320 likes | 553 Views
Solent University. Research for Oxfam, Sheltercentre and others. Background Small practical undergraduate projects that have arisen from questions posed at various sheltercentre meetings. Rammed Earth Blocks.
E N D
Solent University Research for Oxfam, Sheltercentre and others
BackgroundSmall practical undergraduate projects that have arisen from questions posed at various sheltercentre meetings.
Produce a block that is cheaper and easier to produce than concrete blocks or fired bricks A block that is environmentally sound and durable Use of minimal stabilisation (lime or cement) Objectives
Compressive strength is not an issue with rammed earth blocks.Weaker hand moulded blocks reach strengths of 2-4 N/mm2Durability is an issue. Stabilisation with cement or lime will significantly improve durability
UK clay for manufacturing bricks was used. Consisting of 65% fine grained clay-like material with similar properties to lateritic tropical soils. Stabilisation: 1:20 5% cement 1:12 8% lime These are minimal. Typical recommended figures suggest 12 – 18% in which case perhaps concrete blocks would be better? Earth and stabilisation
No standards or best practice to date • Research into cold climate tents, but….. • Current flooring solutions proving inadequate
Develop and trial a simple and easily replicable testing procedure • Produce a comparative league table of material compositions for use in a cold climate emergency insulated floor
Materials & Testing • Waterproof bottom layer of plastic sheet • Robust and thermally effective layer of material • Layer of plastic sheet to separate materials • Insulating layer • Upper surface of plastic sheeting for living space Insulating Layer 10 Kg Sub-base Layer Frozen Ground = Layer of Plastic Sheet
The results indicated that Reflex is considerably stronger than the older form Monarflex plastic sheet. The most effective fixings were the large 25mm steel washer and the large plastic eyelet. However,a 50mm round stone wrapped in plastic sheet and tied round with guy rope proved to be the strongest fixing!
Reinforcing concrete with indigenous and waste materials found in the field
Replacing mild steel reinforcement in concrete, with indigenous, waste materials in non-load bearing, non structural concrete structures, such as water tanks, water wells, lintels, latrine slabs etc.
Strongest Weakest
The testing involved two primary and measured stages with a third further research stage. The first stage was to complete a pilot test in order to establish the correct field adaptation of the “Geelong test” (New Zealand Standard NZS4297/NZS4298)
A – Test Bed. B – Rammed Earth Block. C – Drip Generator. D – Water Hopper.
Engine oil and unfinished after erosion.Plain Lime Cement