Experimental Study Of The Mechanical Properties Of Tailings Steel Fiber Reinforced Concrete

Tailings steel fiber reinforced concrete is a composite material which iron tailings sandare used instead of natural sand of fine aggregate, and steel fiber is added. The main study isthat how tailings replacement rates and steel fiber content impact the basic mechanicalproperties of the composites and the durability of tailings steel fiber reinforced concretecomposite material. In this paper, tailings steel fiber reinforced concrete composite materialsare studied by compression, flexural tensile, impermeability, corrosion, freeze-thawexperiments. Researches are mainly done as follows:（1）Preparation of steel fiber reinforced concrete tailings. Combined theoretical analysisand experimental researches, the key parameters like fine aggregate replacement rate and steelfiber content of iron tailings are studied. The influence of tailings concrete workability isdiscussed. The preferred range of tailings replacement rates and steel fiber content isdetermined.（2）Basic mechanical properties tests. Based on cube compressive tests and flexuraltoughness tests, compressive strength, flexural strength and toughness strength of tailings steelfiber reinforced concrete are researched. The tests shows: steel fiber is not obvious to improvecompressive strength of the tailings steel fiber reinforced concrete. With the increase of steelfiber content, the compressive strength of tailings steel fiber reinforced concrete first increasedand then decreased. When the steel fiber content is2%, the strength of the concrete begins toshows a downward trend. The obtained experimental data shows that: With the increase in thereplacement rate of tailings, tailings bending strength of steel fiber reinforced concrete firstincreased and then decreased. When tailings replacement rate is40%to60%, the flexuralstrength of tailings steel fiber reinforced concrete is larger and the bending toughness turnsbetter.（3）Durability tests. Based on impermeability, freezing and corrosion tests, the durabilityof tailings steel fiber reinforced concrete material can be studied. The impermeability oftailings steel fiber reinforced concrete is good; the mass loss rate and the dynamic elasticmodulus of freeze-thaw cycle decline less; the maximum reducing amplitude of concreteflexural strength is15.58%; the cube compressive strength is changed little after salt corrosion.It proves that tailings steel fiber reinforced concrete composite has good durability. （4）As applied research, bending performance study of part tailings steel fiber reinforcedconcrete beams stratified is carried out. Research shows that concrete bending strengthincreases with the increase of layer thickness of the tension zone of tailings steel fiber concrete.Under the condition of the same layered height and the same steel fiber content, the flexuralstrength of steel fiber reinforced concrete beams is the maximum when the tailingsreplacement rate of is40%. But part of the bending strength of tailings steel fiber reinforcedconcrete layered beam bending strength are less than steel fiber reinforced concrete beams.