Timber has been one of the primary materials of engineering construction; it is widely used for structural purpose. The engineering should have some knowledge of the classification of trees and of their growth and structure in orders to understand the fundamentals of the physical and mechanical properties of timbers. Classification of Trees For the engineering purposes, trees are classified according to their mode of growth:
a) Endogenous.
b) Exogenous.
c) Soft woods.
d) Hard woods.
a. Endogenous trees: This group is confined largely to tropical semitropical regions. Timber from these trees has very limited engineering applications. Example of endogenous tress is:
- Palms: because of their long, straight stems are sometimes locally used as piles.
- Bamboo: Is used structurally to a considerable extent.
b. Exogenous trees: These trees increase in bulk growing outer bark and annual rings are formed in the horizontal section of such a tree. Timber, which is mostly used for engineering purpose, belongs to this category. This timber can be divided into two groups: Soft woods: Such as deodar Hard woods: such as oak and teak.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
الرجوع الى لوحة التحكم
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