| The BFRP-concrete structures were experimentally studied and theoretically analyzed systematically. The main contents include two aspects: experimental study on the concrete beam with BFRP reinforcement; comparative study on the RC columns reinforced with BFRP cloth and CFRP cloth; experimental study on improving bearing capacity for the double arch bridge with BFRP cloth. Among which, the experimental study on reinforcing RC column and double arch bridge with BFRP cloth is first proposed at home and abroad.Twelve concrete simple-supported beams were made to conduct the tests of static load with different bars and reinforcement ratio of BFRP bar. In the tests, the loads were applied on three points until the beam was damaged. Twenty-one RC columns were made, including nine RC columns wrapped with BFRP, nine RC columns wrapped with CFRP, three RC columns without any reinforcement, to conduct the comparative study of axial compression. According to the mechanical properties of BFRP and the basic theory about the reinforced concrete flexural members, the finite element analysis is applied to the measurement of the anti-bending properties of the reinforced concrete simple-supported beam with BFRP. Based on the experimental and theoretical study, the static and dynamic properties of solid of the bridge pasted BFRP is researched, taking the dangerous and old arch bridge of Aohan as an example.This research can be divided into five parts:(1)The main physical and mechanical properties are obtained by the tensile test of eight BFRP bars. According to the defect of low tensile elastic modulus of BFRP bar, the study on the BFRP bar with high tensile elastic modulus is recommended.(2)According to the test results, it is recommended to produce the non-stripping BFRP bar and research the enhanced concrete beam with BFRP bar.(3)The result shows that the bearing capacity of the RC columns reinforced with the fibers increases obviously. The bearing capacity of the RC columns with CFRP is higher than that with BFRP, but the difference is not obvious. The displacement ductility factor increases, but its increase rate becomes slow with increasing layers of fiber cloth, so the most economical layer number is 3. Based on the confinement mechanism of FRP cloth and the calculation formula of the bearing capacity for common RC column, the formula of the bearing capacity for reinforced RC column with BFRP cloth is proposed. The result of calculation basically tallies with the number in experiment.(4)The overall trend of the load-deflection curve of concrete beam reinforced with BFRP is basically same as the simulation curve, but the deflections of the simulated values are generally larger than those of the measured values with the same load. The parameters input are specified value, indicating the value of the specification given are somewhat conservative. The values of N 2 N1of the reinforced concrete beam with BFRP are 1.17,1.16 and 1.12 respectively. According to the results, better non-peeling BFRP tendons, which have enough bonding strength with concrete, are suggested to be produced.(5)The test results indicate that the compressive stresses in the vault, the arch spring and other key sections can be effectively reduced by reinforcing the arch rib with BFRP cloth, and the flexural and torsional properties of the structure can be enhanced. The bridge has better whole working performance after being reinforced and it works in the flexible state. Bearing capacity increased to be 1.9 times of road-â…¡,having adequate safety margin.The results have great significance on the improvement of theoretical design of concrete structures, and provide the scientific basis for the application of BFRP in the field of concrete structures. At the same time, they can provide beneficial guidance for the engineering practice. |
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