Ranging from the use of tablets and web-based applications for slope assessments along our national routes, to the use of virtual reality to view site survey information in 3D, these digital tools are both practically useful and exciting.
Rock cuts at Ecca Pass, on the R67 north of Grahamstown, were assessed using the Aurecon Forms App
Aurecon South Africa has been appointed by the South African National Roads Agency SOC Ltd (SANRAL) to provide geotechnical engineering services for its Western and Southern Regions. This includes assessment of all the cuts and fills higher than 5 m along the national and some regional routes in the Western, Northern and Eastern Cape, which add up to a total of more than 3150 slopes – a monumental task. The evaluation and rating system (SANRAL Slope Management System) used to assess these slopes is based on work done by Hall and Knottenbelt (1992), and further refined by SANRAL. This rating system is summarised on a form that is completed following a visual inspection of each slope. Before the advent of smart devices and web applications, this work would have involved much paper work, manual input of data and a long lead time before any information would have been available for review.
Although not new technology, Aurecon developed a web-based application called Aurecon Forms to speed up the process. The Aurecon Forms App allows the user to input the slope assessment data into a tablet or smartphone, record the GPS location, take photographs and record voice notes. Perhaps the most useful part of this application is that the assessment can be uploaded immediately from the field for review in the office. This improves the technical quality and efficiency of the work because queries can be addressed almost immediately, while the site inspection is still fresh in the memories of the inspectors. When accessing the application from a web browser in the office, the map view gives the user a general picture of the assessed slopes, which are colour-coded according to their ratings.
Aurecon Forms viewed through a web browser
Users are able to easily filter the data, enabling them to view specific routes or sections. Once approved, the individual reports are generated and exported as PDFs by the click of a button. Other benefits include the ability to track the progress of the work as multiple teams are uploading inspection reports, and a client viewer that allows the client to see the progress of the work in the field. The application allows the user to view the location of the slope in Google Earth and access Google Street View, which immediately gives the reviewer an appreciation of how the slope may have degraded over time.
A slope assessment for an individual slope
The use of virtual reality (VR) in civil engineering may seem like a strange concept, but it promises to have some unexpected benefits. Aurecon is currently exploring the potential of this technology for use in the design and review process. Survey data is processed and digitised to build a 3D model. The model is then updated with all the relevant information as the project progresses. This will include the survey information, existing infrastructure and information from the site investigation, as well as moving animations (such as cars moving along the highway). This virtual world is not meant to replace a site visit, but it is used to help develop our understanding of the site by being immersed in the digital model. The model can be updated with planned new infrastructure as a design review and collaborative tool.
Trevor Pape in Aurecon Cape Town’s VR room
Similar to virtual reality, augmented reality (AR) offers opportunities for collaborative design and review. It is technology that superimposes a computer-generated image on the user’s view of the world. If multiple users are wearing AR goggles it would enable them to view the same computer-generated image at the same time. For example, if that computer-generated image is a proposed design, it would enable professionals to collaboratively review the design in 3D.
A particularly interesting application of this technology is the geological mapping of steep rock slopes that would otherwise only be accessible with rock climbing equipment. This process involves the use of drones and photogrammetry to survey and photograph the rock slope in high definition. The photographs are then overlaid onto the survey data and an accurate 3D model is created. Viewing this 3D model, together with other professionals in AR, enables up-close inspection of joints, bedding planes and rock masses that would otherwise have been difficult to access. Proposed infrastructure can then be added to the model and reviewed in 3D.
Great advancements have been made in recent years in both the fields of computer gaming and engineering modelling. One may think that these fields are not related, but there could be some synergies. In an effort to create more realistic games, computer programmers have incorporated physics into their gaming code. Now the question arises: Would it not be possible to use computer gaming engines to simulate engineering problems? Although not yet applied to advanced geotechnical problems, it is possible to simulate a rock falling down a slope in 3D. It will be interesting to see what digital design tools eventually emerge from the fusion of these seemingly unrelated fields.
The modern world we live in is abounding with new ideas and interesting technology and it is a continual journey to discover how we can apply these digital tools to our advantage. The use of tablets and web-based applications has facilitated the assessment of a large number of slopes. VR and AR promise to become powerful tools for geotechnical design and review. As we look to the future, let us keep an open mind as we find new applications for the plethora of smart technology around us.
Digital overload, AR in the foreground and VR in the background
The work referred to in this article is being carried out for the South African National Roads Agency SOC Limited. The content of the article reflects the views of the authors who are responsible for the facts and accuracy of the data presented herein. The content does not necessarily reflect the official view or policies of the South African National Roads Agency SOC Limited. Their permission to publish the article is gratefully acknowledged.
Hall & Knottenbelt (1992). Towards a slope management system for roads. Proceedings, Annual Transportation Convention, Pretoria.
This article was originally published in the Civil Engineering Magazine of the South African Institution of Civil Engineering.