Research On Mechanical Behaviors Of Post-compressive Bi-prestressed Concrete Beam

Bi-prestressed concrete is also called tension and compression double-acting concrete, tension area of which could be made to bear pre-compressive stress and compression area could be made to bear initial tensile stress. Applying this system, the performances of concrete structure could be improved greatly. Both compressive stress in compression area and tensile stress in tension area could decrease in use stage. As a result, the section of concrete members could decrease while the span could increase.In this paper, the research contents comprise the following aspects: the experimental research on an anchorage equipment was made to test the effectiveness of anchorage system in post-compressive bi-prestressed concrete beam; construction technology and invert arch were studied based on the process of making concrete beams; from the aspects of deflection and beam section strain ,mechanical behaviors of two types of concrete beams were compared through static load tests; using finite element software ANSYS to simulate construction process and static load test and the calculation was compared with test results.It is shown that the anchorage system in concrete beam is effective and stress loss is calculated through anchorage test. Based on invert arch during construction process and static load test, it is shown that two types of concrete beam perform very well. Bi-prestressed concrete beam could meet the requirements of the application without increasing sectional height and shows its advantage compared with the prestressed one. The simulation of construction process and static load test with finite element software is feasible and the results can be the reference of design and construction.