During this year this site is closing down. So, if interested download Pictures and Documents, referring source.
Cette année il y aura la clôture de ce site www. Donc, profitez-en pour télécharger les photos et les documents qui vous intéressent, en citant la source.
Ingemar Saevfors
ingemar@saevfors.se
Kallangsvag 73, 18144 Lidingo, Sweden +46 703936761 www.saevfors.se
Architect/Urban planner with longtime lnks to Africa, the Americas and SE Asia, specializes in innovative building technologies for low income regions.
IN FOCUS NOW: The daunting perspective of housing another three billion people until 2050 is now further exacerbated by the fast climate change.
Construction News:
Bamboo based roof materials for cost savings and CO2 sink
Roof trusses and purlins are normally quite expensive items requiring high-end timber or metal profiles to meet the structural reliability. These components can easily be replaced by low-cost bamboo elements with their high tensile capacity, trimmed to a dimensional standard and combined with an efficient back-to-back gusset joint design.
Roof cover to replace the rusting corrugated sheet, which turns this metal roof into a hot bake oven.
A bamboo mat coated with a thin asphalt layer makes a waterproof roof cover that can be rolled out over the ridge.On top of the sticky asphalt, a thin layer of white sand is spread to protect against the sun.
A comparative cost analysis is underway. Comments are welcome!
If you can, replace the asphalt with locally grown natural rubber! It just needs vulcanizing to become a rainproof, fossil-free layer. Details: Asphalt+Bamboo Rolled_out_Roof.pdf Explanatory Youtube: https://www.youtube.com/watch?v=xu4vKvVoXW4
Agri-Voltaics: 
An intensified focusing on solar energy is now world-wide. However, solar panel parks of the quantities needed will demand enormous space on fairly flat land. The challenge will then be to sacrifice farm-land for a constantly growing world population. However, recent progress with transparent solar panels can also be combined with agriculture. Large structures supporting the transparent solar panels may permit sufficient light for farming below. Some crops can even have a certain advantage by the protection from scorching sun and violent down-pours of tropical rains.
A totally planar surface is important for solar panels. Such support structures, often in form of space frames, are today mostly made from aluminium profiles, often more expensive than the solar panels they support. The same structures could actually be made from bamboo, a local material made resistant to insects by low-toxic borax treatment. The cost difference compared to aluminium is gigantic. In addition, the benefits for rural livelihoods are obvious.
A pilot project is now under planning where the feasibility and cost consequence could be explored. Space frame structures of 16 x 16 m will be built allowing 4 m gaps for drainage/irrigation canals and access paths in between. Such a single unit 16x16 could already be instrumental to an evaluation of the concept.
More details...SolarPanelFixture
Solar panel fixture to PetCrown, bamboo space frame connector.
Stress analysis by KTH (Royal Institute of Technology, Stockholm) of the bamboo poles, considering upwind wind effects of 30 m/s, indicates a max axial compression force of 9.8 kN. (Corresponding to 14.3 MPa, much below allowable limit.)
