Quality checks is always an important part of Civil Er. daily job, and here we have some tips regarding the QUALITY CHECKS on AAC block masonry wall at site.
Check No. 1
 |
| Incorrect Method of Stacking |
In continuation to this, engineers should also have check
the all blocks should be regular placed in a correct manner not in an irregular
manner. These checks will not form the hair line cracks in blocks.
 |
| Correct Method of Stacking |
Check No. 2
Do not allow
to construct the AAC block masonry wall more than 900 – 1200 mm height in a day
to masons. After a defined height a RCC band or a layer of cement mortar with
nominal reinforcement is must to avoid the cracks.
RCC layer is also required
on the sills of windows to avoid the crack formation due to drill for windows
frame fixing purpose.
 |
| Height of AAC Block in a Day |
 |
| RCC Band on Sill of Window |
Check No. 3
All joints
in the block masonry wall should be staggered like in red brick masonry wall.
Staggered joints will help to distribute the load properly and uniformly, hence minimize the
chances of cracks.
 |
| Staggered Joints |
Check No. 4
The
thickness of joint should be 10-12 mm in case cement mortar, and if chemical or adhesive is being used in masonry then 3-4 mm thickness is allowable.
Excessive thickness of binding material in both the cases will be counted as a wastage of material and will be responsible for the formation of cracks as well.
Excessive thickness of binding material in both the cases will be counted as a wastage of material and will be responsible for the formation of cracks as well.
The ratio of
mortar needs to be cross - verified at site while the expiry date of adhesive should also be
a part of checklist.
 |
| 3-4mm Joints - AAC Block Adhesive |
Check No. 5
Engineers
must check the placing and position of the lintel on AAC blocks, it should be
placed from end to end or column to column otherwise cracks will be formed
because blocks cannot take much load. By placing like this will distribute the
load uniformly on the complete blocks.
 |
| Lintel Throughout the Length |
Check No. 6
Engineers
must check that the AAC block masonry top layer should not be directly come
under the contact of RCC beam. There is always should be resilient material
(cement mortar) in between them.
This material will act as a sandwich and will not transfer the stresses from beam to directly on the AAC blocks which is the actual reasons of cracks on the top layers.
This material will act as a sandwich and will not transfer the stresses from beam to directly on the AAC blocks which is the actual reasons of cracks on the top layers.
 |
| Cement Mortar Placed Below Beam |
Check No. 7
Like every
cemented material required curing, it is required here as well if cement mortar
is being used as a binding agent for AAC blocks. Water is to be spread on the face of cement mortar only, instead to wet the complete masonry wall.
Check No. 8
It is to be
checked that masons should have eligible tools to cut down the AAC blocks for
masonry purpose. Use of chisel and hammer should be strictly prohibited at site
for cutting the AAC blocks and chasing work as well.
Cutters are recommended for laying conduits and plumbing pipe in walls.
Cutters are recommended for laying conduits and plumbing pipe in walls.
 |
| Chasing Through Cutter Machine |
 |
| Handsaw |
Check No. 9
Before to
start the plaster work, engineers must check the surface of the AAC block
masonry wall that the block masonry should not have any offset beyond the
tolerance limit, and wire mesh should be pasted on the joints of block and
concrete.
 |
| Surface of AAC Block Before Plaster |
Check No. 10
Although we
can use cement plaster on AAC block but it is my recommendation or experience
that the use of Gypsum plaster will be more advisable instead of cement plaster
in case to avoid cracks on surface later on.
The reason is both the materials almost match their expansion and contraction requirement.
The reason is both the materials almost match their expansion and contraction requirement.
1 Comments