The Quasi-static Load Experimental Research Of Prestressed Concrete Beam Under Simulated Acid Rain Environment

Prestressed concrete structures are widely used in various fields such as civil engineering,construction,water conservancy and transportation engineering with their superior performance.However,the existing prestressed concrete structures have been corroded by corrosive media for a long time,resulting in the reduction of concrete strength,steel corrosion,stress relaxation and other sites,which directly affect the seismic resistance of concrete structures,thus making many prestressed concrete structures far below the design life.Destruction occurred in advance.At present,most scholars at home and abroad are exploring the performance degradation law of prestressed concrete structures by energizing accelerated corrosion.This is quite different from the actual environment,and the shape and nature of the steel bars and prestressed tendons in the energized environment.The difference under the conditions is large.Therefore,in this paper,the prestressed concrete beam is subjected to full immersion corrosion with a long period of 11 months by artificially simulating the acid rain environment,and then the corrosion time,tensile control stress,concrete strength and chloride ion concentration are studied by low-cycle reciprocating loading test.The influence of parameters on its seismic performance and the deterioration of seismic performance.The main contents are as follows:(1)Experimental design four groups to contracted and 9 pre-stressed concrete beams producted by salt-mixing method.At the same time,In the simulated acid rain environment,the whole immersion method was used for the corrosion of the period(2500 h,5000 h,7500 h),and the phenomena and reaction rate during the corrosion process were recorded and observed.(2)Under the low-cycle reciprocating load,study the failure process and the final failure mode of the test beam,and analyze the bearing capacity degradation,and compare the four parameters to influence the corrosion.(3)Collating test data,drawing skeleton curve and hysteretic curve and analyzing stiffness degradation and energy dissipation capacity of the test beams.The seismic performance of the corroded prestressed concrete beams is compared under different gradients and different parameters.