The Finite Element Analysis With The Wall Of The Reinforced Concrete Silo Strengthened By CFRP Under Stress

The reinforced concrete silo has a lot of advantages such as large capacity, small covering area, simple convenient construction, low maintenance cost and so on. So it is widely used for storage of bulk solid in coal industry, cement industry, chemical industry, electric power industry, logistics industry and so on.As a typical cylindrical thin shell structure, store materials inside it produce the vertical lateral pressure perpendicular to the silo wall and the friction along the silo wall. According to the theory of cylindrical shells, the vertical lateral pressure perpendicular to the silo wall produces the circular tensile stress in the wall while the friction produces the compressive stress in the wall.The circular tensile stress produces the vertical cracks in the wall of the reinforced concrete silo and reduce the durability of the reinforced concrete silo and it leads to accidents easily. And before the reinforced concrete silos design specification of China issued, there have been a number of silos built and put into use. At that time, the designers were lack of knowledge about the storage material load and temperature stress of the silos. Under the load, earthquake and environment corrosion factors, some of these silos have been seriously damaged.If they are not be restored quickly,collapsed and some accidents that endanger life and property safety will be occurred.The tradition method to strengthen the reinforced concrete silo is using jet fiber reinforced concrete and circumferential prestressing. Using Fiber Reinforced polymer (Fiber Reinforced Polymers, hereinafter referred to as the FRP) strengthen reinforced concrete silo is a new method of reinforcement. It uses colophony structural adhesive to paste the FRP on the damaged structure surface. It can work together witn the structure and improve the mechanical performance of the structure. But it is seldom studied and applied in the engineering at present. Compared with the traditional reinforcement method, there are many advantages of using FRP to strengthen the reinforced concrete silo, such as no damage to the original structure,high strengthening efficiency, convenient for construction,low cost of maintenance,low additional load higy quality assurance, better durability and so on. Because of many advantages,the engineering application prospect of using FRP to strengthen the reinforced concrete silo is promising and it is valuable and necessary to study it.1.Summarize the research and application status of the strengthening of the reinforced concrete structure with FRP.According to the reinforced concrete silos design specification of China, and the lateral pressure calculation formula of the silo stored material,check the strength of the reinforced concrete silo combined with a project example. Introduce the trait of FRP. According the related research of domestic and foreign scholars, introduce the basic theory of the strengthening of thin-walled cylindrical shell with FRP, and establish the basic equation that FRP strengthen cylindrical shells structure based on the vertical pressure and internal pressure effect.2.Regarding the carbon fiber reinforced polymer (CFRP) strengthen the reinforced concrete silo as research object, considering the material nonlinearity of the reinforced concrete silo structure, use large finite element analysis software ANSYS to numerical simulate it,and get the stress, the displacement and the concrete crack distribution of the reinforced concrete silos reinforced with CFRP,and compared with the reinforced concrete silos which are not reinforced with CFRP.3.Study the influence of different CFRP reinforcement position, width, thickness and silo size on the effect of reinforcement.