Test Study On Mechanical Properties Of Corrosion Of Prestressed Concrete Structure

A study of prestressed concrete beam under corrosion fatigue conditions is an important aspect of engineering durability problems. The structure or components withstand the repeated loading , although the stress is less than the material yield limit, but it usually occurs fatigue damage in the repeated loading. Practical engineering structures are used in certain environmental conditions in service, the external environment will cause varying degrees of corrosion of the structure. The structure accompanied by fatigue failure of the corrosion, corrosion accelerated fatigue failure. So the structure usually occurs corrosion fatigue damage in the joint action of cyclic stress and corrosion media. The thesis is an important part of the project of National High Technology Research and Development Program(863 Program)—"Based on fatigue life of concrete bridge structure and design method" , studys the mechanical properties of prestressed concrete structures affected by corrosion, the contents of which include six chapters as follows.In the first chapter, the significance of this study and the relevant literatures are expounded. Meanwhile, the historial and present background of the research on corrosion fatigue of prestressed concrete is introduced systematically. Based on the existing problems, the objectives of this paper are put forward.In the second chapter, the experimental programs including the mechanics properties of material, details of beam specimens, apparatus of static and fatigue test are introduced.In the third chapter, experimental research is carried out on different corrosion rate beam subjected to static loading, explores the damaged features of the beam specimens under static load patterns, comparative analysis the test results of different corrosion rate beams , including deflection, concrete strain cross-section, reinforced stress .In the fourth chapter, experimental research is carried out on different corrosion rate beam subjected to static loading, explores the damaged features of the beam specimens under fatigue load patterns, comparative analysis the test results of different corrosion rate beams , including fatigue life, concrete strain cross-section, reinforced stress . According to the results under the fatigue loading, explores the damaged features of the beams specimens , tests and verifies the theory of the horizontal section assumption. In the fifth chapter, the deformation rule of beams strengthened under fatigue loads is analyzed according to experimental results. Then, residual deflection and loading deflection are taken into consideration discussed, the calculation formula of the total deflection is obtained.