![]() ![]() The lower strength and weight of softwoods compared to hardwoods is due to the greater percentage of void space within the tree cells. In softwoods the cells, also referred to as tracheids, are longer than in hardwoods. There are longitudinal pores that carry water through the tree. Diameters are usually 0.1mm and lengths are usually 1mm. In hardwoods the elongated cells are relatively short. The strength of timber is also dependent on the amount of moisture in the wood. Softwoods have a simpler basic structure than do hardwoods because they have only two cell. The differences in properties of wood can be mainly accounted for by their varying densities. The hydroxyl groups of the hemicellulose capture water molecules through hydrogen bonds that affect the NMR relaxation times of the cell wall reservoir (T 1,1 and T 2,2), which allow discrimination between softwood and hardwood. are derived but they also differ in terms of their component cells. Middle wall (microfibrils orientated almost parallel to cell axis, also thickest layer)Īll of the common timbers used for building applications have very similar cell structures and compositions. The main differences between hardwoods and softwoods are botanical, and relate to the way the tree grows.Outer wall (microfibrils oriented in 2 directions not parallel to cell axis).Primary wall (randomly orientated microfibrils) Difference between hardwoods, softwoods and modified timber The trees of hardwood have usually broad leaves while the softwood trees have needles and cones for.The wood cell structure is set out below. ![]()
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