Study On Durability Of Polymer Steel Fiber Reinforced Concrete For Steel Bridge Deck Pavement

With the rapid development of steel box girder bridge technology and its wide application,bridge deck pavement disease has become one of the recognized technical problems in the world.At present,the main paving material of the bridge type is mainly asphalt,but the asphalt paving material still has great problems in durability and stability.In this paper,based on the recent researches on the mechanical properties of Steel Fiber Reinforced Polymer Concrete(SFRPC)and its engineering application in steel bridge deck pavement,theoretical analysis,experimental research and numerical values are combined.The simulation method is studied from the aspects of SFRPC’s micro and physical properties,environmental durability,weariness durability and so on:The first point,Numerical analysis of polymer steel fiber reinforced concrete based on durability.By comparing the presence or absence of steel fiber,the stress intensity factor value of the crack tip,the stress concentration extreme value and the displacement extreme value change indicate the resistance of the steel fiber.Cracking benefit;The study found that the incorporation of steel fiber in the encircled integral model reduced the maximum displacement of the crack by 26.01%,the maximum stress by 60.42%,and the crack tip stress intensity factor by 49.34%.Second point,For the study of environmental durability,the maintenance methods and special environmental factors were added to simulate different environmental scenarios in the actual project: high and low temperature circulation,high and low temperature water bath and sulfate erosion.The results show that the temperature of SFRPC decreases gradually from-15°C to 60°C under different temperature gradients,ranging from 21.66 MPa to 17.65 MPa,which is compared with ordinary concrete at 30°C and 60°C.It is known that the strength of SFRPC is 2.13 times and 2.85 times of that of ordinary concrete respectively;when the temperature of SFRPC is from low temperature-15°C to high temperature 6°C under different temperature water bath,the strength gradually decreases,ranging from 20.36 MPa to 15.68 MPa.In the anhydrous high-temperature cycle environment,the flexural strength of SFRPC was reduced to 11.69% and the lowest 6.01% under water bath conditions.SFRPC found in the antisulfate attack test: under the same conditions,the corrosion resistance of SFRPC was 81.31%.The ordinary concrete has a corrosion resistance of 69.33%.Third point,The bearing fatigue fatigue test of SFRPC material is carried out.The fatigue equation of SFRPC is obtained by Weibull two-parameter and three-parameter distribution function: Weibull two-parameter P-S-N fatigue life equation: S-lgN: S=A-0.10005 lgN,lgS-lgN: lgS=lga-0.06974lgN;Weibull three-parameter P-S-N fatigue life equation: S-lgN: S=A-0.10063 lgN,lgS-lgN: lgS=lga-0.07012 lgN.According to the variation of the fatigue stress-strain curve of the specimen under the fatigue test,the internal strain of the specimen is gradually superimposed with the load cycle,the fatigue strain becomes larger and larger until the damage,and the maximum strain value before the failure is between 1300με~1500με.The residual fatigue strain value is between 500με~1200με;according to the variation law of the elastic modulus of the test piece with the increase of the number of cycles: as the number of cycles increases,the elastic modulus of the material gradually decreases until the test piece is destroyed,and the elasticity is broken.The modulus average is 58.56% of the initial modulus,and the internal damage evolution equation of the SFRPC specimen was obtained.