Study On The Fatigue Properties Of Polypropylene Fiber Reinforced Self-compacting Concrete Beam

In this dissertation the Experiments were designed to found the proportions of polypropylene fiber reinforced self-compacting concrete which can meet the standards of its working performance and mechanical property.Then the test of mechanical performance of polypropylene fiber reinforced self-compacting concrete was initialized.According to the relevant test specification for concrete structures,experiments of three sets of polypropylene fibers-Experimental Study of Reinforced self-compacting concrete beams were carried out: the first two group of experiments are about the three-point bending static loading test and Fatigue loading test indifferent proportion of polypropylene fiber;the third group test load for different levels of stress test beam three-point bending fatigue.Changes in fatigue test and load in the first through the first set of test beam static experiments of different mixing amount of polypropylene fiber reinforced concrete beam deflection and stiffness of reinforced concrete stress strain and crack,and thus as a basic reference in the second group,the third group of the present invention fatigue loading results;secondly,according to the second group and the third group of test beam load test and analysis of different polypropylene fiber content and different stress level test beam deflection,stiffness,beam fracture height and fracture density,length and the maximum width,coagulation soil and tensile strain of the steel with fatigue load cycles.In this paper,the main research contents are as follows:1 After consulting and analyzing the related polypropylene fiber self-compacting concrete with than the design specifications and documents,to meet the requirements of the working performance and mechanical properties with ratio design,and corresponding test cube compressive strength,axial compressive strength,elastic modulus,splitting tensile strength,flexural strength of mechanical properties test.2 Through the reinforced self-compacting concrete beams,12mm0.10% and 12mm0.15% volume content of polypropylene fiber reinforced self-compacting concrete beams flexural performance test research,analyzes the different volume content of polypropylene fiber concrete beams on the cracking load,yield load,limit load and fracture morphology of impact,mid span deflection of beams,reinforced and concrete strain and load size or number of times of fatigue loading curve.3 Based on the theory of fatigue analysis of the polypropylene fiber reinforced self compacting concrete beams in different should stress level under repeated loading of S-N curve.Through fatigue test of test beam deflections and crack development situation,combined with the stiffness degradation of the different stress level fatigue loading on the fatigue damage accumulation effect.4 By using ANSYS software,the contact of the ordinary reinforced self-compacting concrete beams and the 12mm0.15% volume content of polypropylene fiber reinforced self-compacting concrete beams,flexural performance analysis of material nonlinearity,and the numerical analysis results and the test results were compared,given the cracks in the test beams under static loading and distribution of concrete the first principal stress and axial stress of reinforced polypropylene fiber for 12mm0.15%.The volume content of reinforced self-compacting concrete beams subjected to different numerical simulation of fatigue loading stress level,comparison of testing results,analyzed by ANSYS software of polypropylene fiber reinforced self-compacting concrete beam fatigue life prediction feasibility of the earth.