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Facility Design
 
The Air Manis Training Center will incorporate many features and technologies that are both simple and low cost. Strength and functionality through appropriate design will minimize the need for manufactured material. The building will also serve to demonstrate these technologies to NGO's and community leaders in such a way that it stimulates discussion of the issues it is designed to help address. Design criteria include:
Use of local renewable materials and existing skills
Tsunami refuge capacity - floating structure
Fast to erect and easy to supply in knock-down kit of parts
Good insulation in roof and sound deadening against rain
Expandable modular design
Low cost.
Training & Assembly Centers
A cable braced bamboo structure will be built to provide a sheltered boat building work area and an elevated office and administration space. The structure will be designed to withstand a mega quake and a moderate scale tsunami (3-4m) and to become a floating platform should a larger tsunami be experienced. This structure is low cost and can be relocated should that ever prove necessary. It can also be replicated and components pre-cut and supplied to remote locations as a multipurpose shelter and tsunami refuge combined. Regardless of the actual risk of further tsunamis in the region, the security of working in a quake proof structure that can also double as a tsunami refuge will help communities to overcome the long term effects of trauma and loss of family and friends.

If the Air Manis TC is no longer required, the building can be used for a fish market, net repairs, fisher association headquarters or as a community center for sports and youth activities as deemed best by the local residents. Replicas of this building in remote villages could also be used for temporary schools or aid distribution points. The proposed buildings are far more durable than tents and more comfortable.

The AM Training center will be built on a masonry / earth-bag base that will both elevate the structure and provide good security. The side walls will be designed to shear under severe tsunami impact and they are independent of the rest of the structure.  
'Tsunami Ark'  - A Bamboo Raft Refuge
The masonry ground level core will be reinforced and shaped like a ships bow to deflect debris away from the bamboo legs. The cable anchors will offer very little resistance to water and the roofing material will be a light palm thatch. This material provides excellent insulation and it deadens the sound of rain. It 'ventilates' in strong winds reducing uplift. The palm thatch will also lift and ventilate if submerged in a tsunami. It is not very durable when laid at maximum spacing and is designed to be replaced every 2 years. The illustration below does not show the catenary curve in the cable supported  roof. We do have the option of trussing with bamboo to form a rigid roof and will take advise from our architects.

Regular re-roofing will provide work for local communities as the palms used are common in the target areas.  Cable anchor blocks will be sized to deal with local wind storm conditions but made small enough so that they will drag if a cable is struck by debris in a tsunami.

The entire structure is built using highly buoyant bamboo and in a catastrophic failure the bamboo center section will be designed to lift clear and float like a raft or bamboo 'ark'. The ends of these bamboos will be left sealed so that air is trapped in the node divided core. No attempt will be made to seal between the bamboo canes in the wall. The structure will stand a much better chance of survival if it is porous to the force of the breaking wave. The self draining raft like format will dampen the movements after impact and help to stop people from being washed out the end by the force of the water.

The anchor blocks will then act to slow the structure rather than to hold it against the force of the water. The roof fixed to the cables will float adding to stability and providing a large raft for survivors.

As water levels drop the remains of the roof structure combined with the anchors will help the structure upright. The legs tend to 'ground' the raft and so stop it from being dragged back out to sea. If it is dragged out to sea the structure should still have some part of the roof structure intact and plenty of material for shelter available to the survivors.

Water, medical and food supplies can be kept in sealed containers at the inland end of the top floor secured in a strong bamboo cage. A VHF radio and satellite phone will be part of the inventory for each of these structures and so they can be used for coordinating emergency response in their vicinity.



• The illustration does not show the glazing to the office/loft area on the third level. Extensive use of horizontal round bamboo in the floor & walls will enhance survivability in an extreme tsunami. The  top floor will be surrounded by walls of 75mm round bamboo bolted to the uprights and so forming a 28m x 4m 'hull'.

• The building is 'modular' and it can be expanded in the long axis if required. (see illustration below)

 • Diagonal cable bracing will keep movement to acceptable levels.

 • Glazing will be glass louvres in metal frames to reduce the risk of falling glass in an earthquake and to simplify transport.

 • Masonry or Sandbag Adobe core and walls are built without any fixed attachment to the structure. The center "core" is shaped like a ships bow facing the ocean with steps on the inland end. This will keep debris clear of the legs in a smaller tsunami.

 • Assembly centers can be constructed on the ground (without the masonry core) making a smaller and lower cost structure for remote villages.

 • The building will be oriented towards the ocean so that a tsunami will pass through it. End walls will be light weight bamboo framed and designed to break free and float.

 • Wood and bamboo will be dried in passive solar ovens made by cladding the lower sections of the cables with clear polycarbonate roofing material. Other sections can be covered by plastic tarps to store timber/bamboo once seasoned.

In Aceh we met a number of people who survived being rolled underwater inside automobiles and many who grabbed hold of floating debris and were washed several kilometers inland. This structure will give communities who have no means of escape a fighting chance of surviving a mega tsunami and a safe refuge from tsunamis up to 4-5m.  The building is designed to inspire donors and to bring comfort to flatland coastal communities who now live in fear and have no feasible plan to deal with future disasters.

These residents of Onolimbu Nias had all constructed tsunami escape rafts from scrap wood.
Every house had some kind of raft and the collective effort to make them was substantial.
This was the best built escape raft in the village and it only had 3 drums. Most had one or two.

The raft belonged to the Kepala Desa (village head) He had the most luxurious house in the
area and one of a few that survived the quakes. Everyone was living in tents or thatch shelters.  

Tsunamis arrive as a wall of churning debris that would destroy these flimsy structures and only
add to the dangerous debris in the water. The villagers asked us to reassure them that the rafts
were a good idea. We did not know what to say and we will never forget the desperation of this
swamp village. There are hundreds of communities along the coast facing a similar predicament.
Modular Design can be expanded in 4m sections (bamboo walls not shown below)
Worms-eye view of the Air Manis Training Center structure. This cross section shows the solid earth-bag core and outer walls. Floor will be stabilized earth topped with a bamboo reinforced concrete slab. The only steel in the structure will be the galvanized cables and bolts. The bamboo modules are linked at floors and walls to the 3rd level (above the roof) will be continuous large bamboo bolted to uprights with staggered joints. (not shown in this illustration)

copyright Island Aid 2006

Masonry walls can be made from concrete block, brick or recycled building rubble as appropriate. In remote locations where transport is expensive, sand/soil from the site will be mixed with a low percentage of cement in rice bag tubes will be used for walls eliminating the need for block moulds or skilled labor. Barbed wire is run between the bags and light gage reinforcing rod hammered through the bags as required. The walls are built dry then wet or exposed to rain to cure.
Rice bag material is manufactured in tube form and is low cost. The illustrations show PP bags but we are investigating local sources for Jute tube material . If the tube materials is purchased in roll form, a large quantity can be transported at low cost. Lengths as long as the wall section are then cut and rolled up like the sleave of a shirt. The free end is sewn or stapled closed. A PVC tube is inserted into the tube and a mix of local soil/sand and cement/fly ash or lime blended dry at about 5-10%.

The mix is then poured into the tube and the tube laid in a foundation trench. There is no mortar used between the tube layers. Instead galvanized barbed wire is laid in two strands between each layer. The first two layers use double the amount of cement. After that the mix is made with less cement. Each soil type requires some experimentation. Tube size can also be varied to give thicker stronger walls if required.

After walls are complete, they can be hosed down or simply left exposed to rain and humidity to cure in-situ. Roof structures can be built in bamboo or timber as appropriate.
Walls can curve and can incorporate timber framed windows and door openings or natural arch openings as needed. Walls can be plastered or left as-is depending on function and budget. Steel reinforcing rods can be hammered down to pin layers together in earthquake areas and any floor plan can be built. Designs that incorporate curved walls will be inherently stronger than those with rectangular layouts but both are possible.
Bag rolls are compact and can be rolled easily. The roll in this image is 1,800 m long and weighs only 180 kg. The bag material for one square meter of wall will weigh between 0.5 and 0.8kg. In Indonesia this material is readily available as it is used for rice & sugar bags. Jute bag material is also available.