UNIVERSIDAD NACIONAL DE INGENIERIASTRUCTURAL LABORATORY FULL SCALE TESTING DIVISIONCISMID

MASONRY CONSTRUCTION GUIDEMarch, 2004

Lima - PerúCISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

CONSTRUCTION OF MASONRY BUILDINGS WITH
APPROPRIATED TECHNOLOGIESJapanese Advisor Committee

Yokohama National University
Dr. Yutaka Yamasaki
Center for Better Living
Tsukuba Building Test Laboratory
Dr. Mikio Futaki

Ministry of Land Infrastructure and Transport
National Institute for Land, Infrastructure and Management
Mr. Takashi Kaminosono
Mr. Tetsuro Goto
Building Research Institute
Mr. Hiroto Kato
Dr. Koichi Kusunoki
Infrastructure Development Institute
Mr. Ryokichi Ebizuka
Mr. Satoshi Nomura

Peruvian Researchers Committee
Faculty of Civil Engineering Staff (CISMID/FIC/UNI)
Dr. Carlos ZavalaEng. Patricia Gibu
Eng. Claudia Honma
Eng. Oscar Anicama
Eng. Jorge GallardoEng. Leslie Chang
Bach. Eng. Guillermo Huaco
Mr. German Bautista
Mr. Larry Cardenas

CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

ACKNOWLEDGEMENTS
This Guide has been produced upon the basis of the skills and knowledge acquired
through the execution of the Construction Technology Development and Promotion
Program in semi-developed and developing countries, which is under the supervision of
the Ministry of Land, Infrastructure and Transport of Japan.
The program is aimed at introducing to and establishing in developing countries those
construction technologies developed by these countries with the adaptation of the stateof the art technologies that have been developed in Japan and bear the likely traditional
methodologies, after their effectiveness having been certified in the pilot construction
work in the local places, and also through its related experiments.
The execution of the program was entrusted to Infrastructure Development InstituteJapan (IDI) by the Ministry of Land, Infrastructure and Transport of Japan, and CISMID
compiled the guide with the financial and technological support extended from Japan. A
specially organised experts committee discussed and was involved in the technologicalassistance.
In Peru masonry building with clay brick and adobe is the likely used system in house
construction. Those houses suffered severe damages in the past when earthquakes hit
them due to insufficient structural resistance to seismic shocks and unsatisfactory
quality control of construction work and building materials.
Under the circumstances the program was planned to improve the situation. The projectis intended to contribute to the mitigation of earthquake damages by improving theearthquake-resisting capacity (seismic performance) of confined masonry construction.
Such improvement is to be achieved in a way that is easy to Peruvian people, whichbecomes possible through adequate selection of materials, devices in detail ofreinforcing steel and adequate construction and its control without effecting drasticchanges to the Peruvian conventional construction methods. Experiments for checking
the resisting forces of houses and walls will also be carried out by applying force to unit
walls and a real-size 2 story house constructed especially for the experiment. And local
engineers will profit by seeing and being involved in their construction process. Its
ultimate target is to disseminate such improved house construction methods widely
helped by the construction guide derived from the program.
This guide represents the accomplishments of the Construction Technology
Development and Promotion Program of Japan that can be expected to contribute a lot
to the improvement to seismic resistance of the houses in Peru.
I hereby express my heartfelt appreciation to the Ministry of Land, Infrastructure andTransport of Japan, and also to The Infrastructure Development Institute - Japan for
their contribution to the improvement of the construction methods of houses in Peru.
Dr. Carlos ZAVALA
Associate Professor
Universidad Nacional de Ingeniería
CISMID/FIC/UNI
Lima PeruCISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

INITIAL REMARK
Masonry houses with good structural performance may be constructed by appropriate
construction procedures, good structural detailing and good quality control. This guidehas been divided in fourteen sections following the construction procedure. Structuraldetailing and quality control are discussed between the Japanese Advisor Committee
and CISMID considering the Peruvian construction system and the Japanese concept
on structural detailing, such as anchorages of reinforcements, and quality control. This
guide should be used for two or single story house, because our experiment was
performed with a real size 2 story house.
Each section presents questions of how to execute the construction works and also
recommendations to assure the quality in the construction site. When an item is very
important signal with a small man appear and shows the recommendation in green color.
Also if crucial note appear, a signal of stop will appear showing in red color therecommendation. These kinds of recommendations must be follows if the quality wants
to be reach on the construction site.
We hope you enjoy the reading of this guide and also spread the knowledge andrecommendations among your colleagues. It will help to improve our construction
technology on masonry houses.

CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

CONTENTSTHE CONSTRUCTION OF A MASONRY HOUSE
1. Introduction ---------------------------------------------------------------------------------------- 1
2. Which materials we use? ----------------------------------------------------------------------- 1zCementz
Sand (fine aggregates: fine and thick sand)zCrushed Stone (thick aggregates)z
Sand & Gravel (natural mix of aggregates)
z
Water
z
Masonry unitszSteel ReinforcementzWood
3. Which elements are the parts of the structural system? --------------------------------- 3
4. Where are these elements and materials in a real house? ----------------------------- 4
5. How do you know if walls amount is enough? --------------------------------------------- 5z
Example of how to check wall density
6. What should I do before starting the construction? --------------------------------------- 9z
Preparing the groundz
Drawing the structure on the ground
7. How should I build the foundation? ---------------------------------------------------------- 10z
Site conditionszDigging of trenchzPrepare bottom of foundationz
Place the reinforcement of the columns for wallsz
Place the simple concrete in the foundationz
Detail example of foundation
8. How to build the over footing? ----------------------------------------------------------------- 12
9. How to build a wall? ----------------------------------------------------------------------------- 12zPreparation of the bricksz
Preparation of the mortarz
The construction processz
Additional Notes
10. How to set the confining columns to the wall? ------------------------------------------- 15z
Placing the formsz
Placing of concrete
11. How to tie the walls and Columns? -------------------------------------------------------- 16
12. How to build the slab and beams? --------------------------------------------------------- 17zPreparing the concrete for beams and slabzPlacing the concrete on beams and slab
13. How to finish the surface of the elements? ----------------------------------------------- 21
14. How to control the quality of materials? --------------------------------------------------- 22z
Obtain samples of fresh concrete?
z
Slump
z
Quality control of masonry
GLOSSARY ---------------------------------------------------------------------------------------------- 24z
Basic ConceptszMaterialsz
Tools and Equipment

CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

THE CONSTRUCTION OF A MASONRY HOUSE
1. Introduction
Clay brick masonry building is the most likely used type of structural system on
housing in Peru and South America. More than 43% of housing are built using thissystem. In last 2001 Atico (Southern Peru) quake housing build with masonry
experimented damage. Main reason of this damage is the non quality control on theconstruction and improper structural configuration. Building a house without following
the National Standards of Earthquake design, the Masonry design standard and thisMasonry Construction guide could produce damage on the house.

2. Which Materials we use?
zCement
Coming in bags of 42.5 kg. It must be protectedfrom humidity for not harden before its use. Storage
space should be insulate from soil humidity throughplastic sheets or wood stands.

zSand (fine aggregates: fine and thick sand)It will use on the mix with cement, stone and water.
Its mission is to reduce voids between stones. Sand
shouldn’t contain earth (soil), mica, salt, organic
filthy, odor, iron compounds, blackish appearance.
Don’t damp sand before use.
You can prove if sand is bad putting sandin a recipient with water. If too much soil
or dust is present, it will separate from themix.
zCrushed Stone (thick aggregates)
Stone should be crushed or angular (sharp).
Should be hard and compact. Stones easily
breakable are not good.

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologieszSand & Gravel (natural mix of aggregates)
Sand & Gravel is a natural mix of stone of different
sizes and thick sand. It is used to prepare concreteof low resistance or quality like run foundation,
over-footing, false floor.
zWater
Water shouldn’t contain filthy elements, should beclean, drinkable and fresh.

Do not use dirtywaterzMasonry units
They are clay bricks and lime-siliceous bricks.
Masonry units can be solid, hollow or tubular. To
consider solid section without holes must morethan 75% of the geometrical area. The minimum
compression stress of bricks is 50 kgf/cm2.

Do not use uncooked clay bricks or irregularbricks. Clay bricks which are so white mustnot be used.
zSteel Reinforcement
For confined reinforced concrete elements
corrugated bars of 9.15m length and diameters of
3/8” and 1/2” should be used. For stirrups or hoops
can be used flat bars of 1/4” diameter. For tying
reinforcement bars black wire n{16 is used.
To prevent oxidation storage of bars can be coverby plastic sheets of wood boards.
zWoodWood boards and braces are used as form (mold).
Forms should be dry and protected from water;otherwise it remains humid (wet), swells up andbecomes soft. It is used to apply a cover of oil(petroleum) in the surface of wood board before its
use as a form.

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

3. Which elements are part of the structural system ?
Reinforcementof RC frame
horizontal member

RC one-way
small beam

RC slabLight weightclay brick

LintelClay brick
unit
MortarReinforcementof RC frame
verticalmemberMasonrypanel

Stirrup

Horizontal (head) joint
Castellated
verticaledge

Vertical (head) joint
Unreinforced
concrete beam
G.

L.

Foundation

If soil conditions are not good,
like soft sand or flexible soil,
the over footing must haveminimum steel reinforcement .

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

4. Where are these elements and materials in a real house ?
Beam and slab (light block slab)
Confining column detailSteelreinforcementof column

Continuous (run) foundation
And over-footing(vertical extension of foundation
before layering of masonry units inorder to protect them from humidityof ground)

Detail of theConfined
Column in its
whole length.

Main structural element:
Masonry Bearing Walls(Masonry and its confining
Elements: beams and columns work jointly)

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

5.

How do you know if walls amount is enough?

Structural design project is necessary to compute the reinforce elements, confinement
elements, walls amount, footings and others.
A preliminary computation usually used in the design phase of the project is theprocedure known as wall density ratio. This procedure is very simple and consists infinding the ratio between walls area and story area. The ratio should be examined oneach floor. It should also be examined severally in the vertical direction and in thehorizontal direction. A wall whose length is under 30 cm. shouldn’t be counted because it
isn’t effective enough.
As a result value the ratio must be compare with a threshold value proposed by the
Peruvian committee of masonry standards, which are as follows:
Soil TypeS1
S2
S3

Zone-3
4%
4%
5%

Zone-2
3%
3%
4%

Zone-11%2%2%Here the minimum wall density ratio is presented as a percent and is given for each soil
type and each earthquake zone in Peru.
zExample of how to check wall density
As an example we will consider the two story masonry house experimented in
CISMID/FIC/UNI, during this project.
In the Figure on the next page the plan of each story is presented. We will developed thefirst story wall density requirement as example.
a) Check in the vertical direction on the 1st floor
Each wall is named with two nearest horizontal axis and is own vertical axis. Then eachwall is identified its length, which is length of the wall including confined columns and theeffective thickness of the wall (without finishing). We already know the area of the story is
51 m2, and the results of the computations are presented in the following table:
Block in
Side
Side
width
Side
side
side
side
width

Material
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry

Wall
AB1
B'C1
AB2
AA'3
CD'1
DD'3
D'E3
D'E2

L (m)

L(cm)
t (cm)e (cm)h (m)h(cm)
Awall(m2)150.00
15.00
13.00
2.50
250.00
0.20
50.00
15.00
13.00
2.50
250.000.07
250.00
25.00
23.00
2.50
250.00
0.58
70.00
15.00
13.00
2.50
250.000.09
270.00
15.00
13.00
2.50
250.00
0.35
80.00
15.00
13.00
2.50
250.00
0.10
80.00
15.00
13.00
2.50
250.000.10
120.00
25.00
23.00
2.50
250.000.28
㺌Awall=1.76 m2
If wall density is less than the minimum required, Ahouse(m2)=
51.00 m2
1.50
0.50
2.50
0.70
2.70
0.80
0.80
1.20

wall density can be increase increasing the
3.5% 㻠 4.0%
thickness of the wall or increasing stiffness Wall Density=
Failreplacing a masonry wall by a concrete wall.
From the results in the vertical direction we found a wall density ratio of 3.5% which is notenough for our requirement in zone 3 with soil type 2, who need a minimum of 4% ratio.
For this reason, if we build it in zone 3 with soil type 2, we need to increase the amount ofwalls in this direction or we need to replace one of the walls by a concrete shear wall.
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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

1st floor䎇䎉
Vertical direvtion

φHorizontal directionψ

2nd floort = wall thicknesse = effective thickness
h = height of wall
L = length of wall

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologiesb) Example of replacing by a concrete shear wall
In our example we take this last alternative and replace the wall D’E2 by a shear wall ofconcrete with the same dimensions. Because material is different, we must find theequivalent thickness in masonry wall for the concrete wall. Then the thickness of theconcrete wall is multiply by the ration Ec/Em (ratio between elastic modulus of theconcrete and elastic modulus of masonry) to make our computation.
Block in
Side
Side
width
Side
side
side
side
width

Material
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Concrete

Wall
AB1
B'C1
AB2
AA'3
CD'1
DD'3
D'E3
D'E2

L (m)

L(cm)
t (cm)e (cm)h (m)h(cm)
Awall(m2)150.00
15.00
13.00
2.50
250.00
0.20
50.00
15.00
13.00
2.50
250.000.07
250.00
25.00
23.00
2.50
250.00
0.58
70.00
15.00
13.00
2.50
250.000.09
270.00
15.00
13.00
2.50
250.00
0.35
80.00
15.00
13.00
2.50
250.00
0.10
80.00
15.00
13.00
2.50
250.000.10
120.0025.00
212.382.50
250.002.55
㺌Awall=4.03 m2
Ec=
217000 kg/cm2
Ahouse(m2)=
51.00 m2
Em=
23500 kg/cm2
Wall Density=
7.9% 㻠 4.0%
Concrete wall properties are transformed to
OK
1.50
0.50
2.50
0.70
2.70
0.80
0.80
1.20

masonry wall equivalence

Finally, replacing wall D’E2 by a concrete wall provides a wall density ratio of 7.9% value,
which is over the 4% required; this value will assure good behavior against quakes as
test results shown.
c) Check in the horizontal direction on the 1st floor
In similar way as on the vertical direction, walls are named with two nearest vertical axes
and it’s own horizontal axis. Then each wall is identified its length, which is length of thewall including confined columns and the effective thickness of the wall (without finishing).
The results of the computations are presented in the following table:
Block in
Side
Side
Side
Side
Side
Side
Side

Material
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry

Wall
12A
23A
12C
2'3C
2'3D
12D'
23E

L (m)
2.35
3.45
2.35
2.30
2.30
2.35
3.45

L(cm)
t (cm)e (cm)h (m)h(cm)
Awall(m2)235.00
15.00
13.00
2.50
250.000.31
345.00
15.00
13.00
2.50
250.000.45
235.00
15.00
13.00
2.50
250.000.31
230.00
15.00
13.00
2.50
250.000.30
230.00
15.00
13.00
2.50
250.000.30
235.00
15.00
13.00
2.50
250.000.31
345.00
15.00
13.00
2.50
250.000.45
2.41 m2
㺌Awall=Ahouse(m2)=
51.00 m2
Wall Density=

4.7% 㻠 4.0%
OK

The wall density in this direction is over the required 4%, and assures a good behavior of
the structural system.

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologiesd) Check in the vertical direction on the on the 2nd floor
In order to find the wall density ratio for this direction, we must consider the walls whocame from the lower level. It means, only the walls who start on the foundation are
consider for this computation. Therefore, amount of walls for this direction is the same as
the one on the first floor because wall BC3 is not consider. Then, if replacement of wallD’E2 remains on the second floor, wall density is computed in the following table:
Block in
Side
Side
width
Side
side
side
side
width

Material
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Concrete

Wall
AB1
B'C1
AB2
AA'3
CD'1
DD'3
D'E3
D'E2

L (m)
1.50
0.50
2.50
0.70
2.70
0.80
0.80
1.20

L(cm)
t (cm)e (cm)h (m)h(cm)
Awall(m2)150.00
15.00
13.00
5.00
500.00
0.20
50.00
15.00
13.00
5.00
500.000.07
250.00
25.00
23.00
5.00
500.00
0.58
70.00
15.00
13.00
5.00
500.000.09
270.00
15.00
13.00
5.00
500.00
0.35
80.00
15.00
13.00
5.00
500.00
0.10
80.00
15.00
13.00
5.00
500.000.10
120.0025.00
212.385.00
500.002.55
㺌Awall=4.03 m2
Ec=
217000 kg/cm2
Ahouse(m2)=
51.00 m2
Em=
23500 kg/cm2
Wall Density=
7.9% 㻠 4.0%
OKe) Check in the horizontal direction on the on the 2nd floor
In this direction wall 12D’ has an opening, and is divide into two: wall 11’D’ (before theopening) and 1’2D’ (after the wall). Therefore for this direction wall density become:Block in
Side
Side
Side
Side
Side
Side
Side
Side

Material
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry
Masonry

Wall
12A
23A
12C
2'3C
2'3D
11'D'
1'2D'
23E

L (m)
2.35
3.45
2.35
2.30
2.30
0.93
0.93
3.45

L(cm)
t (cm)e (cm)h (m)h(cm)
Awall(m2)235.00
15.00
13.00
5.00
500.000.31
345.00
15.00
13.00
5.00
500.000.45
235.00
15.00
13.00
5.00
500.000.31
230.00
15.00
13.00
5.00
500.000.30
230.00
15.00
13.00
5.00
500.00
0.30
93.00
15.00
13.00
5.00
500.00
0.12
93.00
15.00
13.00
5.00
500.000.12
345.00
15.00
13.00
5.00
500.000.45
2.35 m2
㺌Awall=Ahouse(m2)=
51.00 m2
Wall Density=

4.6% 㻠 4.0%
OK

Then, wall density shows a reduction in this direction but is enough to satisfied therequired minimum of 4%

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Construction of Masonry Buildings with appropriated technologies

6. What should I do before starting the construction?
zPreparing the ground
Ground should be clean, without rubbish neither organic material nor any odd element to
the ground.
zDrawing the structure on the groundRopes (cord) are tightened, using trestles made by wood poles nailed to a transversal
stick and embedded to the ground, as shown in the figure. Trestles are placed at externalpart of build. Check the angle of 90{ at the corners making triangle of 3-4-5 length sides,
as shown here.
Wall alignment90{ angle

Laying out

3

54
TrestlesLevel of the ground should beverified to know how are theunevenness. It can be used level,
theodolite or transparent hose level.
Trace of building axis and wallalignment or laying out should bemade using gypsum powder, chalk,or similar, marking the trenches forfoundation.

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

7. How should I build the foundation?
zSite conditions
The behavior of any foundation depends of the ground condition. Dense gravel,compact sand or silt or rigid clay are example of good ground. Foundations settled onthese soils are expected not to experience any problem.
However, if non-controlled landfill or garbage deposits compose the ground,large settlements are expected on the foundation. Therefore construction
on these kinds of soils is prohibited.
zDigging of trench
A trench digging for continuous foundation should
be made following the structural plans anddetails.
It is important that foundation to be leveled
below the ground level, on natural soil at a
depth not less than 1.0 m. If thickness ofthe shallow landfill is greater than 1.0 m
the trench should be over excavated until
it reach the natural soil and refilled withsimple concrete.
zPrepare bottom of foundation
Bottom of trench should be compacted andleveled. Foundation dimensions should consider
future expansion of the building like theincreasing of the stories, at the time of thedesign.
Use aCompact
Hammerto reachlevel

Level ofgroundBottom of trenchleveled andcompactedzPlace the reinforcement of the columns for walls
Reinforcement bars of columns -previously
assembled as a basket- are placed and fixed into
the foundation.
The basket of hoops must have enoughspace to let in concrete vibrator device
into the column

10

Hoops with hooks
at 135º angle.
The minimum
diameter of hoop
confinement is with
6 mm.

CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologieszPlace the simple concrete in the foundation
With reinforcement of all columns placed andprovisionally fixed, continuous foundation is filledwith simple concrete. For foundation the mix ofsimple concrete contains a cement-(sand-gravel)
ratio of 1:10 plus 30% of big stones. For the overfooting the cement-(sand-gravel) ratio for the mix
is 1:8 plus 30% of medium stones.
zDetail example of foundation

The upper Figure shows examples for good soil condition of likely used types offoundation:
Section A-A: 0.50x0.70m foundation for 15-cm thickness wall.
Section B-B: 0.60x0.70m foundation for confined column on 25-cm
thickness wall.
Section C-C: 0.60x1.10m foundation for staircase.
When soil condition is not good, increase of width or depth of the foundation is required.
Careshould
be
taken
when
transporting fresh concrete frommixer discharge to the trench, andalso in placing concrete in order tonot separate stones from fresh
concrete. A good curing should be
performed, allowing the concrete toreachenoughstrength,imperme-ability and durability. Lackof curing causes low resistance and it
could appear cracks due to thecontraction for drying of concrete.
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Construction of Masonry Buildings with appropriated technologies

8. How to build the over footing?
Over the run foundation continues theover-footing to be used as support for thewall. The main purpose is to isolate thewall from the soil and provides protection
against humidity. Here it is used woodboards as a form or mold the over footing.

If soil conditions are not good,
like soft sand or flexible soil,
the over footing must haveminimum steel reinforcement
to work as a foundation
connection beam.
It is recommended to use a mixture ratio of cement, sand and gravel for the over footingof 1:8 plus 30% of medium stones. Also vibrator or rods are required to reach a good
mixture.

9. How to build a wall?
To build the wall we must prepare the mortar and prepare the bricks before start
the process. Above the over-footing, it starts layering of brick units over mortar bed,
forming masonry walls.
zPreparation of the bricks
Bricks should be wet before layer them sothey don’t absorb water from mortar andobtaining a good adherence mortar-brickzPreparation of the mortar
To make the mortar, the mix will have thicksand - cement ratio of 5:1. Sand andcement should be mixed dry, out from thetray. Next this dry mix is put in the tray
mixing it with water.

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologieszThe construction process1  

CementThick sand
Water

2

To
make
the
mortar, sand andcement should bemixed dry, out fromthe tray. Next, thisdry mix is put in the
tray mixing themMasonry units (bricks)
Bricks should be wet before
layer them, so they don’t absorb
water from mortar, and obtaining
a good adherence mortar-brick3
4

Over mortar bed
placed the bricks.

are5

Using a palette or brick layer’s trowel
mortar are placed over bricks in a way
mortar penetrate bricks holes
6Each layer of brick,should be checkedvertically using a leadweight7

Bricks at lateral edges of wall will be the “master brick”.
With the help of a screed board and a cord fixed
between master bricks it is verified horizontal level andthe thick of mortar joint, which should be the same forall bricks in the layer.

The wall reaches its
final height

Verify the vertical level of the wall after
each layer. Do not build more than 1.2-m
height of wall per day.
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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologieszAdditional Notes

For the next layers this procedure isrepeated. It is important the thick of mortar
layer, if excceds1.5cm, resistant of resulting
wall will be lower.
To cut a brick unit, it is used the small pick(“picota”). The pointed edge is used to markand the opposite side is used to cut andclean the lateral surface of brick. Up to
1.50m high, worker can be stand andmaking the placing of bricks. Higher thanthis, it should be used scaffold where placematerials and tools.
.

Considering as example handmade bricks with dimensionsof 14x24x9, the bricks can be layered longitudinally (wallthick of 14cm), or layered transversally (thick of wall is 24cm).
Longitudinal layering

Transversal layering

When bricks are hand-made, there are variability inits size, obtaining a non uniform wall thick.
Wall shouldn’t be picked or broken to make pipe
installation inside. It should be left needed space tocontain water, drainage, or electric piping. It meansthat in the place projected to cross a pipe, it shouldbe left a space without brick, place the pipe andthen the space will be filled with concrete. Piping
should always run vertically, never diagonally.

The ratio between the product of wall length by its thickness in reinforced
walls and the area of the floor is named wall density ratio. For Housing on
flexible soil wall density ratio must be at least 5%. Under good soil condition
wall density must be at least 3.5 %.

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Construction of Masonry Buildings with appropriated technologies

10. How to set the confining columns to the wall?
Be sure the reinforcement bars of thecolumns and stirrups were placed andfixed properly at the stage of thefoundation.
Maximum distance between confiningcolumns in a 14cm thick wall is 3.50m andfor a 24cm thick wall is 5.00m. In bothsides of a wall an empty place for column
place when layering bricks edges of wallare “teething” (castled vertical edge)
making layers not aligned vertically at theedges of wall -as shown in photo -, andobtaining a better tying or anchorage
between column and wall.
zPlacing the forms
The forms are made from wood panels or steel plates. Bracing of the panels isneeded to assure stability of the form.

zPlacing of concrete
The concrete must be transport by the operator in clean cans and drop from the topof the column. The process must continue in order to assure uniformity of the mix
and avoid dry joints among it. Vibration of the poured mix is required.
When placing concrete a good vibration shouldbe perform (through the use of vibrator devices
if possible) in order to get a continuous element
without air pockets (vacuum bags), which
weakens wall resistance. For concrete withstrength resistance of 210kgf/cm2, the volume
proportioning of materials is 1 of cement, 2 ofstone and 2 of sand. The water cement ratio isaround 0.45. Amount of water can be varied
based on the test mixing because weather
conditions, temperature and other external
factors.
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Construction of Masonry Buildings with appropriated technologies

11. How to tie the walls and Columns?
At the upper part of walls and between columns are made thecollar beam, which distribute load from slab, supply
confinement and anchorage to the wall.
Collar beam is as wider as the wall thick and its height are thesame that slab thickness –but 17cm as a minimum-. Minimum
reinforcement bars are 4#3 bars with stirrups spacing each 25
cm. Concrete for beams and slab are placed together.

Slab reinforcements
should be anchored
to beams certainly.

Column reinforcements should
be anchored horizontally to thebeams with enough anchorage
length.

Beam reinforcements should
be anchored horizontally tothe transverse beams withenough anchorage length.

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

12. How to build the slab and beams?
zPreparation of Forms and Steel Reinforcement for beams and slab
For concrete element (columns, beams, stairway
and slab) reinforcement are corrugated bars of steel,cut in appropriate length. After finishing wallconstruction and with arrangement of beam
reinforcement, forms for slab are placed. The
anchorage and developing length of bars must be
considered and also the minimum covering for thebars (see Table bellow).

Minimum covering for concrete elements placed at site constructione (cm)
Description
Elements in contact with ground or exposed to weather
4
For diameters equal or smaller than 5/8 h
5For diameters more than 5/8 h
Elements placed above ground or in contact with sea water
7
Elements neither in contact with ground nor exposed to weather
Light slabs
2
Walls or shear walls
2
Beams and columns (measured to the stirrup or hoop)
4
Shells or folded thin slabs
2

If wood forms are used, wetting the plates prior theconcrete placing is recommended, which is a similar
procedure to wet bricks. It demands extremely carefor keeping the level of the forms. Only small
deformation of the plates due to concrete mix
pressure is allowed.
Splice length of steel bars should be checkedaccording with its diameter. Splice length should be
at least 20 times the diameter of bar

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Construction of Masonry Buildings with appropriated technologies

Levels of bottom boards of the form for slab and beams must be
checked, to assure the height of the story.

Before place the concrete on the slab verify the position of tubes forelectrical wires and devices. Also verify the position of the waterand sewage sanitary pipes.

If you are working in a high floor
use a electrical lift for transport theconcrete or use a ramp fortransportation using bogies.

Put wood panels over the slab toroute the flow of transit during theconcrete place process

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologieszPreparing the concrete for beams and slab
For concrete with strength resistance of 210kgf/cm2,
the volume proportioning of materials is 1 of
cement, 2 of stone and 2 of sand. The water
cement ratio is around 0.45. Amount of water canbe varied based on the test mixing because of
weather conditions, temperature and other external
factors. A mixer machine is recommended to use
for the mix of the concrete. Ingredients of the mix
are input on the machine in the following order: first
introduce ¼ of the water amount, then the stone
and the sand, mixing as well as possible, to finish
with the cement, to complete the ¾ of water at theend of the mix.
zPlacing the concrete on beams and slab
Prior to the placing of the concrete thesurface of the hollow bricks must be
wet with clean water to avoid theabsorption of the concrete’s water by
the blocks.
The placing of concrete starts with the slab
beams followed by 5cm depth of concrete overthe slab. During the placement of concrete forslab, thickness of concrete should be checked,
using properly a wood plug or wood rules (furring
strip) to screed up to required level by sectors.
A way to do this leveling is making separated
stripes of concrete with specified level and thenfilling the space between them–as shown in thephotos. This procedure is repeated side by sidesuccessively finishing the entire slab.
A wood stick is used to leveling the surface ofthe concrete according with the stripes that areused as guidance for the worker.

A good vibration process must be
produced to avoid voids in theconcrete. Vibrators or steel bars
could be used for vibration. If voids
or irregularities are appeared in theconcrete the resistance in theconcrete will decrease.

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Construction of Masonry Buildings with appropriated technologies

After placement of concrete, a wood plate or bricklayer’s trowel (plate) is used to level the surface
giving it a better finishing.

Slab should be cured immediately after concrete
start to harden (at initial setting) during 7 days atleast. The first day or first night of curing is themost important. Special attention should be paid
to thin slabs or any structural element exposed to
the weather. Forms of slab can be retired after 7
days after its placement. A covering of flat
bricks or a mud covering can be placed above
slab, in order to prevent the slab getting wet fromrain.

The forms must be leftduring at least a minimum
time to get the initial
hardening of the placed
concrete. The table shows
the minimum time in daysfor each kind of element.

Minimum number of days to put out
the forms afer get initial hardening
Element
Walls
Columns
Beam sides
Beam bottom:
Lenght less than 3 meters
Lenght betwen 3 to 6 meters
Lenght bigger than 6 meters
Slab bottom in one direction
Lenght less than 3 meters
Lenght between 3 to 6 meters
Lenght bigger than 6 meters

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Day
1.0
1.0
1.0
7.0
14.0
21.0
4.0
7.0
10.0

CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

13. How to finish the surface of the elements?

For finishing of wall and ceiling surface it is necessary
the use of scaffolds, so covering works with mortar
can be made at the entire height of elements. It starts
from the upper part and then run down to the lower
part. The mix in volume has a proportion of 1 of
cement to 3 of fine sand.

It is very important to keep the mortar
workable, so the proportion of mixture mustremain identically during the whole process.

In columns or concrete elements should be made small picking
in order to obtain a better adherence of the mortar to theelement. To check the level of surface are used metallic and/or
wood squares (angles).
After the surface finishing, metallic or wooden frames forwindows and doors could be installed.
Finished all the structural work, door and windows installing, walls and ceiling can be
painted. At first sanding process over the elements is performed in order to discoverirregularities. Then putty process to cover the imperfections must be done prior to theapplication of the base paint. Finally paint finishing is put over the walls.

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Construction of Masonry Buildings with appropriated technologies

14. How to control the quality of materials?
zObtain samples of fresh concrete
It is important to take samples of fresh concrete from the mixed concrete that is being
used in the building. After hardening, those samples should be tested (called
compression test) to check the quality and resistance of concrete.
In the following it is described the procedure to take a sample of fresh concrete.
- Take a part of fresh concrete that is being
placed.
- In a metallic cylinder –should be withstandard size- previously greased, put the
sample in three steps or layers. Each layer
should be compacted with a 60cm length and5/8” diameter bar, giving 25 strokes as
showed in the first photo below.

- Remove excess of concrete,
to level with cylinder upper
part, obtaining a even surface- Mark the cylinders to identify
the sample with project place,element
placed(column,beam, slab, etc.) and date ofplacing.
- Next day remove hardened
concrete from its cylinder form
and place it in water for curing.
Leave cylinder in water 7
days.

Compression resistance (strength) is given by the following expression:
Where P is the maximum force applied to thecylinder at the moment of failure, and A is thesection (area) of the cylinder
kgf/cm2

Compression test are carried out usually at 7
and 28 days from sampling.
Concrete strength depends on water-cement
relation and of the level of compacting of themixed concrete.
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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologieszSlumpThis test is also named cone Abrams test, prove the concrete mix workability used in the
project. For this purpose metallic cone with 30cm height, 20-cm.-bottom diameter and10cm top diameter is used. The way to put the mix in the cone is similar to the cylindricalsample. After concrete is put on the cone, it must be removed to measure the relative
settlement respect to the height of the cone.
For a workable mix the relative settlement must be between 3 to 4 inches.

zQuality control of masonrya) Compression test on piles
Piles of 4 bricks are prepared when walls are underconstruction. Through this test compression resistanceof masonry piles is found, where maximum stress isnamed f´m.
Each block is placed with a mortar joint of a thickness
less than 1.5 cm.
The cement -sand ratio of the mortar is the one used on
the construction site.

b) Diagonal tension test
The test determines the diagonal tension resistance ofthe masonry. The test simulates the behavior of themasonry under extreme shear actions where tension
appears in the diagonal direction of the element.
A square element with 1.20 m. of length is build with thebrick unit to be use in the construction.
The load is applied on the testing in diagonal direction
and load is increase under constant rate till collapse
occurs.

c) Compression test of Mortar
This test determines the compression resistance of theplace mortar for used to form masonry. Cubic samplesof 5cm side or cylindrical samples of 5cm diameter with10cm. height are used as testing. The test is performed
in a compression test machine after 28 days of
preparation of the sample.

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CISMID/FIC/UNI
Construction of Masonry Buildings with appropriated technologies

GLOSSARY
Basic Concepts
Beam = Structural element that supports loads in transversal direction to its axis andbehaves mainly by flexion. A confining beam transmit loads to the wall
Bearing wall = Wall designed and constructed in a way that can transmit horizontal andvertical loads from an upper to a lower level up to the foundation.
Column = Element of reinforced concrete designed and built to bear and transmit
horizontal and vertical loads to the foundation.
Confined Masonry = Masonry method consisting in walls reinforced with confining
concrete elements.
Confined Wall = Wall with reinforcement elements (beams, columns) on its four sides.
Confinement = Group of element of reinforcement of concrete (beams and columns)
with the function of prove resistance and deforming capacity (called “ductility”) to thebearing walls.
Foundation = Part of the building that transmit to the ground the loads and forces of theentire structure
Joint = Gap between elements of a structure in order to control contraction, expansion
and vibration and avoiding cracking in the building.
Laying out = When marking on the surface of the ground the position of walls and trenchalignment, using stakes and cords.
Slab = Structural element used as a floor or roof, usually horizontal and reinforced in one
direction
Wall density = The ratio between the product of wall length by its thickness in reinforced
walls and the area of he floor
Materials
Ciclopeous Concrete = Plain concrete, without steel reinforcement, made by“hormigon” and placing on it up to 30% in volume of stones of 10” size as maximum
Concrete = A mixing of cement paste, water, sand and crushed stone or gravel.
Masonry (Albañileria) = Material composed by brick or block units and joined by amortar to make a wall.
Mortar = A mix of agglomerate (cement), aggregates (sand and stone) and water in a
specific proportion. It is used to glue units of bricks
Sand + gravel (Hormigon) = A natural mix of aggregates: sand and stone of riverdeposits.
Tools and Equipment

Air or bubble level
Used to determine
the level difference
between two or morenear points

Brick layer’s trowel(Badilejo)
A metallic or woodplate or palette used
to spread mortar for
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Construction of Masonry Buildings with appropriated technologies

Cord
Thick thread used tolevel bricks between
layers.

Lead Weight
Used to determining
a vertical alignment.
It is composed by acylindrical form
weight made of lead,which is suspended
by a thread crossing
its center.

Pick
A kind of hammer
with one pointededge and anothercutting plane edge

Scaffold
Metallic or wood
structure that permit
to work in a heightplace

Screed Board(“Escantillon”)
A metallic or wood
ruler with spaces
marked to indicate
and guide each layerof brick-mortar joint.

Square or Angle
Can be metallic orwooden assembled
in a cross of 90º andmaintain its position
by anotherdiagonally strip

Strut Column
Reinforcement
element, horizontal
or vertical, its
function to provenstability andresistance to the wall
against load
perpendicular to thewall surface.

Theodolite
Survey equipment, it
is used to checklevels or angles(vertical or
horizontal) from apoint of reference.

Tray(“Batea”)
Container where mixof aggregates areplaced to make themortar.

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