Experimental Study On The Corrosion Resistance Of Basalt Fiber Reinforced Concrete In Chloride Environment

Basalt fiber reinforced concrete is widely used in all kinds of major projects.As a modification of ordinary concrete,it has good resistance to cracking and deformation.Basalt fiber concrete suffers erosion of various corrosive substances in practical engineering applications.The durability issue is particularly important.In this paper,on the basis of predecessors’ research results with 5.0%NaCl solution to simulate chlorine salt environment.This paper analyzes the effective porosity,mechanical properties,failure modes,crack evolution and chloride ion distribution of basalt fiber reinforced concrete and basalt fiber fly ash concrete in solution for 9 months.And the strength degradation model and chlorine ion diffusion model under chloride salt erosion were established.The analysis leads to the following conclusions:(1)In each stage of 9 months of soaking in the chloride solution and the normal water environment,the concrete blocks exhibited a good overall and slightly denuded.Compared with ordinary concrete,0.05%～0.10%basalt fiber concrete can effectively inhibit the generation and deterioration of surface cracks.With the continuous increase of fiber,the suppression effect begins to decline.Both basalt fiber and concrete fuse with each other.And it plays a role in strengthening and cracking concrete.(2)At the ninth month of erosion,the porosity of 0.10%fiber concrete was 9.70%lower than that of ordinary concrete.Fiber effectively inhibits the formation of concrete pores.Using the third month as a reference,the compressive strength breakage rates of ordinary concrete and 0.10%fiber reinforced concrete at the ninth month were 20.4%and 12.9%.Fiber effectively resists chloride attack and reduces strength loss.And 0.10%-0.20%of basalt fiber increase deform ability of concrete.The load displacement curve has obvious yield point and descending section.(3)When the fiber content is between 0%and 0.30%,0.1%fiber concrete has the lowest chloride ion content and the chloride ion permeability is the lowest.With the increase of erosion time,the chloride ion content in each test block gradually increased,and basically showed a linear change.0.10%fiber optimally slowed the linear upward trend;Compared with the same amount of fiber reinforced concrete,the corrosion resistance of basalt fiber and 10%fly ash incorporation into concrete is not significantly improved.(4)Based on the experimental data,this paper explores the damage-deterioration regularity of concrete in the environment of chloride salt erosion,and establishes a model of strength degradation under the influence of time and fiber content.Based on Fick’s second law,considering the influence of different factors,a chloride ion diffusion model of fiber concrete under chloride salt environment was proposed.This will provide a certain reference value for the prediction of the durability life of basalt fiber reinforced concrete structures exposed to chloride ions.