Structural Evaluation of Traditional Wooden Buildings; Development and Analysis of Patterns with Environment and Earthquake Considerations

Considering the importance of resistant and low-cost buildings in sustainable development while preserving the history and tradition, a research on 400 wooden structures in northern provinces of Iran was conducted. The results show that in different areas according to the pattern of dispersion of various species of wood, buildings can be catagorized. at altitudes above 400 meters, the oak timbers are used in beams, columns or ceilings. In the foothill areas of Gilan state, rare types of Cupressus Sempervirens trees are used in foundation. For beams and columns, timbers of stronger trees like Boxwood - Oak - Beech are used. In the walls and floors we find alder tree like Zelkova Carpinifolia which are highly resistant to weight, humidity and insects. Types of foundations, walls, and ceilings, have been structurally studied. With reference to the importance environmental issues and earthquake, the best and the most favorable light wooden pattern for a residential building is proposed. The model was subsequently retrofitted, restructured and optimized in the university workshop. The obtained results from structural software analysis indicate that this pattern has a suitable performance against earthquakes, owing to its lightweight and proper bracing. Also, due to the use of wood in foundations, beams, columns, roof and mud walls, it is the best structure in terms of the environmental considerations. This is added to its benefits of appropriate speed of construction and reduction of the construction costs in comparison to concrete and steel buildings. Overall, the results suggest a perfect pattern for ideal residential buildings in the area The suggested pattern also shows acceptable standards of acoustic and thermal insulation. Taking into account both economic and environmental consideration, the use of fast growing trees, pine wood (Abies, Noel) in beams and columns are suggested It is also possible that by combining the pine wood in composite and strengthened profiles the increased compressive resistance would allow the construction of multistorey structures.