Unit 9 Module: Determine the Compressive Strength of Concrete Hollow Blocks

Question 1

are the most common materials for walling in building construction
because of their availability, low cost and their ease in installation.

Answer 1

Concrete hollow blocks (CHB)

Question 2

are classified as bearing and nonbearing blocks and are compressive materials, fill with mortar in their hollow part, spread by mortar per
layer and reinforced horizontally and vertically to increase their resistance lateral forces.

Answer 2

Concrete hollow blocks (CHB)

Question 3

Load bearing
blocks ranges from ___ to ___ and are used to carry load aside from its own weight

Answer 3

15 cm, 20 cm

Question 4

non-bearing
blocks are intended for walls, partition, fences or dividers carrying its own weight with thickness ranges
from ___ to ___ .

Answer 4

7.5 cm, 10 cm

Question 5

ASTM Code for Testing of Concrete Hollow Blocks (CHB) for Compressive Strength

Answer 5

ASTM C 140/14M -14

Question 6

Specimens Preparations

Answer 6

a. Sample selections from unit samples to ensure the results of the testing.
b. Samples for testing must the same configuration and dimensions.
c. Weigh the samples for testing.

Question 7

Testing Procedure:

Answer 7

a. Sample specimens age must be twenty eight (28} days.
b. Plates must be arranged on steel blocks in such a way that the center of the specimen coincide with
the centroid of the thrust block.
c. Proper capping of sulphur and granular materials coating or gypsum plaster on the bearing area of
the masonry units to maintain uniformity of the surface.
d. Maximum load is applied at a constant rate and the remaining load is applied in not less than two (2)
minutes on the masonry units in the machine.
e. Record compressive strength of the individual units and calculate the minimum average
compressive strength of the masonry units.

Question 8

Sample specimens age must be __ days.

Answer 8

28

Question 9

Maximum load is applied at a constant rate and the remaining load is applied in not less than __
minutes on the masonry units in the machine.

Answer 9

2