Publicacións

@article{nduka_assessment_2023,

title = {Assessment of Water Transport and Chemical Attack of Meta-Illite Calcined Clay Blended Cement in High-Performance Concrete},

author = {David O. Nduka and Babatunde J. Olawuyi and Blas Cantero-Chaparro and Belén González-Fonteboa},

url = {https://www.mdpi.com/1996-1944/16/22/7149},

doi = {10.3390/ma16227149},

issn = {1996-1944},

year  = {2023},

date = {2023-01-01},

urldate = {2026-08-13},

journal = {Materials},

volume = {16},

number = {22},

pages = {7149},

publisher = {Multidisciplinary Digital Publishing Institute},

abstract = {Rapid urbanisation causes a rise in the need for infrastructure, which in turn fuels the creation of additional concrete and further increases cement supplies. Activation of illite-based clay mineral and usage in concrete production is one of the sustainable ways to address the cement industry anthropogenic issues. This study evaluates the durability properties of water transport (water absorption, and capillary water absorption), and resistance to aggressive environments (5% solutions of hydrochloric acid, HCl; sodium sulphate, Na2SO4; and calcium chloride, CaCl2) of meta-illite calcined clay (MCC)-based high-performance concrete (HPC). For this purpose, concrete was produced with 5, 10, 15, 20, 25 and 30% MCC content in partial substitution of CEM II. Results from the water absorption tests indicate an average percentage value of 3.57%, 3.35% and 2.52% for all the observed mixes at 28, 56 and 90 days, respectively, with MCCC-10 HPC having an average best value of 2.23% across the curing ages. On all observed days, the 5 to 15% cement replacements had very close average water sorptivity value of 0.125 ± 0.001 mm/min0.5 with the control mix (0.113 ± 0.011 mm/min0.5). The aggressive environments exposure findings of the hardened MCC-based HPC specimens of 10 to 20% recorded an approximately 15% compressive strength loss in HCl, Na2SO4 and CaCl2 solutions over the 90 days of curing. In all, the HPC mixes of 5 to 15% MCC content obtained an average durability performance factor of 89%. As a result, these findings imply that MCC can replace cement in up to 15% of HPC production.},

keywords = {durability properties, high-performance concrete, meta-illite calcined clay, superabsorbent polymers},

pubstate = {published},

tppubtype = {article}

}

@article{nduka_assessment_2022,

title = {Assessment of the Durability Dynamics of High-Performance Concrete Blended with a Fibrous Rice Husk Ash},

author = {David O. Nduka and Babatunde J. Olawuyi and Olabosipo I. Fagbenle and Belén González-Fonteboa},

url = {https://www.mdpi.com/2073-4352/12/1/75},

doi = {10.3390/cryst12010075},

issn = {2073-4352},

year  = {2022},

date = {2022-01-01},

urldate = {2026-08-10},

journal = {Crystals},

volume = {12},

number = {1},

pages = {75},

publisher = {Multidisciplinary Digital Publishing Institute},

abstract = {The present study examines the durability properties of Class 1 (50–75 MPa) high-performance concrete (HPC) blended with rice husk ash (RHA) as a partial replacement of CEM II B-L, 42.5 N. Six HPC mixes were prepared with RHA and used as 5%, 10%, 15%, 20%, 25%, and 30% of CEM II alone and properties are compared with control mix having only CEM II. The binders (CEM II and RHA) were investigated for particle size distribution (PSD), specific surface area (SSA), oxide compositions, mineralogical phases, morphology, and functional groups using advanced techniques of laser PSD, Brunauer–Emmett–Teller (BET), X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared/attenuated total reflection (FTIR/ATR), respectively, to understand their import on HPC. Durability properties, including water absorption, sorptivity, and chemical attack of the HPC samples, were investigated to realise the effect of RHA on the HPC matrix. The findings revealed that the durability properties of RHA-based HPCs exhibited an acceptable range of values consistent with relevant standards. The findings established that self-produced RHA would be beneficial as a cement replacement in HPC. As the RHA is a cost-effective agro-waste, a scalable product of RHA would be a resource for sustainable technology.},

keywords = {durability properties, high-performance concrete, Rice husk ash, superabsorbent polymers, Sustainability},

pubstate = {published},

tppubtype = {article}

}