Explanation

Wood is required to have strong durability, strong transverse pressure resistance (local) strength and strong nail holding force. It is used outdoors and is greatly affected by the climate. Under suitable conditions, it is conducive to decay and termite activity. Therefore, wood is required to have strong natural corrosion resistance and be easy to carry out anti-corrosion treatment. Under the impact of heavy load trains, the local transverse pressure is very large, so the transverse compressive (local) strength of wood is required to be large, but do not use log with twist grain. At the same time, wood is also required to have a mother of pearl property, and the elasticity of wood is used to reduce the impact of the rail. It is required that the wood should have a strong grip on the spike to keep the rail firmly fixed. In addition, the drilling requirements for turnout sleepers and bridge sleepers are not fixed, which is not a problem for them. Suitable tree species for making ordinary and turnouts include larch, masson pine, Yunnan pine, spruce, fir, hemlock, steal wood, birch, white green oak, red green oak, oak, red cone, hard leaf cone, maple, etc. Suitable tree species for making bridges include larch, Huashan pine, Simao pine, Gaoshan pine, Yunnan pine, spruce, fir, hemlock, red pine, etc. Poplar can also be used as a trial. For Yunnan pine and eucalyptus trees, attention should be paid to the presence of twisting patterns (i.e. oblique textures), and for maple incense, attention should be paid to the presence of decay.

Classification