Sustainability and lightweight aggregates

Our interests in the lightweight aggregates originate from the recycling of industrial by-products. Artificial (coarse) lightweight aggregates is produced by sintering coal-combustion ash and dredged soil, and we also use bottom-ash lightweight sand as it is. Consuming the ashes for producing concrete contributes to the sustainability of construction industry. However, their porous properties make it hard to have a stable concrete mixture. An equilibrium on the capillary pressure and pore suction of surround pastes accounts for the water absoprtion of the porous lightweight aggregates in the fresh-state mix. A physical model is proposed to consistently evaluate that of bottom-ash lightweight sand or coarse lightweight aggregate.

Kim, J.H., Lee, J.H., Kim, Y.-H., Equilibrium of capillary and pore water pressure in lightweight aggregates concrete, Mech. Adv. Mater. Struct., 2021, https://doi.org/10.1080/15376494.2021.1949510

Kim, Y.-H., Park, C.B., Choi, B. I., Shin, T.Y., Jun, Y., Kim, J. H., Quantitative Measurement of Water Absorption of Coarse Lightweight Aggregates in Freshly-Mixed Concrete, Int. J. Concr. Struct. Mater. 14: 34, 2020, https://doi.org/10.1186/s40069-020-00408-x

Preplaced lightweight aggregates concrete

The special construction technique is also proposed to get rid of the instability and poor workability of the materials. Fill a form with dry lightweight aggregates, and then inject grout in the empty space among aggregate particles. This two-stage casting process solve the tedious problems when we apply the lightweight aggregate concrete.

Yoon, J.Y., Lee, J.H., Kim, J.H., Use of raw-state bottom ash for aggregates in construction materials, J. Mater. Cycles Waste Manag. 21: 838–849, 2019, https://doi.org/10.1007/s10163-019-00841-5

Yoon, J.Y., Kim, J.H., Mechanical properties of preplaced lightweight aggregates concrete, Constr. Build. Mater. 216: 440–449, 2019, https://doi.org/10.1016/j.conbuildmat.2019.05.010

21MAMS lighweight aggregates in equilibriam.pdf
20IJCSM lightweight aggregates in air.pdf