Reliability Analysis And Design Of Circular Axial-Compressive Reinforced Concrete Columns Strengthened With CFRP Laminates

FRP (Fiber Reinforced Polymer) is a new composite material widely used in the concrete structure, which has the advantages of anti-corrosion and high strength. In China, we started to study and came to use the technique from later 1980s. In order to guide the design in the engineering, our country will issue the national technique code, i.e.'Technical Specification for Engineering Application with Fiber Reinforced Polymer', and the draft has been put out. In the draft, some terms may have problems, so this paper will check and amend it using a systematic and reasonable probability-based design philosophy.Firstly, evaluate the reliability level of the design method of FRP reinforced concrete columns in the'Technical Specification for Engineering Application with Fiber Reinforced Polymer'(Draft) with the JC and Monte Carlo method. The research results show that the effect of the load effect factor, concrete strength grade, FRP strength and FRP reinforcement ratio on reliability is great. The diameter of the column, steel strength and steel reinforcement ratio carry little weight. The variety of FRP strength and the uncertainty factor of calculation model are important factors on influencing the reliability.Secondly, evaluate the reliability level of the design method of FRP reinforced concrete columns in the ACI 440.2R-0X with the same method. The research results show that the same conclusion is got about the effect of the design variables and the load effect factor on reliability. It differs from the design method, the value of the design variables, the level of load, combination mode of load through comparing the two technique specifications, so it causes American's reliability slightly higher than China's.Finally, based on the reliability results, revise the capacity reduction factor of the design method of FRP reinforced concrete columns in the'Technical Specification for Engineering Application with Fiber Reinforced Polymer'(Draft), and put forward a suggestion value of 0.9. Introduce the performance design concept into the design of FRP reinforced concrete members, and put forward a new method for the design through making the reliability serving as a performance index.