Clay Ceramic Hollow Sphere - Cement Syntactic Foam Composite for Building Applications

The production of low-temperature clay lightweight aggregates is pursued eagerly as low energy and cost lightweight aggregate concrete (LAC) building blocks becomes more popular. Clay ceramic hollow spheres (CCHS) with waste glass (WG) additive was developed and studied as aggregate in cement composite. CCHS with diameter ranging in 6/8mm were produced by a sacrificial template technique with subsequent sintering under temperature of 900 °C and different WG content of 0, 5, 7 and 10 wt%. The effect of the sintering temperature and WG content on the physical properties and morphology of the CHS-cement composites were studied by means of optical microscopy and mechanical properties. Obtained composite materials were compared with commercially available lightweight fillers such as foamed glass granules and lightweight expanded clay aggregates (LECA). The results compressive strength of CCHS containing LAC is much higher from 4.8 to 7.1 MPa in comparison with the LECA-cement LAC - 3.5 MPa. Reduction of CCHS open porosity due to higher content of WG (10%) leads to lower absorption of cement paste, as result lower cement consumption, lower bulk density and compression strength. LAC with CCHS proved to be promising construction material due to low-temperature production process (i), widely available raw material (clay) and secondary material (glass cullet) use (ii), reduction of cement paste needed for material production (iii).