250mm by 400mm rectangular beam is reinforced with 3-20 mm diameter bars, f’c=35 MPa, fy=345 MPa, diameter of stirrups=10mm, and concrete cover=40mm. Calculate the effective depth of the beam. i. 340 mm j. 320 mm k. 300 mm l. 330 mm

15. A 250mm by 400mm rectangular beam is reinforced with 3-20 mm diameter bars,

f’c=35 MPa, fy=345 MPa, diameter of stirrups=10mm, and concrete cover=40mm.

Calculate the effective depth of the beam.

i. 340 mm

j. 320 mm

k. 300 mm

l. 330 mm

16. A 250mm by 400mm rectangular beam is reinforced with 3-20 mm diameter bars,

f’c=35 MPa, fy=345 MPa, diameter of stirrups=10mm, and concrete cover=40mm.

Calculate the depth of compression block in the beam.

m. 54.648 mm

n. 45.446 mm

o. 43.718 mm

p. 50.025 mm

17. A 250mm by 400mm rectangular beam is reinforced with 3-20 mm diameter bars,

f’c=35 MPa, fy=345 MPa, diameter of stirrups=10mm, and concrete cover=40mm.

Calculate the depth of neutral axis in the beam.

m. 43.718 mm

n. 45.446 mm

o. 54.648 mm

p. 50.025 mm

18. A 250mm by 400mm rectangular beam is reinforced with 3-20 mm diameter bars,

f’c=35 MPa, fy=345 MPa, diameter of stirrups=10mm, and concrete cover=40mm.

Calculate the strain at the extreme layer of steel.

i. 0.01134

j. 0.01235

k. 0.01565

l. 0.01889