A synchromodal transport network is a transportation technique which aims to create more efficient and sustainable transportation plans, which utilizes different modes of transport, i.e., roadways, railways, and waterways synchronously. Synchromodal transport network is a complex network with interdependence. The aim of this thesis was to analyze the robustness and identify critical infrastructure in synchromodal transport network. In order to achieve the goal of the thesis. First, the synchromodal transport network is analyzed on the basis of its transportation characteristics and network topology. The analysis of transportation characteristics helped us to define a notion of node criticality. The node criticality quantifies the effect on the robustness of a transportation system due to the perturbation of an infrastructure. Then, a relationship is established between the node criticality and topological centrality metrics in order to quickly identify critical infrastructures in the synchromodal transport network. Lastly, a systematic framework is proposed and applied to the Dutch synchromodal transport network. The results from the case study are quite insightful. First, we observe that the distribution of node criticality exhibits a power-law distribution which implies that the Dutch synchromodal transport network tends to robustness against node perturbation. Second, we observe that the performance of the dutch synchromodal transport network is quite sensitive to the perturbation in the road network. Lastly, we identify that the weighted degree centrality, eigenvector centrality shows a high correlation with node criticality thus these centrality metrics can be used to identify critical infrastructure in the synchromodal transport network.

Freight transport is an essential component of the economy, as among other things it ensures the availability of finished goods to consumers. Synchromodal transport is a new transport method that aims to use real-time and flexible switching among different modes of transport according to the latest logistics information, to utilise the different modes of transport efficiently. But what are the effects of disruptions of the infrastructure used by synchromodal transport on freight transport? As some recent disruptions in the Netherlands have shown, the negative effects can be considerable. The effects of disruptions on the functioning of multimodal transport networks have scarcely been researched. This research gap is addressed in this thesis, by analysing the robustness of the Dutch synchromodal freight network, comprising of the inland waterway, road, railway and container terminal infrastructure.

First an overview is given of the elements of the synchromodal transport infrastructure. Apart from the infrastructure elements of each mode of transport, two important characteristics are identified: the interconnection and the interdependence. Container terminals are the interconnection between different modes of transport, as they facilitate the transshipment of containers. Infrastructure elements whose functioning influences multiple modes of transport (e.g. bridges) are the interdependence between different modes of transport. Subsequently, this overview of infrastructure elements is used to make a macroscopic graph model in which all relevant infrastructure elements are represented. Using the random removal of graph elements, the robustness of the synchromodal network is analysed. Three case studies are used to study the Dutch synchromodal network: the corridor between Rotterdam and Antwerp, the corridor Rotterdam and Duisburg, and the domestic freight transport in the Netherlands.

The robustness analysis of the three case studies lead to the following conclusions. Of the three modes of transport, the modality road is the most robust. The inland waterway modality is less robust and the rail modality is the least robust. It should be noted that the rail modality provides a relatively cheap alternative and offers the capabilities to transport containers further into Europe than the inland waterways. The ability to transship containers between different modes of transport (i.e. interconnection) has a significant positive effect on the robustness. The interdependence has a smaller negative effect on the robustness. Generally, the new alternative paths offered by the addition of a mode of transport (even without interconnection) outweigh the negative effects of the interdependence.

These findings make it clear that the use of the synchromodal transport method, increases the robustness of the freight transport network. During this research, many possibilities for future research were identified. As the research gap for analysing the robustness of a synchromodal transport network was very large at the start of this research, many things can still be researched after this research. The importance of freight transport warrants additional research on this topic. According to this research, due to mode-free booking and the real-time and flexible switching among different modalities, synchromodal transport offers a robust freight transport method.