### Civil Engineering - Concrete Structure

#### Question - 1

As the cube size increases, the strength of concrete

• A decreases
• B remains constant
• C increases
• D insufficient data

#### Question - 2

Tensile strength of concrete is measured by

• A direct tension test in UniversalTesting Machine (UTM)
• B applying the compressive load along the diameter of cylinder
• C applying the third point load on a prism
• D applying the tensile load along the diameter of cylinder

#### Question - 3

A concrete cube of 15 cm and a cylinder of 150 mm diameter and 300 mm height are tested for compressive strength, the strength of cube compared to cylinder will be

• A higher
• B lower
• C equal
• D difficult to assess

#### Question - 4

The ratio of 7 days and 28 days cube strength is

• A 0.5
• B 0.6
• C 0.75
• D 0.85

#### Question - 5

Tensile strength of concrete is approximately of ...................... the compressive strength of concrete.

• A 3 to 7%
• B 7 to 15%
• C 15 to 22%
• D 22 to 25%

#### Question - 6

The failure strain of concrete under direct compression and under flexure are respectively

• A (0.0035, 0.0020)
• B (0.002, 0.0003)
• C $(\frac{f_ck}{E_c},\frac{0.7\sqrt{f_{ck}}}{E_c})$
• D (0.002, 0.0035)

#### Question - 7

In MIO nominal mix concrete, if the quantity of water used per 50 kg of cement is 40 kg then that used for M15 concrete for same workability will be

• A <40kg
• B =40kg
• C >40kg
• D cannot asses

#### Question - 8

The mean strength of the group of four non-overlapping consecutive cubes, for M30 grade concrete should not be less than

• A 28.3 MPa
• B 33.aMPa
• C 30 MPa
• D 29.5 MPa

#### Question - 9

The yield strength of a twisted bar as compared to an ordinary bar (mild steel) is nearly

• A 50% more
• B 25% more
• C 50% less
• D 25% less

#### Question - 10

Compare to mild steel plain bars, high strength deformed bars are

• A less ductile but more strong
• B more ductile but less strong
• C more ductile and strong
• D equally ductile and more strong