Probabilistics is a methodology for dealing with uncertainty in calculations. It is a core area of expertise for TNO and we apply it in our research on various safety issues. We use probabilistic methods in areas including disaster impact, pharmaceutical safety and the risks of industrial activities. We also apply this expertise in research on the built environment.
In the field of the built environment, TNO applies advanced probabilistic methods to:
In most instances there are few cases available for calculating the probability (which is usually low) of failure, such as collapse and flooding. Safety can be assessed with tests (including scale tests) in a controlled environment (laboratory). These tests are the basis for physical models, which are used to simulate reality. Safety can therefore be determined arithmetically. Probabilistic techniques can be used to shorten computing time for statistical analyses. The techniques can be combined with knowledge of the situation to accurately determine and show failure probability and the consequences of failure. There are no standard calculation models available for safety assessment in complex projects and situations. The experts at TNO carry out calculations that are tailored to the specific situation. They make customised models and identify uncertainties and their effect on safety.
The management and maintenance of structures is increasingly based on assessing risks and prioritising. Due to the growing number of structures, choices need to be made in terms of whether repair and replacement work is necessary or desirable (probabilistic management and maintenance). Inspection frequency can be optimised by comparing the results of different inspections. Higher-risk, older structures may need to be inspected more often, while new structures may not need to be inspected for the time being, or only on an ad-hoc basis. Older structures that have never shown deficiencies will probably remain safe for a number of years.