Through the comparative analysis of high-rise buildings with different building materials on different floors, and the analysis made by many experts in China, Professor Chai Chang, chief engineer of the Architectural Research Institute of the Ministry of metallurgical industry, is designing the headquarters building of industrial and Commercial Bank of China (high-rise steel structure system), and Professor Li Guoqiang, vice president of Tongji University, is designing several high-rise steel structure buildings in ShanghaiOn the basis of practice, the comprehensive economic benefits of high-rise steel structure and reinforced concrete structure are compared in detail.The conclusions are as followsThe total cost of all high-rise building structures (including the cost of foundation treatment, basement and superstructure) is higher than that of reinforced concrete structure; however, due to the use of steel structure with high material strength, the cross-section of structural members is small, so the occupied building area is less, which will bring economic benefits due to the increase of using area; in addition, different structures are adopted Materials have a certain impact on the quantities and construction period of the foundation and the construction period of the upper structure. The construction period of the steel structure is obviously shortened, so that the building can be put into use earlier, shorten the loan repayment time, reduce the loan interest, and rent income can be increased in advance.For the latter two items, the higher the number of stories, the more obvious the advantage of steel structure. 

For high-rise buildings below 20 storeys, the comprehensive economic benefits of reinforced concrete structure are higher than that of steel concrete mixed structure, and the comprehensive economic benefits of pure steel structure are very low; the comprehensive economic benefits of using steel structure are slightly higher than that of reinforced concrete structure from 20 to 25 floors;The comprehensive economic benefit of steel structure is higher than that of reinforced concrete structure in 25-30 floors; when the building is above 30 floors, the comprehensive economic benefit of steel structure is significantly higher than that of reinforced concrete structure.See the table below:

In addition, steel structure has its own advantages1. In terms of quality, the construction of reinforced concrete structure is easy to cut corners, and the project quality is difficult to guarantee. Relatively speaking, the quality of steel-concrete mixed structure project can be guaranteed because most components are made in the factory.2. Steel structure has been favored by many structural engineers because of its good seismic performance and flexible Bay layout. Especially for high-rise buildings in earthquake area, steel structure scheme has gradually become the first choice of structural engineers;3. The advantages of steel structure building structure, such as light weight, saving foundation cost, standardized production and installation, and fast construction speed, have been paid attention by investors. They can quickly and accurately occupy business opportunities, extremely fast investment return and stable investment income make steel structure become the key to success; 

　　4The steel structure has become a very favorable chip to win Luban Prize because of the great use of building space, the saving of a large number of scaffolds and templates, and a good image of the construction site. At the same time, steel structure residential and commercial buildings have gradually become one of the hot choices of real estate developers;5. The energy-saving and green building concept of steel structure has been strongly supported and promoted by the government;6. Compared with reinforced concrete buildings, steel structure buildings can save about 2% ~ 6% of the use area, its structure weight is about half of the reinforced concrete structure, and its construction period is about one-third to one-half of the reinforced concrete structure. For general buildings, the structure cost increases no more than 200 yuan per square meter, but its comprehensive economic benefits are significantly higher than that of reinforced concrete7. In the cost of main structure, the cost of foundation accounts for 1 / 3 weak, the cost of doors and windows and wallboard and floor slab accounts for 1 / 3 weak, and the structure cost of upper steel structure only accounts for 1 / 3; in all the investment, the cost of main structure accounts for about 30%, and that of upper steel structure only accounts for 7 ~ 10%.Therefore, the difference in structure has little effect on the total investment of the whole building.The difference between steel structure and concrete structure only accounts for less than 3% of the total investment; 8. In general, the self weight of high-rise reinforced concrete buildings is about 1.5 ~ 2.0 T / m2, and that of high-rise steel structure buildings is about 0.5 ~ 1.0 T / m2, which can reduce transportation and hoisting costs and foundation cost by about 30%.In the high intensity earthquake area, if the self weight is reduced by half, it is equivalent to reducing the seismic fortification intensity by one degree; taking the seismic fortification intensity of degree 8 as an example, the steel structure is adopted for medium height buildings, the weight is reduced by about 1 / 3, the earthquake action can be reduced by 30 ~ 40%, and the load area per unit area on the foundation can also be reduced by more than 30%.It can be predicted that with the development of China’s economic construction and the improvement of the overall technical level of steel structures, the comprehensive economic benefits of high-rise buildings using steel structures will be more significant.If other advantages of steel structure in construction are considered at the same time, such as less impact of weather on construction period, higher quality and accuracy, less impact on surrounding environment, and structural performance advantages, steel structure will be more widely used in the field of high-rise buildings and play its unique advantages.