The effect of waste marble and basalt aggregates on the fresh and hardened properties of high strength self-compacting concrete

With the increase in concrete production worldwide in recent years, our natural aggregate resources are rapidly depleting. Various waste aggregates are used as an alternative to natural aggregates to solve this problem. However, the demand for High Strength Self-Compacting Concrete (HSSCC) in the concrete industry is increasing. Using waste aggregates as coarse aggregate in HSSCCs may increase the sustainability of HSSCCs, while simultaneously reducing environmental waste problems and production costs. This study aims to produce the HSSCC series by using basalt and waste marble aggregates in certain volumetric ratios instead of limestone -based crushed stone used as coarse aggregate in concrete production. To achieve this aim, the effect of aggregate type was investigated on the physical, mechanical, and durability properties of the produced concrete series. In the production of HSSCC series, silica fume and cement were used in fixed proportions. Instead of limestone -based coarse aggregates, waste marble and basalt aggregates were used at 25, 50, 75, and 100 % ratios by volume. Thus, a series of eight different HSSCCs and a control HSSCC were created. Slump flow, T500 time, V -funnel, and L-box tests were applied to assess the flowability, filling, and passing ability of the produced HSSCC series. Cylindrical specimens of 100 x 200 mm and cubes of 150 x 150 x 150 mm were produced with the prepared mixture series. The produced specimens were subjected to standard curing for 28 and 180 days in lime -saturated water pools with a temperature of 20 +/- 2 celcius. After the curing period, ultrasonic pulse velocity, compressive strength, splitting-tensile strength, apparent porosity, sorptivity, rapid chloride permeability, electrical resistivity tests, and internal structure analyzes were applied to the specimens. According to the fresh concrete test results, no segregation was observed in all of the HSSCC series and it was observed that they were in compliance with the fresh state standards. When 180-day curing was applied to the HSSCC series, the compressive strength of the series in which 25 % waste marble aggregate was used increased by 9.1 % compared to the control series, while the compressive strength of the series in which 100 % basalt aggregate was used increased by 19.5 %. As a result, it has been observed that HSSCCs with high strength and durability properties can be produced by using basalt or waste marble aggregates at rates of 25 % to 100 % instead of crushed stone aggregates.