Social, economic and environmental dividends out of eliminating global deforestation and a fifth of climate change gases
By adding value to a most abundant, renewable but largely wasted natural resource, environmentally sustainable wealth is created. This resource is small diameter timber (SDT) which represents over 90% of all wood fiber in nature.
The LPSA (light prestressed segmented arch) is a breakthrough technology. It spans the intellectual gap between pre-computer linear theory in timber engineering and modern advances in non-linear continuum and computational mechanics. It is an application of PhD research work by this Institute’s founder, Ibrahim Al-Khattat, at Stanford University.
A simple slide-fit jointing method replaces the futile carpentry-based jointing procedures. Result is low-cost, low-tech mass utilization of SDT as a superior alternative to commercial mature timber. Humanity may then stop destroying the forests and their irreplaceable ecosystems—profitably. End products are bridge and building structures inherently resistant to the actions of earthquakes, hurricanes and flooding.
This is the engineering solution of the SDT jointing and analysis problem:-
thru a combination of elementary physics and advanced non-linear continuum and computational mechanics.
A 3-year old volunteer (above, left and center) slide-fits a SDT post into a bridge connector socket. A 20m LPSA bridge (above, right) assembled by school children in Iowa. In both cases, a tensioning system converts the assembly into a very durable structure that is amenable to advanced analysis and performance prediction. SDT ends are not damaged by slicing or bolting as in embedding methods.
This site has been
online since: Jan 22, 1997
Last update: Mar 05, 2019
The following are the carpentry techniques for SDT jointing used by the World’s experts. They render impossible any meaningful engineering analysis:
All of the following expert entities are aware of the LPSA technology. None of them has been able to challenge it, so they simply ignore it. Their own carpentry solutions (below) are devoid of any engineering analysis element or commercial viability.
· An European-funded consortium from: Austria, Finland, France, the Netherlands and UK. Their final report (1999) is at: www.vtt.fi/inf/pdf/publications/1999/P383.pdf
· The Forest Products Laboratory, USA. See: www.fpl.fs.fed.us/research/units/fpmu/small_diameter_roundwood.shtml
· TRADA, UK (Timber R&D Association): www.forestry.gov.uk/pdf/crwoodproducts27.pdf/$FILE/crwoodproducts27.pdf