Abstract: composites have many significant advantages in the application of construction engineering. For example, they can obtain high-precision complex shapes, have good resistance to degradation, and have strong corrosion resistance.
Composite materials have excellent properties such as light weight, high strength, corrosion resistance, water resistance, heat insulation and electrical insulation, and are widely used in the construction industry. They are energy-saving high-quality engineering materials. This book introduces the performance, design, manufacture and application of composite building structures. The book is divided into nine chapters, which respectively introduce composite roof structure, composite wall structure, composite load-bearing structure, composite floor and floor, composite inflatable structure, composite doors and windows, special composite building and reinforced polymer concrete structure.
1. Inorganic and organic materials
Glass fiber reinforced plastics, polymer concrete, asphalt concrete, etc.
2. Non metallic and metallic materials
Reinforced concrete, steel wire mesh cement, plastic aluminum composite pipe, aluminum foil faced linoleum, etc.
3. Other composites
Cement asbestos products, stainless steel clad steel plate, etc.
(1) High specific strength and high specific modulus. The outstanding advantages of composite materials are high specific strength and modulus. For example, the specific modulus of carbon fiber reinforced resin composites is five times higher than that of steel and aluminum alloy, and the specific strength is also more than three times higher than that of steel and aluminum alloy.
(2) High fatigue resistance. Fiber composites, especially resin-based composites, are less sensitive to notch and stress concentration, and the interface between fiber and matrix can blunt or change the direction of the crack tip, that is, prevent the crack from expanding rapidly, so the fatigue strength is relatively high. The fatigue limit of carbon fiber unsaturated polyester resin composites can reach 70%~80% of its tensile strength, while that of metal materials is only 40%~50%.
(3) Strong fracture resistance. There are a large number of independent fibers in composite materials, usually thousands to tens of thousands of fibers per square centimeter, which are combined into a whole by a matrix with toughness. When a few fibers are broken due to overload or other reasons, the load will be redistributed to other unbroken fibers, so that the components will not be suddenly damaged in a short time. Therefore, the composite materials have relatively high fracture toughness.
(4) Good damping performance. The natural frequency of the structure is related to the quality and shape of the structure itself, and is proportional to the square root of the specific modulus of the material. If the natural frequency of the material is high, it can avoid the resonance and the early damage caused by it in the working state.
(5) Good high-temperature performance and strong creep resistance. Because fiber materials can still maintain high strength at high temperature, the heat resistance of fiber-reinforced composites, such as carbon fiber-reinforced resin composites, is obviously higher than that of resin matrix. However, metal matrix composites show its superiority in heat resistance. For example, the strength of aluminum alloy decreases rapidly with the increase of temperature, while Shi Ying glass reinforced aluminum matrix composites can maintain 40% of room temperature strength at 500 C. The heat resistance of silicon carbide fiber, aluminum oxide fiber and ceramic composite in air can withstand 1200~1400°C, which is more than 100°C higher than that of all ultra-high temperature alloys.
(6) Good corrosion resistance. Many kinds of composite materials are resistant to acid and alkali corrosion, such as glass fiber reinforced phenolic resin composite materials, which can be used for a long time in acidic media containing chloride ions, and can be used to manufacture chemical pipelines, pumps, valves, containers, agitators and other equipment resistant to strong acids, salts, esters and some solvents.
(7) Excellent antifriction, wear resistance, self-lubrication and corrosion resistance. Composite components are suitable for integral molding because of their simple manufacturing process and good technological performance. At the same time of manufacturing composite materials, products are obtained, thus reducing the number of parts, fasteners and joints, and saving raw materials and working hours.
1. The aesthetic
They offer new aesthetic possibilities because of their ability to shape complex, smooth and creative shapes, as well as their ability to integrate special surface treatments and various effects, including simulations of traditional materials.
2. Corrosion resistance
Composites do not oxidize or corrode. There are a number of polymer based systems that provide long-term endurance in most temperature and chemical environments. Compared with traditional building materials, properly designed composite components have a longer service life and minimal maintenance.
3. The light
Composite materials have higher resistivity than most materials used in similar applications, and these materials provide greater gravity than most metal alloys.
How long can composite Materials last? There is a duration reference of more than 50 years. Polymer matrix composites are relative to the materials they usually replace, such as concrete and steel
Iron and wood are relatively new, so their “life expectancy” has not been applied in many composites.
Composite materials can be realized in almost any shape: it may have complex structure; It may be large or small, structured, decorated, or even a combination of them. Composite materials enable architects and designers to try new concepts, from prototype to production.
In view of this flexibility, a single component of the composite materials can replace complex units that require many fixed elements, which are made of traditional materials such as wood, steel and aluminum.
6. Dimensional stability
Materials formed from FRP maintain their shape and function even under severe mechanical and environmental pressures.
7. Dielectric properties
Polymer matrix composite materials have excellent electrical insulation properties.
8. High service temperature
Components made of polymer matrix and suitable filler have very good performance in high temperature applications.
glass fiber + synthetic resin. Its strength is comparable to that of steel, but its stiffness is not as good as that of metal. It can be used as daylighting material, enclosure material and decoration materialSuch as transparent corrugated board, translucent hollow sandwich board, daylighting cover, various composite boards, doors and windows, relief, veneer, etc. it can also make bathtubs, pipes and various containers. Basketball racks and trash cans are made of FRP.
the concrete is not tensioned under compression, and the reinforcement can be tensioned. The thermal expansion and cold contraction coefficients of the two are close, so they are used as structural materials such as beams, plates and columns.
there are many kinds of cement fiber board. What GRC glass fiber reinforced cement board, TK board, cement + glass fiber and other materialsMaterial. Used as ceiling, partition wall and external hanging.
There are three different kinds of polymer concrete, such as polymer impregnated concrete. After the polymer infiltrates into the internal pores of the concrete, the compactness of the concrete is improved.
It can be used in special document projects requiring high strength and high durability, such as high-pressure gas transmission pipeline, high-pressure infusion pipe, high-pressure container, marine structure, atomic energy reactor and other projects.
According to the process principle, the steel inventory can be divided into the following categories:
Crystal pattern steel: natural pattern steel, Uzi steel/Uzi steel, meteorite (black gold), high-grade coarse grain steel and high-grade mature iron.
Cast steel: made from pig iron and “wrought iron”, made from cast steel and cast steel/wrought iron.
Rotary welding, rotary welding steel: by rotary welding embedded steel and rotary welding horse tooth clip steel composition.
More steel inlaid steel forged groove: Wolf bite blade.
A gallery of earth-clad steel applications and production by combustion technology.
Flower steel different carbon steel and “by iron folding amount, forging roll system”.
The surface materials are grinded and grinded with steel on the upper knife by abrasive processing, fruit color processing, sharpness and a variety of changes.
Damascus (Damascus) : Damascus layers of steel that are made by mechanical welding or processing are powdery shuts that are the best Damascus steels that are processed after Damascus is ground and ground.
Images can be produced by industrial fusion, welding and other processes.