What are the materials of building wood
First class of wood: Korean pine, cypress, yew, camphor, nanmu, rubbing wood, lattice wood, hard rosewood, mahogany, flower palm boxwood, red green gang, hickory, walnut, beech, neem, incense Pile, ash, catalpa, ironwood rosewood.
Second class of wood: yellow fir, fir, Fujian cypress, torreya, tulip, pear, oak, water green net, hemp oak, alpine oak mulberry, jujube, yellow polo, ash.
Third class of wood: larch, spruce, pine, hemlock, cypress, redbud, soft rosewood, locust, birch, chestnut, lotus, maple.
Fourth class of wood: sweetgum, alder, hackberry, sandalwood, silver birch, red school, white eucalyptus, paulownia.
Fifth class of wood: pseudo-alder, poplar, maple poplar, balsa, yellow tung, holly, cypress persimmon.
The main use of building wood
①In civil engineering, the building wood is often used as the corrugated wood of the concrete formwork, which can play the role of reinforcing the formwork.
②In terms of house decoration, building wood is often used as a wooden keel, and it plays a very important role in the decoration of floors.
③In the aspect of building construction, building wood was also used as a material for pillars in ancient times
④In the production of furniture, building wood is often used as the backbone of many furniture and plays a supporting role.
The selection method of building wood
①Weighing method by hand: You can weigh the weight of the wooden square by hand, and the one with more water must be heavier.
②Hand touch method: Put your hand on the top of the wooden square and feel its dampness.
③Nailing method: You can use long nails to try to drive into the wooden square. If it is easy to nail, it means that the wooden square is relatively dry, otherwise, the humidity is relatively high.
④Shaking method: You can shake the finished wooden square with force from one end. If the quality is unqualified, it is generally easy to split into two parts from the middle.
⑤Eye observation method: How many knots are there in a piece of wood from the beginning to the end. If the knots are colored, it will not work, and it will be easily broken during installation.
Factors affecting the quality of building wood
①Pests
In the process of storage, transportation and use, wood will be often affected by insect pests. The natural enemies of wood are termites, beetles, weevil and so on. If the protection of the wood is not enough, it will be damaged by these pests, thus affecting the quality of the engineered wood.
It is recommended that if it is an outdoor wooden square, it should be soaked with preservatives, the preservatives can penetrate into the fibers of the wooden squares, so that the wood turns green from the inside to the outside, anti-corrosion, and resists insects.
②Crack
Cracks in the wood are often referred to as splits, which are due to the formation of cracks between the fibers of the wood, which can degrade the rating of the wood.
③ decay
Under certain conditions, wood will be attacked by wood-rot fungi and bacteria, which will cause the color and structure of the wood to change, making it soft and brittle, showing porous, powdery or spongy. This is the performance of wood decay.
④Color
The discoloration of wood is mainly caused by chemical discoloration and fungal discoloration. Chemical color is the discoloration phenomenon caused by the interaction between wood and chemicals.
Fungal discoloration is the discoloration caused by the invasion of fungal organisms into the wood.
⑤ Deformation
The mainly due to the warping deformation and twisting deformation of the bow in the process of processing, drying and storage, and the deformed wood has a certain influence on the quality.