Concrete Canvas

by Sean Koeting

Created by: Peter Brewin and Will Crawford

CCO1 is an multi-award winning project that is soon to revolutionize the work of aid agencies and troops that help save lives in emergency situations. With over 35 million refugees worldwide, concrete canvas - 'the building in a bag' - will provide quick accommodation, field offices and medical clinics that give much better protection in extreme climatic conditions, better security against looting and enable otherwise impossible medical procedures. Unlike current solutions (soft- skinned tents), which offer inadequate protection, or are expensive and difficult to transport, concrete canvas is a rapidly deployable hardened shelter that requires only water and air for construction. It can be deployed by a person in under 40 minutes and is ready to use within 2 hours. Plus, with a design life of over 10 years, (tents only survive for 2 years) concrete canvas is a solution that saves effort and costs over the lifetime of medium to long term operations.

How it works...

Delivery - CC01 comes delivered folded in a sealed plastic sack. the dry weight is 30kg, an 8 man lift, and light enough to be transported on a pick-up truck or light aircraft. The pack contains a cement impregnated fabric (concrete cloth) bonded to the outer surface of an inflatable plastic inner.

Hydration - The sack is positioned and filled with water. The volume of the sack controls the water : cement ratio eliminating water measurement. the bag is then left for 15 minutes while the cement hydrates, this is aided by the fiber matrix which wicks water into the cement. Once hydrated, the sack is cut along its seams it then forms part of the ground sheet. Deployment is done at dusk to avoid over drying the cement.

Inflation - The key to concrete canvas is the use of inflation to create a surface that is optimized for compressive loading. this allows thin walled concrete structures to be formed which are both robust and lightweight. The structure is unfolded to form the shelter’s footprint. A chemical pack is activated which releases a controlled volume of gas into the plastic inner and inflates the structure. It forms a 'nissen-hut' shaped structure with over 16 m² of floor space and the technology can be scaled to provide larger structures.

Setting - The concrete cloth cures in the shape of the inflated inner and twelve hours later the structure is ready to use. Doors and ventilation holes are left with no concrete cloth bonded to the plastic skin this allows access points to be easily cut from the inner once the cement has dried.