Structural Design - II (MCQ's Test - 1)

Permissible bending tensile stress in high strength deformed bars of grade 415 N/m beam is

• 190 N/mm^2
• 230 N/mm^2
• 140 N/mm^2
• None of the above

Workability of concrete is influenced most by its<br /><br />

• Water-cement ratio
• Aggregate-cement ratio
• Cement content
• Water content

Which one of the following set of values given the minimum clear cover (in mm) for the main reinforcements in the slab, beam, column and footing respectively, according to IS: 456-2000?

• 20, 25, 40, 50
• 5, 15, 25, 50
• 15, 25, 40, 75
• None

The modulus of rupture of concrete gives

• the direct tensile strength of the concrete
• the direct compressive strength of the concrete
• the tensile strength of the concrete under bending
• the characteristic strength of the concrete

The cylinder strength of the concrete is less than the cube strength because of cause of

• The difference in the shape of the cross section
• The difference in the slenderness ratio of of the specimens
• The friction between the concrete specimen and the steel plate of the testing machine
• The cubes are tested without capping but cylinders are tested with capping

The permissible tensile stress in concrete made of M25 concrete is

• 3.5 N/mm^2
• 60 N/mm^2
• 2.5 N/mm^2
• None of the above

The permissible bending tensile stress in concrete for the vertical wall of an R.C. water tank made of M 25 concrete is

• 8.5 N/mm^2
• 6.0 N/mm^2
• 2.5 N/mm^2
• 1.8 N/mm^2

The characteristic strength of concrete is defined as that compressive strength below which not more than

• 10% of results fall
• 5% of results fall
• 2% of results fall
• None of these

 For avoiding the limit state of collapse, the safety of RC structures is checked for appropriate combinations of Dead Load (DL), Imposed Load or Live Load (IL), Wind Load (WL) and Earthquake Load (EL). Which of the following load combinations is NOT considered?

• 0.9 DL + 1.5 WL
• 1.5 DL + 1.5 WL
• 1.5 DL + 1.5 WL + 1.5 EL
• 1.2 DL + 1.2 IL + 1.2 WL

The partial factor of safety for concrete as per IS: 456-2000 is

• 1.5
• 1.15
• 0.87
• 0.446