Experimental Study On Strengthened Damaged Prestressed Concrete Hollow Slab Beam With Prestressed CFRP

Prestressed technology is the most revolutionary structural conception in the field of concrete structure engineering in twentieth Century.It has been widely used in civil engineering and building engineering.The bridge loading reinforcement after reinforcing material strain(stress)behind this shortcoming of prestressed CFRP plate and bridge reinforcement,can effectively improve the utilization value of materials,technology is expected to fundamentally solve the reinforcing material strain strengthened with prestressed CFRP plates(stress)lag the problem.In order to develop a reliable and permanent anchorage system and a simple and effective tensioning system,it has been successfully applied to the actual bridge reinforcement project.The main research contents and achievements are as follows: the research and development of prestressed CFRP plate strengthening and reinforcing effect test are carried out:(1)The deficiency of the universal testing machine measuring carbon fiber plate anchorage anchorage performance test for traditional,based on the laboratory 10 m long steel box girder as stretching bed,developed a full-scale tensioned and anchored prestressed CFRP plate anchorage performance test device;and the prestress loss and anchorage performance of carbon fiber plate round tooth plate anchor;(2)In order to solve the problem of the poor anchorage performance of the traditional prestressed CFRP plate anchor,a new type of flat anchor with a rough surface of circular teeth is developed,which has the advantages of good mechanical performance and high anchoring performance;(3)Carbon fiber plate anchorage on the traditional tensioning method was improved,a drawing rod abandoned anchor tension anchor,establish a prestressed carbon fiber plate with high efficiency and convenient self anchoring method;(4)Static damage test and evaluation of the damaged prestressed concrete hollow slab beam are carried out,and the self designed circular toothed anchor and tension self anchored device are used to evaluate the reinforcement.The test results showed that the circular tooth anchorage tension of self anchored system can be reliably used in practical engineering;analysis before and after the reinforcement of hollow slab beam static load test results,further confirms the reinforcement technology of prestressed CFRP plate can inhibit hollow beam deflection strain growth.