Study On Durability Of C60 Prestressed Concrete Sleeper And Engineering Application

As an important part of the railway track system,sleepers play an important role in positioning the rails and transmitting the vertical and horizontal loads.After hundreds of years of development,the original wooden sleepers with poor corrosion resistance are gradually replaced by concrete sleepers,but the durability of the concrete sleepers has not been improved correspondingly.The service life of the concrete sleepers is not so long.Ideally,a large number of sleepers need to be repaired and replaced before the design life.Therefore,it is of great practical significance to strengthen the research on the durability of concrete sleepers and analyze the influencing factors of the durability of concrete sleepers.In this paper,the durability of type ? C60 concrete sleeper is studied.The influence factors of the durability of concrete sleepers are analyzed from the aspects of materials,structural forms and application environmental conditions through data research;the chloride ion resistance of C60 concrete sleepers under different maintenance conditions is studied through test comparison in accordance with the test method standard of GB/T50082-2009<standard for long term performance and durability test methods of ordinary concrete>.The experimental results show that the conditions of steam curing are more conducive to the growth of durability of concrete sleepers than that of ordinary curing.By adding different kinds and amounts of mineral admixtures,the influence of common mineral admixtures on the durability of concrete sleepers is studied,and the degree of the influence is compared(1)The increase of fly ash content is beneficial to the increase of chloride penetration resistance in the later stage of the test piece,while the addition of ground slag powder has little contribution to the chloride penetration resistance of the test piece.(2)Adding mineral admixtures can improve the frost resistance of the test piece,and when the content is about 30%,the frost resistance of the test piece is the best;Single or complex mineral admixtures have little effect on the frost resistance of the test piece.(3)In the time stage of the test,the test piece with mineral admixture shows stronger anti carbonization performance.When the fly ash and slag powder are mixed in proportion,the anti carbonization performance of the test piece is stronger than that of the single mineral admixture.Finally,according to the example of Laiyang sleeper yard,the influence of the concrete sleeper pouring,the natural environment,the materials,the mix proportion and the maintenance mode on the durability of type ? a C60 concrete sleeper is analyzed.