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Eyo Umo Eyo

Bio: Eyo Umo Eyo is an academic researcher from Coventry University. The author has contributed to research in topics: Cementitious & Cement. The author has an hindex of 8, co-authored 19 publications receiving 148 citations. Previous affiliations of Eyo Umo Eyo include Fugro & University of the West of England.

Papers
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Journal ArticleDOI
TL;DR: RoadCem (RC) is an additive produced based on nanotechnology and comprises of synthetic zeolites and alkali earth metals as some of its components as discussed by the authors, and the geotechnical properties of a soil stabilized by adding RC to partly replaced cementitious materials are studied.
Abstract: RoadCem (RC) is an additive produced based on nanotechnology and comprises of synthetic zeolites and alkali earth metals as some of its components. The geotechnical properties of a soil stabilized by adding RC to partly replaced cementitious materials are studied. Various combinations of the additives were investigated with the objective of reducing the amount of OPC by 50% by an inclusion of RC and ground granulated blast furnace slag (GGBS) in the stabilized soil. Laboratory studies involving index property testing, oedometer swell-deformation, unconfined compression tests and microstructural examinations were carried out on both the natural and 7-& 28- day cured samples of the stabilized soil. The influence of RC on the mechanical properties of the stabilized soil was examined by comparing the performance of the stabilized soil mixtures that contain the RC and the mixtures without the RC added. Results indicated the positive effect of RC as noticed by the tremendous strength gain in 7 days with the OPC reduced by 50% in the stabilized soil. Swelling decreased significantly to 0% after 28 days curing with the settlement also reasonably reduced for nearly all the percentages of the OPC substituted. The stabilized soil’s microstructure revealed the mechanism of cementation observed as an encapsulation or “wrapping effect” as a result of the presence of RC. A comparison of the RC-modified soil containing the by-products GGBS and PFA indicated that GGBS was more effective in the enhancement of engineering properties than PFA. Overall, as well as meeting some of the standards set for road pavement applications, the results obtained from this research are very promising for the ongoing discussions on reducing carbon foot-printing by OPC replacement.

42 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of high plasticity on swell potential, swelling pressure and micro-structural characteristics of kaolinite-bentonite mixed clays was presented, and the results showed that reduction in plasticity index resulted in decreased swell potential and swelling pressure of the mixture.
Abstract: This study presents the effect of high plasticity on swell potential, swelling pressure and micro-structural characteristics of kaolinite-bentonite mixed clays. Five different mix ratios of kaolinite bentonite mixture of 100:0, 90:10, 75:25, 50:50 and 25:75 in % by weight of dry kaolinite were used. All five synthesised soils were then mixed with 0%, 5% and 8% of cement by weight of dry soil, cured for 28 days and subjected to the Atterberg limit, one-dimensional oedometer and scanning electron microscope test. The inclusion of 5% and 8% cement reduces the plasticity index of the treated soils as the percentage of bentonite increases. The effects on plasticity of treatment with 5% and 8% cement after a 28-day curing period was evaluated, and the results show that reduction in plasticity index resulted in decreased swell potential and swelling pressure of the kaolinite-bentonite mixed clays. The results of microstructural analysis of 5% cement-treated soils show formation of flocculated fabric and cementation of soil particles, and filling with cementitious compounds of the voids of flocculated fabric in the soil. The reduction in swell can be attributed to the resulting compacted and dense mass of treated soils due to cementation of soil particles and cation exchange. The complex swell behaviour of high-plasticity kaolinite-bentonite mix is explained using the one-dimensional oedometer test, by further experimental study and examination of the microstructure of treated soils.

36 citations

Journal ArticleDOI
TL;DR: In this paper, a detailed examination of the core mineralogy, microfabric, grain size and suction response of expansive clays during moisture ingress can be explained by an examination of their core mineralogical properties.
Abstract: The complex swelling mechanism in expansive clays during moisture ingress can be succinctly explained by an examination of their core mineralogy, microfabric, grain size and suction response. This note has attempted to investigate these influential factors on five different expansive clay samples to enable further understanding of swell behaviour. Laser diffractometry tests were performed on the expansive clays to determine the clay-sized particle structure (

28 citations

Journal ArticleDOI
TL;DR: In this article, the mechanical performances and water retention characteristics of clays, stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem (RC), are studied.
Abstract: The mechanical performances and water retention characteristics of clays, stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem (RC), are studied in this research. The unconfined compression tests and one-dimensional oedometer swelling were performed after 7 d of curing to understand the influence of addition of 1% of RC material in the stabilised soils with the cement partially replaced by 49%, 59% and 69% of ground granulated blast furnace slag (GBBS) or pulverised fuel ash (PFA). The moisture retention capacity of the stabilised clays was also explored using the soil-water retention curve (SWRC) from the measured suctions. Results confirmed an obvious effect of the use of RC with the obtained strength and swell properties of the stabilised clays suitable for road application at 50% replacement of cement. This outcome is associated with the in-depth and penetrating hydration of the cementitious materials by the RC and water which results in the production of needle-like matrix with interlocking filaments – a phenomenon referred to as the ‘wrapping’ effect. On the other hand, the SWRC used to describe the water holding capacity and corresponding swell mechanism of clays stabilised by a proportion of RC showed a satisfactory response. The moisture retention of the RC-modified clays was initially higher but reduced subsequently as the saturation level increased with decreasing suction. This phenomenon confirmed that clays stabilised by including the RC are water-proof in nature, thus ensuring reduced porosity and suction even at reduced water content. Overall, the stabilised clays with the combination of cement, GGBS and RC showed a better performance compared to those with the PFA included.

25 citations

Journal ArticleDOI
21 Jun 2020
TL;DR: In this paper, an experimental study was conducted to investigate the mechanical performance of polypropylene and glass fibre-reinforced cement-clay mixtures blended with ground granulated blast slag (GGBS), lime and micro silica for different mix compositions and curing conditions.
Abstract: Clayey soils endure adverse changes in strength and volume due to seasonal changes in moisture content and temperature It has been well recognised that high cement content has been successfully employed in improving the mechanical properties of clayey soils for geotechnical infrastructural purposes However, the environmental setbacks regarding the use of high cement content in soil reinforcement have necessitated the need for a greener soil reinforcement technique by incorporating industrial by-product materials and synthetic fibres with a reduced amount of cement content in soil-cement mixtures Therefore, this study presents an experimental study to investigate the mechanical performance of polypropylene and glass fibre-reinforced cement-clay mixtures blended with ground granulated blast slag (GGBS), lime and micro silica for different mix compositions and curing conditions The unconfined compressive strength, linear expansion and microstructural analysis of the reinforced soils have been studied The results show that an increase in polypropylene and glass fibre contents caused an increase in unconfined compressive strength but brought on the reduction of linear expansion of the investigated clay from 792% to 02% at fibre content up to 08% for cement-clay mixture reinforced with 5% Portland cement (PC) The use of 04–08% polypropylene and glass fibre contents in reinforcing cement-clay mixture at 5% cement content causes an increase in unconfined compressive strength (UCS) values above the minimum UCS target value according to American Society for Testing and Materials (ASTM) 4609 after 7 and 14 days curing at 20 °C to 50 °C temperature Therefore, this new clean production of fibre-reinforced cement-clay mixture blended with industrial by-product materials has great potential for a wide range of applications in subgrade reinforcement

23 citations


Cited by
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01 Jan 2000
TL;DR: In this article, a construction technique using the deep mixing method to reinforce the soft soil compound foundation, foundation pit support structure and the water cut off curtain is described, and the use of the SJC cement grout monitoring and recording system is introduced.
Abstract: The construction technique using the deep mixing method to reinforce the soft soil compound foundation, foundation pit support structure and the water cut off curtain is described. The use of the SJC cement grout monitoring and recording system is introduced.

67 citations

Journal ArticleDOI
TL;DR: In this article, the effect of different moisture conditions on the ductility, geotechnical and microstructural characteristics of the improved clayey subgrade with various lime contents and various moisture conditions was evaluated.
Abstract: This research evaluated the effect of different moisture conditions on the ductility, geotechnical and microstructural characteristics of the improved clayey subgrade with various lime contents and...

44 citations

Journal ArticleDOI
TL;DR: RoadCem (RC) is an additive produced based on nanotechnology and comprises of synthetic zeolites and alkali earth metals as some of its components as discussed by the authors, and the geotechnical properties of a soil stabilized by adding RC to partly replaced cementitious materials are studied.
Abstract: RoadCem (RC) is an additive produced based on nanotechnology and comprises of synthetic zeolites and alkali earth metals as some of its components. The geotechnical properties of a soil stabilized by adding RC to partly replaced cementitious materials are studied. Various combinations of the additives were investigated with the objective of reducing the amount of OPC by 50% by an inclusion of RC and ground granulated blast furnace slag (GGBS) in the stabilized soil. Laboratory studies involving index property testing, oedometer swell-deformation, unconfined compression tests and microstructural examinations were carried out on both the natural and 7-& 28- day cured samples of the stabilized soil. The influence of RC on the mechanical properties of the stabilized soil was examined by comparing the performance of the stabilized soil mixtures that contain the RC and the mixtures without the RC added. Results indicated the positive effect of RC as noticed by the tremendous strength gain in 7 days with the OPC reduced by 50% in the stabilized soil. Swelling decreased significantly to 0% after 28 days curing with the settlement also reasonably reduced for nearly all the percentages of the OPC substituted. The stabilized soil’s microstructure revealed the mechanism of cementation observed as an encapsulation or “wrapping effect” as a result of the presence of RC. A comparison of the RC-modified soil containing the by-products GGBS and PFA indicated that GGBS was more effective in the enhancement of engineering properties than PFA. Overall, as well as meeting some of the standards set for road pavement applications, the results obtained from this research are very promising for the ongoing discussions on reducing carbon foot-printing by OPC replacement.

42 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of high plasticity on swell potential, swelling pressure and micro-structural characteristics of kaolinite-bentonite mixed clays was presented, and the results showed that reduction in plasticity index resulted in decreased swell potential and swelling pressure of the mixture.
Abstract: This study presents the effect of high plasticity on swell potential, swelling pressure and micro-structural characteristics of kaolinite-bentonite mixed clays. Five different mix ratios of kaolinite bentonite mixture of 100:0, 90:10, 75:25, 50:50 and 25:75 in % by weight of dry kaolinite were used. All five synthesised soils were then mixed with 0%, 5% and 8% of cement by weight of dry soil, cured for 28 days and subjected to the Atterberg limit, one-dimensional oedometer and scanning electron microscope test. The inclusion of 5% and 8% cement reduces the plasticity index of the treated soils as the percentage of bentonite increases. The effects on plasticity of treatment with 5% and 8% cement after a 28-day curing period was evaluated, and the results show that reduction in plasticity index resulted in decreased swell potential and swelling pressure of the kaolinite-bentonite mixed clays. The results of microstructural analysis of 5% cement-treated soils show formation of flocculated fabric and cementation of soil particles, and filling with cementitious compounds of the voids of flocculated fabric in the soil. The reduction in swell can be attributed to the resulting compacted and dense mass of treated soils due to cementation of soil particles and cation exchange. The complex swell behaviour of high-plasticity kaolinite-bentonite mix is explained using the one-dimensional oedometer test, by further experimental study and examination of the microstructure of treated soils.

36 citations

Journal ArticleDOI
TL;DR: In this paper, a detailed examination of the core mineralogy, microfabric, grain size and suction response of expansive clays during moisture ingress can be explained by an examination of their core mineralogical properties.
Abstract: The complex swelling mechanism in expansive clays during moisture ingress can be succinctly explained by an examination of their core mineralogy, microfabric, grain size and suction response. This note has attempted to investigate these influential factors on five different expansive clay samples to enable further understanding of swell behaviour. Laser diffractometry tests were performed on the expansive clays to determine the clay-sized particle structure (

28 citations