Rammed Earth Construction Part 21210466806514

8/6/2019 Rammed Earth Construction Part 21210466806514

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CONSTRUCTION PROCESS



• The formwork is constantly removed and placed on the next set of horizontal timbers where the process is

repeated. Once the formwork has been moved on, the horizontal timbers are removed from the wall leavingcharacteristic holes. Upon completion of one horizontal level the formwork is moved vertically, the mass of standing

wall being known as a lift.

• The wall is so solid that, if desired, the forms can be removed immediately. This is necessary if wire brushing toreveal texture is desired otherwise walls become too hard to brush after around 60 minutes.

• Walls take some time to dry out completely, but this does not prevent further work on the project.



FORMWORK BRACING TECHNIQUES



DESIGN CONSIDERATIONS• Rammed earth walls have low tensile

strength, and should be reinforced by

providing a bond or collar beam.

• Beams can be constructed of concrete,

wood or steel.

• Vertical reinforcing may also be done,

and may be required by some building

officials.• All openings in rammed earth walls, such as

windows and doors, must have lintels to

span the opening width.

• Water flow and moisture control is

critical to protect structural walls. Special

detailing to accommodate manufactured

windows may be necessary to accommodate

wall thickness.

REINFORCEMENT PROPORTIONS



• All openings for doors and windows will require a frame.

Wood, as opposed to metal, is recommended due to the

corrosive action of moisture from the soil material.

• Careful attention to both roof and opening details is

necessary to protect the structure from water damage.

• Foundations required by most codes are concrete

reinforced with steel.

• Soil block material may be used as a filler material

between piers of a reinforced concrete pier and beam

foundation.• Historically, many structures built with earth materials had no

foundation, or used sand and gravel foundations. The

latter are excavated trenches filled with two parts sand to

three parts gravel. Trench bottoms were graded to providepositive drainage.

• Soil material block should not be used in below grade walls

unless supported on both sides. Natural moisture from the

ground may infiltrate the block, resulting in reduced

compressive strength.

OPENING PROPORTIONS



BAMBOO REINFORCED RAMMED EARTH• A Rammed earth wall is erected over a bamboo reinforced

monolithic stone foundation, using a special T-shaped steel slip

form.

• The 31 inch wide wall sections are rammed continuously until the

final wall height is reached so that no horizontal shrinkage cracks can

occur.• Each section is separated by a ¾ inch gap to provide for

independent movement during seismic activity.

• Four vertical bamboo rods act as

reinforcement for the wall sections, and togetherwith the gap give sufficient stability against

horizontal loads created by seismic activity.

• The bamboo is interconnected with the

reinforcement of the foundation as well as with the

ring beam that connects the tops of all the wall

sections.



BENEFITS OF RAMMED EARTH

• Reduced CO2 Emissions

• Thermal Mass

• Noise Reduction

• Strength

• Durability

• Low Maintenance

• Fire Resistance

• Pest Resistance

• Cost Effective

• Rapid Construction

• Environmentally Friendly



CO2 Emissions• Using rammed earth as a construction material

greatly reduces the amount of CO2 released during the

construction of the building.• The manufacture of cement requires the burning oflimestone and produces CO2 as a waste product.

• Around 10% of global CO2 emissions are from thecement industry.

• In using soil taken directly from the site, there is notransport requirement, directly reducing CO2emissions and taking vehicles off the road.

Thermal Performance• The high thermal mass of rammed earth walls mean they

act to naturally regulate the internaltemperature of a building.

• If a rammed earth wall is designed into the heatingsystem of a structure, the energy required to both heat

and cool the building can be greatly reduced, whichfurther reduces the CO2 emissions of the building.

• Rammed earth naturally regulates the internalrelative humidity of the building, producing an

improved air quality.• This contrasts greatly with air conditioning systems,which act to dry the air in a building and contribute toharsh working and living environment.



Structural Performance• Rammed earth is perfectly able to act as

load bearing members within a

structural system.• The strength of dry,

un-stabilized rammed earth is

close to 1MPa.

• The strength and stiffness of

the material reduce greatlywith increasing watercontent, and thus the building must

be well designed in order tomaximize the structuralpotential of the rammed earth.



Feasibility• Rammed earth complies

with Building Regulations

for insulation,strength, waterresistance, fire andacoustics.

• Not all soils are suitablefor use as rammed earth.The soil must becompacted at a particular

Embodied Energy

• The inherent recycle-ablilityof rammed earth, and thereduction in CO2 emissions duringthe lifetime of the structure, thehigh thermal mass and thus lowoperating costs all mean thatrammed earth has a much lower

embodied energy than comparablebuilding materials.

water content to

ensure optimumcompaction, and thiswater content should bepredetermined beforeconstruction begins.

• Structural design oframmed earth buildings isusually very simple, with

walls acting incompression, but

detailing is important toensure the rammed earthis used to its maximumpotential.



GREEN BUILDINGSVineyard ResidenceVictoria, Australia• Architect: John Wardle Architects

• Completion: 2002• Area: 400 m2

• Rammed Earth Walls angling outward evokes

the impression of continuing into the landscape.

• Cross ventilation is achieved throughout all theareas, between the walls.





Center for Gravity Foundation Hall

Jemez Springs, New Mexico

• Architects: H. Predock, J. Frane• Completion: 2003

• Area: 279 m2

• The thick Rammed Earth Walls act as thermal

composites, keeping unwanted summer heat out during

the day and re-radiating it at night.

• Cooling is achieved thru cross ventilation by opening the

sliding panels to the east and the entry doors to the west.

• In the winter, heat is generated by geothermal water.





Chapel of Reconciliation

Berlin, Germany

• Architect: Reitermann + Sassenroth• Completion: 2000

• Area: 315 m2

• The interior is of oval shape, and is

delimited by a rammed earth wall 7.2min height and .6m in thickness.

• The Rammed Earth wall contains large

fragments of broken brick from the

former church, as well as gravel, whichtogether constitutes 55% of the

material. This coarse-grained

mixture reduces material

shrinkage to only .15%.• The admixture of flax fibers and

intensive compaction with a tamping

roller was able to produce a

compressive strength of

3.2N/mm2.



Documents

Rammed Earth Construction Part 21210466806514