Do you know the advantages and disadvantages of steel structures?
The advantages of steel structures
(1) the advantages of light weight compared with the traditional reinforced concrete structure, steel structures has the characteristics such as high strength, light weight, its weight is only 1/5 of the brick structure, resistant to 70 meters per second, typhoon, protecting the personal and property safety.
(2) good aseismic steel structures using the stability better "rib plate structure system", it has a very strong seismic performance, able to resist earthquake of magnitude 8.
(3) good durability of this kind of steel structure of the building is to use a combination of cold-formed thin-walled steel members, is the use of hot rolled galvanized sheet steel, so it can prevent steel rust, prolong service life of the building, service life can reach more than 50 years.
(4) steel structures is usually used in large span structure of large span steel structures, so that we can avoid to use columns, achieve the purpose of saving space.
(5) simple structure, economical steel structures is very light weight and cost is the 1/3 of the general structure, if the reinforced concrete structure: 800-1500 yuan/square meters; Steel structures: 260-500 yuan per square meter. This can effectively save costs.
(6) high flexibility steel structures USES is larger space design, interior space can be flexible segmentation, meet the needs of different users.
(7) heat preservation, heat insulation performance is good for thermal insulation sandwich board is used to, so can effectively stop the heat transfer, such as: 10 cm of R15 value sandwich board is equivalent to 1 m thick m2-m24 brick wall. In addition, its heat insulation effect can reach 60 decibels, which is two-thirds that of concrete and twice that of wooden structures.
(8) applied for steel structures high efficiency and energy saving system, the comfortable sex don't have to worry about formaldehyde, in addition, the house is set external ventilation, to ensure roof external drafty and heat dissipation.
(9) high productive all dry construction, steel structures is not affected by environment, season. A 2,000-square-meter building can have its main structure completed by just 10 workers in 30 working days.
(10) green environmental protection, steel structures high efficiency and energy saving can be 100% recycled materials, green without purification. In addition, all of them adopt high-efficiency energy-saving frames, so they can save about 50% of energy.
Disadvantages of steel structure
(1) no refractory temperature below 150 degrees, steel won't have what change, when the temperature in the 300-400 degrees, the steel structures strength and elastic began to fall, when the temperature at 600 degrees, the strength of steel is almost zero, so in special buildings, need to use refractory materials to improve the fire resistance of steel.
(2) the poor corrosion resistance in more water or corrosive substances more placest, steel strucures is easy to rust, so need regular cleaning and maintenance.
(3) shall not change the structure of the steel structures building, not to change the structure, because of its various components are linked together, to change will cause potential safety hazard.
What items need to be inspected for steel structures?
(1) nondestructive testing, ultrasonic testing, radiographic testing, magnetic particle testing, penetrant inspection. Performance test
(2) mechanical testing of steel, fasteners and mechanical test.
(3) the metallographic analysis, microstructure analysis, microhardness test, etc.
(4) chemical composition of the steel structures used by the steel chemical composition analysis.
(5) coating detection: surface coating for steel structures used in the paint for testing.
(6) stress test: in the process of the steel structures installation and unloading stress testing and monitoring of the key positions.