Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
23 June 2021 | Story Leonie Bolleurs | Photo Supplied
The Department of Engineering Sciences (EnSci) – under the leadership of Dr Abdolhossein Naghizadeh – is heading a collaboration of scientists to create a green concrete that will reduce the impact of cement on the environment.

Conventional cement production is responsible for more than 6% of the overall carbon emissions in the world, which ultimately affects global warming.

The Department of Engineering Sciences (EnSci) at the University of the Free State (UFS) – under the leadership of Dr Abdolhossein Naghizadeh – is heading a collaboration of scientists from universities in South Africa and abroad to create a green concrete that will reduce the impact of cement on the environment.

This product has the potential to be used as an alternative to conventional concrete in large-scale constructions such as residential buildings and infrastructure, as well as small-scale constructions such a pavements and brickworks. 

Dr Nagizadeh, whose passion is cement and green concrete, says the idea of eco-friendly concrete was considered by European researchers a few years ago; however, this technology is still in its initial stages and has not been researched and employed at industrial scale yet. He believes that it is due to the complexity of the preparation process, and the relatively aggressive chemicals used in green concrete mixtures.

Expertise and equipment 

With his knowledge and experience of the product, Dr Naghizadeh – who joined EnSci in 2020 – has been appointed project leader of a collaborative group of scientists from the Universities of Johannesburg, KwaZulu-Natal, Yaoundé in Cameroon, and the Erzurum Technical University in Turkey.  

“Since there are only a limited number of researchers in this field, EnSci is benefiting from the expertise of this international collaboration. The proficiency of this group of scientists are keeping the project current, based on the latest findings in the research area,” says Louis Lagrange, Head of the Department of Engineering Sciences. 

Based on this new capacity, the department decided to establish and equip a new laboratory facility dedicated to cement and concrete research, with a specific current focus on green concrete. 

In this laboratory, they want to create formulations of green concrete, based on user-friendly materials. Furthermore, they aim to simplify the preparation and mixing process. “This can introduce a more eco-friendly, desirable product that can easily be employed extensively in the construction industry,” says Lagrange.

Benefits and other advantages

Besides its ability to reduce the impact on the environment through reduced carbon emissions, the product is also described to perform at equal or even superior strength and durability compared to conventional concrete, with potentially substantial environmental and economic benefits. 

This product is also primarily made from waste materials or industrial by-products. Dr Naghizadeh explains it as follows: “Normal concrete consists of conventional (Portland) cement, sand, stone and water, while in green concrete the conventional cement part of the concrete mix is replaced by industrial wastes or by-products and alkali solutions. These alternative materials are mostly aluminosilicate materials such as fly ash (residue from coal burning process in power plants) and slag (waste material from iron extraction processes).”

“Using these waste substances as binding material in green concrete can, apart from the environmental benefits, also reduce waste and contribute to the circular economy. Annually, more than 36 million tons of fly ash are produced in South Africa alone, of which more than 90% is deposited at landfill sites. Reuse of these waste materials will moderate the related waste deposition issues, such as air and groundwater pollution.”

Production of green concrete

Currently, green concrete is mostly produced in two parts: a solid raw material and an alkali activation solution. With their project, the research group wants to develop green concrete in a powdered form, to be mixed with water, instead of a chemical. Dr Nagizadeh estimates that the construction industry will be able to benefit from their work in about two years’ time when they will have a user-friendly green concrete product ready. 

Apart from putting an eco-friendlier concrete on the market, this project is also establishing a brand-new research niche in the UFS Department of Engineering Sciences. According to Lagrange, this research has the ability to attract postgraduate students and other researchers. He is also looking forward to the international academic recognition that EnSci will receive through published articles in leading international journals, and the participation of researchers in accredited conferences arising from this project. 

Lagrange is pleased that the project is establishing EnSci as a research player of note in the engineering field, specifically in the green engineering field. 

News Archive

Studies to reveal correlation between terrain, energy use, and giraffe locomotion
2016-11-18



More than half of giraffes in captivity in Europe are afflicted by lameness. This high prevalence represents an important welfare issue, similar to other large zoo animals.

According to Dr Chris Basu, a veterinarian at the Royal Veterinary College in the UK, giraffes in captivity are often afflicted by overgrown hooves, laminitis and joint problems. Diagnosis and treatment is limited by our understanding of anatomy and function, more specifically the locomotion of these animals. Although the giraffe is such a well-known and iconic animal, relatively little has been studied about their locomotor behaviour.

Dr Basu recently visited South Africa to do fieldwork on the locomotion of giraffes as part of his PhD studies under the mentorship of world-renowned Professor of Evolutionary Biomechanics, Prof John Hutchinson. This project is a joint venture between Dr Basu and Dr Francois Deacon, researcher in the Department of Animal, Wildlife, and Grassland Sciences at the UFS. Dr Deacon is a specialist in giraffe habitat-related research. 

Together Prof Hutchinson and Drs Deacon and Basu form a research group, working on studies about giraffe locomotion.

Wild giraffe population decrease by 40% in past decade

“Locomotion is one of the most common animal behaviours and comes with a significant daily energetic cost. Studying locomotion of wild animals aids us in making estimates of this energetic cost. Such estimates are useful in understanding how giraffes fit into ecosystems. Future conservation efforts will be influenced by knowledge of the energy demands in giraffes.

“Understanding aspects of giraffe locomotion also helps us to understand the relationships between anatomy, function and evolution. This is relevant to our basic understanding of the natural world, as well as to conservation and veterinary issues,” said Dr Deacon.

Locomotion study brings strategy for specialist foot care

On face value it seems as if foot disease pathologies are more common in zoo giraffes than in wild giraffes. “However, we need a good sample of data from both populations to prove this assumption,” said Dr Basu. 

This phenomenon is not well understood at the moment, but it’s thought that diet, substrate (e.g. concrete, straw, sand and grass) and genetics play a part in foot disease in giraffes. “Understanding how the feet are mechanically loaded during common activities (standing, walking, running) gives our research group ideas of where the highest strains occur, and later how these can be reduced through corrective foot trimming,” said Dr Basu.

Through the studies on giraffe locomotion, the research group plans to devise strategies for corrective foot trimming. At the moment, foot trimming is done with the best evidence available, which is extrapolation from closely related animals such as cattle. “But we know that giraffes’ specialist anatomy will likely demand specialist foot care,” Dr Basu said.

Studying giraffes in smaller versus larger spaces

The research group has begun to study the biomechanics of giraffe walking by looking at the kinematics (the movement) and the kinetics (the forces involved in movement) during walking strides. For this he studied adult giraffes at three zoological parks in the UK. 

However, due to the close proximity of fencing and buildings, it is not practical to study fast speeds in a zoo setting. 

A setting such as the Willem Pretorius Nature Reserve, near Ventersburg in the Free State, Kwaggafontein Nature Reserve, near Colesberg in the Karoo, and the Woodland Hills Wildlife Estate in Bloemfontein are all ideal for studying crucial aspects such as “faster than walking” speeds and gaits to measure key parameters (such as stride length, step frequency and stride duration). These studies are important to understand how giraffe form and function are adapted to their full range of locomotor behaviours. It also helps to comprehend the limits on athletic capacity in giraffes and how these compare to other animals. 

Drones open up unique opportunities for studying giraffes

The increasing availability of unmanned aerial vehicles (UAVs)/drones opens up unique opportunities for studying locomotion in animals like giraffes. Cameras mounted onto remotely controlled UAVs are a straightforward way to obtain high-quality video footage of giraffes while they run at different speeds.

“Using two UAVs, we have collected high definition slow motion video footage of galloping giraffes from three locations in the Free State. We have also collected detailed information about the terrain that the giraffes walked and ran across. From this we have created 3D maps of the ground. These maps will be used to examine the preferred terrain types for giraffes, and to see how different terrains affect their locomotion and energy use,” said Dr Deacon.

“The raw data (videos) will be digitised to obtain the stride parameters and limb angles of the animals. Later this will be combined with anatomical data and an estimation of limb forces to estimate the power output of the limbs and how that changes between different terrains,” said Dr Basu.


Related articles:

23 August 2016: Research on locomotion of giraffes valuable for conservation of this species
9 March 2016:Giraffe research broadcast on National Geographic channel
18 Sept 2015 Researchers reach out across continents in giraffe research
29 May 2015: Researchers international leaders in satellite tracking in the wildlife environment

 

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept