Experimental Study On Splitting Tensile And Flexural Tensile Properties Of Aligned Steel Fiber Reinforced Cement Mortar

Aligned steel fiber reinforced cement mortar refers to the new building material where steel fibers are directional alignment in the matrix according to the direction of the tensile stress.Its mechanical properties are significantly higher than that of ordinary steel fiber reinforced cement mortar,especially when it comes to the tension and flexural tensile.In the field of engineering application,quantities of important structural components bear the tension and flexural tensile force.So the researches on the mechanical properties and flexural toughness of the aligned steel fiber reinforced cement mortar are significant to its application in engineering.In view of this,the splitting tensile strength,flexural strength and flexural toughness of aligned steel fiber reinforced cement mortar are studied in this paper,using the test methods of The Steel Fiber Reinforced Concrete JG/T 472-2015 and ASTM C1609.The splitting tensile strength and flexural tensile strength of aligned steel fiber reinforced cement mortar are studied.The results show that the splitting tensile strength and flexural tensile strength of aligned steel fiber reinforced cement mortar are apparently higher than that of ordinary steel fiber reinforced cement mortar.Along with the increase of the orientation degree of steel fibers,the volume content and the matrix strength,the splitting tensile strength and flexural tensile strength are increased.For the steel fiber reinforced cement mortar with different steel fiber shapes,the hooked steel fiber cement mortar shows the largest splitting tensile strength and flexural tensile strength,and the circular straight shape is at the second place while the wave shape shows the smallest strength,when the water cement ratio of matrix and fiber content of steel fiber cement mortar are the same.The test results of the flexural toughness of aligned steel fiber reinforced cement mortar and ordinary steel fiber reinforced cement mortar are studied.Results show that compared with ordinary steel fiber reinforce cement mortar,the flexural toughness of aligned steel fiber reinforced cement mortar is higher,and its load deflection curve is more plentiful where appears two peak values.The flexural toughness is also related to the volume fraction,fiber type and the matrix strength.With the increase of matrix strength and volume fraction of fiber,the flexural toughness increases.The hooked steel fiber has the most significant effect on the toughness of cement mortar and the circular straight shape is at the second place while the wave shape shows the smallest effect.On basis of the research of fiber’s drawing property,the splitting tensile strength calculation model of the aligned steel fiber reinforced cement mortar and the random-oriented steel fiber reinforced cement mortar is established.The splitting tensile test values are in accordance with the calculated values.According to the model,the splitting tensile strength of steel fiber reinforced cement matrix composites is gradually increased with the increase of fiber bond strength and fiber length.