REPLACEMENT OF NATURAL AGGREGATES WITH STEEL SLAG AND RECYCLED AGGREGATES IN PAVING BLOCKS

Abstract

Natural resources for the purpose of construction have become so scarce that researchers have been discovering alternatives to substitute the natural aggregates. In this report, properties of the recycled aggregates (both concrete and masonry) and steel slag were studied along with natural aggregates to replace natural aggregates when constructing paving blocks. Various mix proportions were worked out by varying the combination of materials. The mix proportion suitable for making M40 grade paver blocks was identified. In the various combinations steel slag was substituted for coarse aggregate materials in different percentages such as 25, 50, 75, 100% and recycled aggregates were substituted for fine aggregates as 20, 40, 60, and 80,100%. The combination C50F20 seems to be the best combination among all other combinations. Comparison of laboratory made paver blocks and factory made paver blocks were done using the optimum percentage combination and the difference was less than 1% for compressive strength and water absorption. This combination was chosen for conducting plate load tests to study the deflection behaviour of pavement sections. FEA based ANSYS software was used to validate the plate load test. Maximum deflection was observed when the test was done experimentally. It was observed that even-though steel slag and recycled aggregates does not have same values for properties of aggregates, they can meet the required values of the same and can be used in the construction of paving blocks at suitable replacement ratio. From the present study, the combination worked out to be suitable for upto medium traffic conditions.