The research program in transportation planning and operations is broadly focused in three areas:
- Travel behaviour research for developing countries
- Public transport – network and operational planning
- Access, mobility and exclusion
The use of new technologies and big data is a cross-cutting thread that runs across all three thematic areas.
Examples of recent work in these areas include:
Covid-19 and transport in South Africa
The CTD is currently doing research on changes in travel behaviour and transport sector performance as a result of the pandemic. Recent publications on the impacts of the Covid-19 pandemic on transport in SA include:
Designing effective transport systems in unequal societies
Transport planners in highly unequal societies such as South Africa face challenges in designing transport systems that meet the needs of diverse user groups. These include groups that are very price-sensitive, and those for whom fast and reliable services are more important. This leads to difficult trade-offs, for instance between investing in travel-time saving priority infrastructure such as Bus Rapid Transit systems, while keeping fares at affordable levels for the majority of poor users. Researchers are investigating effective ways of making these trade-offs, based on a better understanding of heterogeneity and segmentation within the user population.
The first/last mile connection to public transport
A component of the public transport trip that is often neglected is the first/last mile (1LM). This could be a walking or cycling trip, or taken by e-hailing or some other public transport mode. CTD researchers developed a systematic method for measuring the quality of the 1LM environment, across non-motorised and feeder bus modes, while taking the subjective priorities of passengers into account. The method was applied to both Gautrain and BRT systems in Gauteng.
In another project an online stated preference survey was used to collect data on the choice behaviour of Gautrain passengers for their access and egress modes. This was used to test the demand effects of various 1LM strategies, such as expanding bus routes or raising parking fees.
Priority infrastructure for informal modes in hybrid public transport networks
A number of research projects are looking at ways of better integrating minibus-taxis into a citywide public transport network, by doing things such as building special lanes for taxis, or implementing a common fare payment system using smart cards, or planning for easy transfers between vehicles. Computer models of such optimised networks have shown that significant benefits can accrue to both passengers (in terms of faster trips) and operators (in terms of faster turnaround times), and that a case can be made for reprioritising scarce road space in our cities towards public transport. Ongoing research is investigating the implications of rolling out priority lanes and infrastructure priority measures (such as queue jumping lanes) on a city-wide basis.
Accessibility as a participatory planning tool
CTD researchers have been collaborating with MIT to test a web-based, interactive approach to engage citizens in local planning of their transport solutions. The approach, named CoAXs (Collaborative Accessibility-Based Stakeholder Engagement for Public Transportation Planning) was tested during four workshops that were held in Pretoria during 2018. Similar workshops held in Bogota (Columbia) and Concepcion (Chile) have delivered insight into how collaborative techniques can be scaled up to provide wider impacts to communities during the planning process.
Mobility and access in African cities
African cities are making progress in investing in new fixed-route bus and rail systems, but still face major challenges in extending the benefits of access to all their residents. The CTD has recently co-authored a systematic review of the state of knowledge on public transport system design and modal integration, on behalf of VREF’s Mobility and Access in African Cities (MAC) programme. The report reviews current challenges and achievements in Sub-Saharan African cities. Download it here.