Development of Ultralightweight Cement Composites with Low Density and High-Specific Strength Using Hollow Glass Microspheres

AbstractThis paper investigated hollow glass microspheres (HGMs) on the density, mechanical properties, and durability of ultralightweight cement composites (ULCCs). The influences of HGMs on the microstructure developments of ULCCs were also studied. The results indicated that the ULCCs had a 1-day density ranging from 778 to 948 kg/m3 and 28 days compressive strength ranging from 22.9 to 33.1 MPa. The density of ULCCs was decreased with the increasing amount of HGMs, while the mechanical properties were reduced accordingly. The newly developed ULCCs with an HGM-to-binder volume ratio of 5∶1 and water-to-binder of 0.58 has a 1-day density of 778 kg/m3 and 28 days compressive strength of 22.9 MPa, whose specific strength was 0.029 MPa/Kg/m3. Furthermore, the obtained ULCCs showed a good resistance to chloride ion penetration. The microstructure demonstrated that the pozzolanic reaction of HGMs resulted in denser hydration products, which exhibited beneficial impacts on the durability of ULCCs.