Development and implementation of risk-based maintenance management

To choose the most suitable maintenance measures, there is a need for criteria. In the past, the decision was always based on the structural condition, whereas risk-based maintenance management incorporates many other factors.



The Swiss Federal Railways (SBB) have several thousand bridges, requiring a comprehensive maintenance management system. The current maintenance management is based on their condition. However, the condition of a structure does not give any indication of its importance to the SBB network. The closure of one particular bridge may have little impact on the SBB network as a whole, whereas the loss of another may adversely affect all travel services nationwide. Risk-based maintenance management identifies such effects.

Course of action

The project was carried out in four stages. Firstly, a status report was produced to determine the level of information available. A risk-based procedure was then defined and implemented as a proof-of-concept. In a final stage, risk-based maintenance management was implemented technically in the form of programming for SBB. These steps were carried out for bridges. A proof-of-concept had previously been defined for supporting structures.


SBB has been using risk-based maintenance management for over a year. It is not the sole assessment tool used. It is deployed in conjunction with condition-based maintenance management. The procedure has proven useful in day-to-day activities.

Looking ahead

Work carried out so far only concerns risk assessment. Future activities may incorporate risk assessment into lifecycle costing or quality-of-life studies. Interestingly, SBB is a pioneer internationally in this field. Similar concepts are currently being discussed by the International Association for Bridge and Structural Engineering (IABSE). SBB is using the procedure developed in day-to-day activities in parallel with structural condition assessments.