“ Wood is a traditional building material , as popular today as ever . Because wood is anisotropic , natural wooden beams work better as vertical posts ( where they are in compression ) than horizontal beams ( where they are in tension )”.
HOW STRONG THE WOOD IS ?
Physically , wood is strong and stiff but , compared to a material like steel , it ’ s also light and flexible . It has another interesting property too . Metals , plastics , and ceramics tend to have a fairly uniform inner structure and that makes them isotropic : they behave exactly the same way in all directions . Wood is different due to its annual-ring-and-grain structure . You can usually bend and snap a small , dead , tree branch with your bare hands , but you ’ ll find it almost impossible to stretch or compress the same branch if you try pulling or pushing it in the opposite direction . The same holds when you ’ re cutting wood . If you ’ ve ever chopped wood with an ax , you ’ ll know it splits really easily if you slice with the blade along the grain , but it ’ s much harder to chop the opposite way ( through the grain ). We say wood is anisotropic , which means a lump of wood has different properties in different directions .
WHAT WOOD LIKE ?
The inner structure of a tree makes wood what it is — what it looks like , how it behaves , and what we can use it for . There are actually hundreds of different species of trees , so making generalizations about something called “ wood ” isn ’ t always that helpful : balsa wood is different from oak , which isn ’ t quite the same as hazel , which is different again from walnut . Having said that , different types of wood have more in common with one another than with , say , metals , ceramics , and plastics .
3 . wood architecture