Study On Mechanical Properities Of Reinforced Concrete Beams Under Simulatedacid Rain Environment

Deterioration of corroded concrete,corroded reinforcement bar,degradation of bond between the concrete and the reinforcement bar are the main causes of premature and serious deterioration of reinforcement concrete(RC)structures long before their designed service life.Durability of RC structures have become an important issue and attracted a lot of researchers worldwide.Mechanical properties of the corroded RC materials and the bond behavior between the corroded RC are studied in this paper which based on the systematic investigation of the literatures and funded by a National Science Funded project.The main contents are as follows:Firstly,to investigate the compressive performance of concrete in different strain rate corroded by simulated acid rain,including 120 cube specimens,4 series of accelerated corrosion tests was executed on concrete C30.The physical and mechanical properties(including surface,mass,compressive,failure mode et al)of concrete in the different corrosion degree are researched.Secondly,considering bond property between reinforcement bar and concrete,and analyzing the material constitutive relationship of reinforced concrete structures,a Finite Element model was established.The influences of steel bar,concrete and bond property are studied on the mechanical property of RC member.Firstly,the bearing capacity of a reinforced concrete beam is analyzed by finite element analysis,and the validity of the model is verified;Secondly,under the action of concentrated load,the finite element analysis of reinforced concrete beams under single factor and multiple factors is carried out,and the changes of mechanical properties such as mid span deflection,bearing capacity,reinforcement stress distribution and relative slippage are discussed;Lastly,the finite element analysis of the corroded reinforced concrete beam under multiple factors is carried out under the action of moving load,and the variation rule of its mid span deflection and speed is studied.It is concluded that the bond deterioration between corroded concrete and steel bar must be considered in Finite Element analysis of the corroded CR component(structure).