Response to a real world need
All the time, concrete structures surround you. We feel convenience and safe in the structures. We are using concrete very well, and will keep riding on it and its improved form. Our research focuses on innovating our technology for concrete structures, materials and construction. Research articles published by the group can be found in Scopus database or Prof. Kim's CV
Rheology and construction performance
Slump and slump flow of concrete are requisitely measured. A rheological model, proposed in our group, converts the test results into the Bingham parameters such as yield stress and plastic viscosity. That would be the first step to start rheological evaluation on the construction performance of concrete.
Click the "Bingham parameters" button below the image
Advanced techniques have been developed to evaluate the rheological behavior of mortar. These new testing methods provide deeper insights into the rheological behavior of construction materials.
A new direction toward carbon utilization in construction industry
Aqueous CO2 curing technology does not need a huge chamber supplying gaseous CO2 for the early carbonation to enhance the performance of cement-based materials. CO2 is dissolved in an alkaline solution beforehand, and then blast-furnace slag mortar can be cured in the CO2 solvent. The resultant carbonation in early age improves the strength of the mortar samples together with a high CO2 uptake. In addition, the technology is easily augmented on the existing carbon capture process.
Han, S. H., Jun, Y., and Kim, J. H. (2022), The use of alkaline CO2 solvent for the CO2 curing of blast-furnace slag mortar, Constr. Build. Mater. 342: 127977, 2022, https://doi.org/10.1016/j.conbuildmat.2022.127977
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 JH, Lee JH, Kim YH, Equilibrium of capillary and pore water pressure in lightweight aggregates concrete, MECH ADV MATER STRUCT 2021, https://doi.org/10.1080/15376494.2021.1949510
Yoon JY, Kim JH, Mechanical properties of preplaced lightweight aggregates concrete, CONSTRUCT BUILD MATER 2019, https://doi.org/10.1016/j.conbuildmat.2019.05.010
Yoon JY, Lee JY, Kim JH, Use of raw-state bottom ash for aggregates in construction materials, J MATER CYCLES WASTE MANAGE 2019, https://doi.org/10.1007/s10163-019-00841-5