jan husdal instr 2004

8/14/2019 Jan Husdal INSTR 2004

1/13


2/13

Objective Why (and how) should we apply

vulnerability (and reliability) in cost-benefit evaluations or projectevaluations in general?

3 fields are brought together: engineering (reliability and vulnerability) economics (costs and benefits) politics (decision- making)


3/13

Contentions Additional travel costs incur when

persons, travellers or goods do notreach their destination in space ortime as intended.

Reliability Benefit

Vulnerability... Cost


4/13

Rationale To add reliability and vulnerability to the

traditional equations of costs and benefits. So that transport planners and

professionals not only consider economicalarguments, but also dare to take onpolitical statements.

To allow these statements to be inopposition to the factual costs and benefitsof a project (as prescribed by currentevaluation methods).


5/13

Vulnerability vs. Reliability Reliability

Probability Predictability Maintaining a link (or a system)

Vulnerability

Susceptibility Impact (system-wide) Disrupting a link


6/13

Vulnerability vs. Reliability A reliable network:

Exhibits a high degree of operability(serviceability, accessibility, non-variability)under any circumstance

A vulnerable network: Exhibits a low degree of operability under

certain (usually external) circumstances

Vulnerability = Non-Reliability(under said circumstances)


7/13

Vulnerability vs. Risk R = P x C

R = Risk P = Probability C = Consequence

V = S x I V = Vulnerability S = Susceptibility to

operational degradation, I = Impact (cost) of

degradationVulnerability matrix.

The threshold indicates thevulnerability acceptance level


8/13

Attributes of vulnerability

Road networks are vulnerable to 3 influences: structure-related,nature-related and traffic-related. It is the collective sum of thesevulnerabilities that needs to be addressed.


9/13

The cost of vulnerability

The societal costs of vulnerability versus reliability. A - current state, B high investment

(new road), C low investment (upgrading existing road), D - optimum


10/13

Future research Establish a practice-oriented methodology

for aggregating a vulnerability index for aroad network, pertaining to attributes ofstructure, nature and traffic.

Integrate vulnerability into the quantitativeand qualitative framework of cost-benefitanalyses used in the transport sector.

Apply vulnerability as a decision variable inthe evaluation process for new roaddevelopments.


11/13

The service area of the hospitals in Molde and Kristiansund, onthe north-western coast of Norway, is marked by a number ofpotential vulnerabilities: F=Ferry, CW=Causeway, ST= SubseaTunnel, T=Tunnel, M=Mountain Pass, B=Bridge


12/13

Current research in Norway The transport sector in

general has very limited

experience with regard torisk based management

Cost-benefit analyses andenvironmental impact

analyses are being used, butrisk analyses and riskacceptance criteria are not.

Risk as a concept and as amanagement tool has nomarked tradition among theNorwegian road authoritiesor amongst the internationalroad authorities

(Aven, 2004)


13/13

Thank you

jan husdal instr 2004

Documents