Abstract:
Transportation research and development covers a multitude of topics regarding all
areas in transportation. Transportation reliability and vulnerability studies are a new
area that has started to draw a lot of attention particularly about its possible
applications to help disaster management practices. But unfortunately transportation
network risk and vulnerability assessment has not received due recognition so far
when formulating preparedness policies in disaster management operations. There are
various types of studies such as environmental impact assessment, cost benefit studies
for transportation infrastructure where a wide variety of features are looked at, but risk
and vulnerability analysis of the transportation network has not yet been considered
with much importance. One major reason for this can be highlighted as the lack of
established terminology and associated means of analysis that can be specifically
adopted for the purpose. And further more it is difficult to draw a firm consensus on
available methods due to various disparities among the concepts proposed.
The aim of this research is to develop a methodology to evaluate the state of
transportation networks in terms of accessibility and connectivity under disaster
situations. A new methodology is proposed based on concepts of both vulnerability
and reliability assessment of transportation networks. The proposed method expresses
the state of the network using an index defined as the Preparedness Index that is used
as a measurement of the state of the network against possible threats and degradation
due to damage.
The proposed preparedness index has two components, one to assess the quality or
the effectiveness of the connection in terms of distance covered, travel time or LOS
provided, and the other component to assess the probability of maintaining the
connection that takes in to account the prevailing uncertainty in the network. With the
proposed concept it was possible to achieve a good balance in the measurement
regarding the state of the network without any one component, either network
structural aspects or predictability and probability aspects dominating the analysis.
Therefore this proposed index has the potential to over come some of the draw backs
identified with conventional methods.
