Development of lightweight aggregate geopolymer concrete with shale ceramsite

This paper developed a lightweight aggregate geopolymer concrete (LAGC) with shale ceramsite. 18 groups of LAGC specimens with 3 sand ratios (30%, 40% and 50%) and 6 aggregate contents (10%, 20%, 30%, 40%, 50% and 60%) were prepared. A series of static tests (dry density test and uniaxial compression test) and dynamic tests (ultrasonic pulse velocity test) were performed to achieve the dry density, compression strength and P-wave velocity. The effects of sand ratio and aggregate content on the dry density, compression strength and P-wave velocity were discussed. Two optimal mix proportions for the LAGC were proposed. The results show that the dry density and P-wave velocity increase as sand ratio increases. The compressive strength increases then decreases as sand ratio increases. In addition, the dry density and compressive strength decrease as aggregate content increases. The P-wave velocity increases as aggregate content increases. The LAGC with the sand ratio of 30% and aggregate contents of 30% reaches the dry density of 1378.0 kg/m3 and compressive strength of 18.5 MPa. The LAGC with the sand ratio of 30% and aggregate contents of 40% reaches the dry density of 1348.0 kg/m3 and compressive strength of 16.8 MPa. Both of the proportions satisfied the engineering requirements, which are recommended for the potential application in the construction.