Why does CiviLab@CUT exist?

CiviLab@CUT started as part of the Soil Mechanics Research Group (SMRG) and was initially set up to address the problem of damage to light structures (particularly RDP houses) caused by founding on expansive soil. This is a widespread problem in the semi-arid area of Central South Africa. Since then, however, CiviLab@CUT has expanded into the industry conducting research in road repairs, concrete testing and maintenance, we have continued our research in soil testing and are moving deeper into determining the effects of expansive soils on structures. Along with our testing, we are developing a database of tests we have conducted that will make this information available to a broader group of engineers, allowing faster and easier transfer of information between professionals in the field.

Our Projects

Road works

The Community Engagement (CE) program was facilitated by CiviLab@CUT in collaboration with CUT Innovation Services (CUTis), and the Tokologo Local Municipality (Department of Roads). The project was applied research where the viability of a new advanced cold asphalt mix was investigated during a road maintenance project within the Tokologo Local Municipality. This project was started and completed in 2021.

Over the past five years, Tokologo Municipality experienced a backlog in the maintenance of road infrastructure, particularly in road surface maintenance. This subsequently has led to road asphalt surfacing within the municipality to be in very poor condition leading to the formation of potholes. The problem was also a result of a lack of technical skills to adequately perform quality repairs and monitor road defects. The municipality engaged with the CUTis to investigate socio-economic solutions to this problem. CUTis, in collaboration with CiviLab@CUT, presented a new technology called the Road-Safe Pothole Repair product (RSPR) to the municipality. The proposal was accepted, and the project started on 13 September 2021.

This project aimed to enhance sustainable community engagement activities while promoting socio-economic benefits while implementing social and technological innovations. This project brought value to teaching and learning, research and innovation and contributed to the development of graduate attributes. The CE project also positively impacted job creation and skills development and is highlighted in the following sections.

Over the past few years, the development of potholes in South African roads has accelerated considerably, leading to serious concern and comprehensive media coverage. The increase in pothole damage can be attributed primarily to reduced preventative maintenance applied to many roads, combined with particularly wet periods during rainy seasons and rapidly increasing numbers of heavy vehicles. The actual costs of potholes in South Africa in terms of damage to vehicles and accidents caused directly by potholes, and other road-user effects probably run into billions of rand, as suggested by media publications.

The main objective of this CE project was to implement a concept that has positive, sustainable, and measurable benefits for the communities as well as the industry involved in the project, thus creating shared value such as prospering societies and sustainable livelihood. Skills, passion, and hard work were invested in helping the two affected communities to improve their lives through this maintenance road project. The basic principles of pothole repair were shared with the local labourers provided by EPWP (Expanded Public Works Program) in the towns of Boshoff and Hertzogville. They all received signed certificates for their training and participation to enhance their chances for future work opportunities. The practical lessons covered were as listed:

• Cleaning road surface
• Cutting, excavating, and cleaning cut road surface excavation
• Filling and levelling patch material
• Compaction with vibrating plate compactors and vibrating roller compactors
• Traffic diversion

The Road works project management team. From left (back row): Jonathan Steenkamp, Elias Chakane, Socrates Toolo, and Malelo Mweemba.
From left (front row): Boitumelo Thlakung, Prof. Elizabeth Theron, and Boitumelo Sehularo.

Concrete

We are currently investigating two products from Penetron. The first product is called Penetron Cystalline Waterproofing Coating:

• When Penetron Cystalline Waterproofing Coating is applied to a concrete surface, the active chemicals react with moisture and the by-products of cement hydration to cause a catalytic reaction that generates an insoluble, crystalline structure. These crystals fill the pores and minor shrinkage cracks in the concrete to prevent further water ingress (even under pressure).
• In addition to waterproofing the structure, the product protects concrete against seawater, wastewater, aggressive groundwater, and other aggressive chemical solutions. This product is approved for use in contact with potable water and is therefore suitable for use in water storage tanks, reservoirs, water treatment plants, etc.
• The study's goal is to examine the product's validity by using Penetron's product after the Alkali-Silica Reaction has taken place. The results we anticipate will either repair the harm ASR has done to concrete or prevent the hydroscopic gel from absorbing more water, preventing the concrete from swelling and preserving its mechanical qualities. Creating construction industry standards would serve as the other goal while performing concrete maintenance or repairs. Providing a set solution or rules that construction companies must abide by.

The second product is called Penetron Admix Crystalline Waterproofing Admixture:

• When mixing the concrete, Penetron Admix (an integrated crystalline waterproofing admix) is added. Portland cement and numerous active, patented additives make up Penetron Admix. These active chemicals catalyse a reaction that results in a non-soluble crystalline formation throughout the pores and capillary tracts of the concrete because of the reaction between the moisture in freshly laid concrete and the by-products of cement hydration. As a result, the concrete is permanently protected from the seepage of liquids or water from any angle. Additionally, the concrete is shielded from environmental damage that could cause it to deteriorate.
• The goal of this study is to examine if the statements that keep water from penetrating concrete and stopping ASR from ever occurring are true. This is because calcium silicate hydrate cannot absorb more water than the initial mix. To enforce the standard to be utilised and avoid subpar concrete construction, a standard should be set by a professional group, such as South African National Standards.

Soil Testing

CiviLab@CUT has been working on procedures for assessing the suction potential of soils quickly, efficiently and economically. These procedures not only appear to give good estimates of heave potential but also of variability. Comparisons between soils from construction projects which have failed and others which have not failed suggest that variability is a very significant contributor to failure.

CiviLab@CUT is also looking into addressing the problem of heave damage by combining structural and geotechnical design. The standard method of solving the problem of heave damage is to provide a foundation stiff enough to limit distortions imposed on the superstructure to minimal values. This may require raft foundations with deep and heavily reinforced stiffening beams.

A more economical solution may be to use mortar which is flexible enough to allow significant distortion in the masonry before cracking. This flexibility needs to be combined with sufficient bonding strength to the masonry units to limit the separation of bricks from the mortar. Unfortunately, the quality of masonry in South Africa has reached a very low level. Over-attention to minimising cost has led to abysmal standards of brickwork in general and mortar in particular.

Tests at the SMRG have found that practically none of the sand currently used for masonry in the Free State comes close to meeting the water-demand requirements of the masonry code. Hence, they cannot even produce mortar with an acceptable water-cement ratio. SMRG is working on a mortar mix design that can meet the requirements of the masonry code, give good bond strength and flexibility, and be integrated with geotechnical design to optimise the solution to the problem of heave damage.

Development of a geotechnical engineering database

A comparison study was done to assess the existing information systems and determine whether the needs of South African engineers were being met. The database was then conceptualised and created with a primary focus on SANS3001 standards. Database tables were designed and developed for each of the standard SANS3001 geotechnical engineering tests, advanced geotechnical tests and test pit profiles. These tables were linked to a primary table that contained all the critical data for the layer of the test pit from which it originated. The database functions as a system where data can be managed and stored, allowing engineers to compare all relevant site and laboratory information during desktop studies to improve their decision making.

Reason For Designing A Database

A desktop study is an initial study performed by a geotechnical engineer before a site investigation and more detailed geotechnical investigations are executed. A desktop study is a relatively inexpensive method for providing an initial understanding of the site, identifying potential risks, and mapping any relevant geotechnical data from previous construction works on and around the site.

However, finding information from previous sites could be challenging, especially in South Africa, where no database systems have been established to capture this data for open access to all geotechnical engineers in South Africa. The CiviLab@CUT is developing a Database for Geotechnical Engineers (DGE) that could eventually be accessed by all geotechnical engineers and allow these engineers to share data and improve the quality of desktop studies and site investigations. Databases are organised collections of data stored and accessed electronically through a computer system. They must be designed correctly before they are created, as poor design could lead to failures or significant problems in the database itself. To make good decisions, one requires good information derived from raw facts.

In this way, data is managed more efficiently in databases. The difference between data and information is that data is raw facts that have not been processed, whereas information results from processing the raw data to reveal meaning. This processing could be as simple as revealing patterns or as complex as making forecasts.

This information could be used as the basis for decision-making. Raw data should be appropriately formatted for storage, processing, and presentation. During site investigations, samples are collected for geotechnical laboratory tests. These tests are essential for assessing soil engineering properties under controlled conditions. Some of these are index tests that help to classify and identify the soil. Other performance tests help engineers estimate soil engineering properties for analysis and design (De, 2015).

The results from these tests work well with the site investigation information to give a geotechnical engineer a good impression of the soil conditions on a site. Therefore, these tests were included in the database. The tests, however, must strictly follow the SANS3001 codes, which are standard in South Africa. SABS provides a range of standards covering the civil engineering industry requirements, from quality management systems to testing methods for specific materials or parts. SANS3001 refers to standards that test materials required for civil engineering practice. As the SANS3001 series of test methods are published, they supersede the previously used TMH1 methods (South African National Roads Agency, 2013).

With the DGE, data can now be stored and transformed for decision-making. The literature review about available information systems provided much-needed information about the current systems used and the availability of these systems for South African engineers. During this study, it became clear that an information system should be put into place to assist with the effective management of data that has spatial information.

The system should transform the data into the required outputs of the tests (especially SANS3001 standard tests) and give important engineering insight that assists decision-making. Unfortunately, the available systems do not provide much assistance to decision-makers, especially in a South African context. For this reason, the DGE was created for engineers to store, manage, and compare relative geotechnical engineering information. The next stage for the DGE will be building a network of laboratories and engineers to contribute data to the database and share the information with all professionals in South Africa.

Our Team

Prof. E Theron | Mr S.G. Water | Mr J.D. Steenkamp

Mr M. Mweemba | Mr D. van Wyk | Mr S. Toolo | Ms B. Sehularo

Mr L. Kikine | Mr. I.Y. Glynos | Ms B. Tlhakung