Mechanical Properties Of Freeze-thaw Damage Of Cement-based Materials Based On Synergistic Effect Of Slag Powder And Graphene Oxide

Graphene oxide can improve the structure of cement matrix,thereby greatly improving the macroscopic properties such as strength,toughness and durability of cement-based materials,and has broad application prospects in the field of composite materials.Studies have shown that the use of graphene oxide alone reduces the workability of cement-based materials,while mineral admixtures such as slag powder can significantly improve the performance of cement-based materials.Therefore,this paper studies the performance of cement-based materials based on the synergistic effect of slag powder and graphene oxide under freeze-thaw damage conditions.The main research contents include:1)Considering the three influencing factors of slag powder content,graphene oxide content and water-to-binder ratio,the orthogonal test scheme is designed.The fluidity of cement mortar is obtained through test and test,and the variation of fluidity with various factors is further analyzed.Using the range analysis method of orthogonal test,the sensitivity of fluidity to various influencing factors was studied,and the corresponding optimal ratio was obtained.2)Using the rapid freezing method of the laboratory to study the frost resistance of cement-based materials under the synergistic effect of slag powder and graphene oxide,and analyze the anti-freeze performance indexes of cement-based materials such as appearance,mass loss rate and relative dynamic elastic modulus.A trend that varies with each influencing factor.The orthogonal test method was used to study the sensitivity of antifreeze performance to various influencing factors,and the corresponding optimalratio was obtained.3)Study the mechanical properties of cement-based materials after freeze-thaw damage,and test the compressive and flexural strength of cement-based materials by uniaxial compression test and three-point bending test.The variation of mechanical properties with the three influencing factors of graphene oxide and slag powder content and water-to-binder ratio was analyzed.The range analysis method of orthogonal test was used to study the mechanical properties of freeze-thaw damage sensitive to various influencing factors.Sex,and get the corresponding best mix ratio.Scanning electron microscopy was used to observe and analyze the microstructure and microscopic changes of cement-based materials,and to analyze the antifreeze performance and mechanical properties after freeze-thaw damage from a microscopic point of view.