Life Cycle Assessment Of RC Beams Based On The FRP Strengthened Design Standards Of China, The US And Japan

ABSTRACT:Life cycle assessment (LCA), as an objective evaluation instrument of environmental impact of the construction, starts to be used.With the speeding up of urbanization in our country, the appearance and functions of large number of reinforced concrete structures have not been able to meet the existing requirements. According to relevant statistics, it is shown that currently more than30%of the total building structure appears the signs of failure and has entered into a functional degradation period. Base on the LCA, evaluating the environmental impact of the structures after strengthing can promote the environmental friendliness of strengthened structures. In the meantime, due to the study is insufficient currently, therefore, it has important academic value in this field.Fiber reinforced polymers(FRP) have been used extensively in the retrofitting and strengthening of concrete structures,due to its characteristics of ultrahigh strength, high elastic modulus,high temperature and corrosion resistance. The FRP retrofitting technology,which has been adopted by the developed countries represented by the United States and Japan,is continuing to mature,while it started late in China.With the decrease of the FRP production cost,the application of FRP will continue to increase. Therefore,it is necessary to compare the FRP strengthened standards of China, the US and Japan detailed to improve China’s standard and evaluate the effect of FRP to the environmental impact of concrete structures.The main contents of this paper is shown as follow:(1) Based on the eco-indicator method, a life cycle assessment of FRP reinforced concrete beam was proposed. This will lay the foundation of comprehensive environmental impact quantitative evaluation of strengthening reinforced concrete beams based on the standards of China, the United States and Japan.(2) The three standards were compared in the following several aspects:a. fiber; b. ancillary adhesives; c. FRP performance. Then, some suggestions were given to improve the material performance requirements in China’s standard.(3) Based on the environmental impact assessment of a simply reinforced concrete beam flexural strengthened with FRP under the standards of China and the United States, the standard design methodology differences in the carrying capacity of FRP flexural strengthening were presented, and some proposed changes were given. (4) Based on the renvironmental impact assessment of a simply reinforced concrete beam shear strengthened with FRP under the standards of China, the United States and Japan, the standard design methodology differences in the carrying capacity of FRP shear strengthening were presented, and some proposed changes were given.