SOME MECHANICAL PROPERTIES OF WASTE MARBLE AGGREGATE CONCRETE REINFORCED WITH LOCAL STEEL PINS AS STEEL FIBERS

The research aims to use waste materials in concrete to decrease cost of concrete since that waste materials in Iraq is highly available. Waste marble is very good example to use it in concrete as coarse aggregate and excellent material to produce very good quality concrete. This research study the using of waste marble as coarse aggregate and using steel pins as a low cost local steel fibers as percentages of total volume in concrete and study the effect on mechanical properties of concrete. Using marble aggregates in concrete increase the compressive, tensile and flexural strength of concrete comparing with ordinary aggregate concrete. Ordinary reference mix concrete with 1:1.1:2.2 gives about 50.89 MPa, while using marble aggregate with same mix proportions gives 57.07 MPa, thus, that gives low cost for production of concrete because 60%to 70% of the volume of concrete is aggregates . The effect of steel pins as it used in marble aggregate concrete is also very good , using 0 %, 0.1% ,0.2% , 0.3%, to 1% of steel pins in mixes. The compressive increase by adding steel pins from 57 to 72.14 MPa. Flexural strength had very significant increment when adding fibers and it rise from 3.9 to 8.6 MPa.