Experimental Study On Friction Loss And Anchor Prestressed Detection System Of Prestressed Concrete Bridge

Build the model of entity prefabricated beam by the large-scale finite element software Midas/Civil,calculation of the prestressed bundle theory elongation and the value of the prestress loss of each node,export the distribution map of the effective prestress of each steel bundle.In the construction site do the friction test,the the steel bundle theory elongation is used to verify the actual elongation during the experimental process.according to the experimental results,actual coefficient u,k,real time monitoring of the prestress loss of the prestressed steel after the experiment finished,research the relationship between friction loss and total loss.One prestress testing system been development,it is proved that the test result is reliable by the field standard test,the detection system is applied in practical engineering,according to the actual situation,puts forward three criteria for evaluating the quality of prestressed construction,in view of the problem of poor quality of prestressed construction,the corresponding measures are put forward,comparative and analysis two detection results that belong to before and after take measures.Study found: It had little difference between the theoretical and actual measurement elongation of steel bundle;The friction coefficient u,k,compared with the standard value has a larger deviation;Friction loss accounted for a large proportion of total loss;The detection value of the single cable effective prestress is in complete agreement with the corresponding pressure ring;late detection results were significantly better than the early detection results,Research results show that:(1)The experimental data obtained by this friction test have high precision,the coefficient obtained from this experiment can accurately estimate the friction loss on the spot,related results have great significance to improve the quality of the construction and maintenance of the project at later stage;(2)The friction coefficient has a certain discrete type,and the proportion of total loss is large,It is better to do the friction test on site for complex or important or large quantities of projects,to ensure the structure has sufficient pre stress;(3)The problems in the prestressed construction had been solved by the improved measures,the construction quality of prestressed can be improved by using the prestress testing system and three evaluation standards,the prestress testing method been development is reliability,and the operation is simple,convenient and low cost,it has a very good social promotion value.