Beton Siklop

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FOUNDATION FOOTINGS

FOUNDATION FOOTINGS The purpose of the foundation footing is to receive the load from the walls and distribute it over the ground. The size of the footing depends on the weight of the building, how much weight the soil can support, and the type of material used. For a load bearing wall footing, it is not usually necessary to place the footing footin g deep. If the soil is the same type and is hard in all places it is possible to dig the footing trench as little as 20 cm deep. Of course, for soft wet soil with no drainage, piles (pillars pounded into the ground) will probably be necessary. Concrete Reinforced with Steel Footing A reinforced concrete footing is good especially in places with earthquakes. Make sure that the steel rod used is free of rust and is well covered with concrete: no pieces should be near the surface or  sticking out (except the vertical rebar, which will receive blocks). Cyclopean Concrete Footing

Cyclopean concrete.

Cyclopean concrete is concrete that uses large stones to minimize surface area and economize on cement. It is not always always necessary to use steel in the footing. Steel footings have a disadvantage; after many years the steel may rust, expand and cause the concrete to crack. Instead of a steel reinforced footing, a nonreinforced cyclopean concrete footing can be used. A cyclopean concrete footing will save both cement and steel. Because it is nonreinforced nonreinforce d it will be thicker (and possibly wider) than a reinforced concrete footing. Shown below are some examples of nonreinforced footings. It is not possible to mix large stones in concrete. The concrete and stones must be placed in layers. The large stones should not touch each other. You should select extra-large stones that are as big as the width of the footing to be placed every 60 cm: they will make the structure stable. Use concrete 1:3:5 (cement:sand:stone, ratio by weight). Use mixed stone sizes.

Pouring a cyclopean concrete footing. Notice the large stones being added.

FOUNDATION FOOTINGS

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EXAMPLES OF CYCLOPEAN CONCRETE FOUNDATIONS If a reinforced concrete foundation is used, cast vertical rebar in the footing. If you use a non-reinforced foundation, use all channel blocks in the first block layer and reinforce it with steel: this is a ring-beam. Tie the vertical rebar to the horizontal rebar. .25

(WATER PROOF PLASTER 3 BLOCKS HIGH ) (BLOCK)

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One-story building footing for soft drained soil.

VERTICAL REBAR IS TIED TO RING BEAM* SEE “VERTICAL REBAR ANCHORING”

RING BEAM*:  SMOOTH 9 MM REBAR

CHANNEL BLOCK (CONCRETE FLOOR)

CYCLOPEAN CONCRETE (PLASTIC FILM TO PREVENT THE WALL AND FLOOR FROM SUCKING WATER) (SAND FILL) .0 9

CONCRETE 5 CM SAND 5 CM .2 5

One-story building footing for hard soil with drainage.

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*A RING BEAM IS HORIZONTAL REBAR LAID IN CHANNEL BLOCKS COMPLETELY AROUND THE BUILDING

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One-story building footing for soft wet soil.

.2 2 .4 4

.5 2

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Two-story building footing for hard soil with drainage. Second floor is concrete.

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Two-story building footing for soft soil with drainage. Second floor is wood.

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Two-story building footing for soft wet soil. Second floor is wood.

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VERTICAL REBAR

VERTICAL REBAR VERTICAL REBAR PLACEMENT Place vertical rebar at the sides of door  openings and at corners and intersections.

Set out the rebar positions accurately. The rebar will be in line with the large holes in the blocks.

Notice the rebar for  the buttress in the long wall.

VERTICAL REBAR ANCHORING

 A building without a reinforced steel footing will use channel blocks as the first layer and tie in the vertical rebar.

15 cm

Cut rebar as high as you can put a block on it. Or, bend the steel over.

Weld

Bend and hook Ways to extend rebar  

Wire tie