per IS 456 for limit state of collapse is:

• 1.0

• 1.5

• 1.15

• 2.0

The partial safety factor for steel (γs) in limit state of collapse is:

• 1.0

• 1.15

• 1.5

• 2.0

The modular ratio in working stress method is given by:

• 280 / 3σcbc

• 280 / σst

• Es / Ec

• 140 / 3σcbc

For Fe 415 steel, the design yield strength (fyd) is:

• 250 MPa

• 500 MPa

• 415 MPa

• 360 MPa