3.1 General
The materials used in masonry construction shall be in accordance with Part 5 ‘Building Materials’ of the Code. Storage of materials shall be in accordance with good practice [6-4(1)].
3.2 Masonry Units
Masonry units used in construction shall conform to accepted standards [6-4(2)].
3.2.1 Masonry units may be of the following types:
a) Common burnt clay building bricks,
b) Burnt clay fly ash building bricks,
c) Pulverized fuel ash lime bricks,
d) Stones (in regular sized units),
e) Sand-lime bricks,
f) Concrete blocks (solid and hollow),
g) Lime based blocks,
h) Burnt clay hollow blocks,
j) Gypsum partition blocks,
k) Autoclaved cellular concrete blocks,
m) Stabilized soil blocks, and
n) Concrete stone masonry blocks. NOTES
1 Gypsum partition blocks are used only for construction of non-load bearing partition walls.
2 Use of other masonry units such as precast stone blocks, fly-ash-lime-gypsum bricks, stabilized soil blocks and other bricks/blocks not covered by the above specifications may also be permitted based on test results.
3.2.2 Masonry units that have been previously used shall not be reused in brickwork or blockwork construction, unless they have been thoroughly cleaned
and conform to this Section for similar new masonry units.
3.3 Mortar
Mortar for masonry shall conform to good practice [6-4(3)].
3.3.1 Minimum compressive strength for different grades of mortar on the basis of mix proportions as per 3.3.2 are given in Table 1.
| Sl No. | Grade of Mortar | Minimum Compressive Strength at 28 Days N/mm |
|---|---|---|
| (1) | (2) | (3) |
| i) | H1 | 10 |
| ii) | H2 | 6.0 |
| iii) | M1 | 5.0 |
| iv) | M2 | 3.0 |
| v) | M3 | 1.5 |
| vi) | L1 | 0.7 |
| vii) | L2 | 0.5 |
3.3.2 Mix proportions and compressive strengths of some of the commonly used mortars are given in Table 2.
3.4 Durability Criteria for Selection of Masonry Mortars
3.4.1 The selection of masonry mortars from durability considerations shall cover both the loading and exposure conditions of the masonry. The requirements for masonry mortar shall generally be as given in 3.4.2 to 3.4.6 (see also Table 1).
PART 6 STRUCTURAL DESIGN — SECTION 4 MASONRY
| Sl No. | Mix Proportions(By Mass) | Minimum Compressive Strength at 28 Days in N/mm (with Cement Compressive Strength at 28 Days, in N/mm , Between 33 and 43) | Minimum Compressive Strength of Cement : Sand Mortar at 28 Days in N/mm (with Cement Compressive Strength at 28 Days, in N/mm ≥ 43) | ||||