Microsoft Excel©-based tool for the risk analysis of rockfall protection galleries
Clients: ASTRA, Federal Road Authorities, Switzerland
Project partners: ETH Zurich; PRA Ingenieurs Conseils SA
In the present project, a generic and probabilistic model is developed for the purpose to assess the risks due to rockfalls on rockfall protection galleries, considering site and object-specific characteristics of galleries, slope and geology of the sites surrounding the galleries, and traffic profile of roadway under the galleries as indicators. In order to assess the risks due to rockfalls, a close collaboration between geologists and engineers is required. The collaboration enables that the rockfall process and potential risks associated with rockfalls are modeled in an integrated manner; the detachment process of stones, falling process, structural failures of galleries and consequences due to the failures are modeled explicitly and individually. The probabilistic models thus developed are represented in terms of Bayesian probabilistic networks.
The project is requested to ensure practical applicability, consistency, homogeneity and comparability of the assessment results from the software tool. To meet these criteria, the developed models are implemented into Microsoft Excel®-based software tool; using the indicators, which are typically available and defined a-priori, as input to the software tool, the tool calculates risks - not only mean values of consequences but also their distributions; risks in aggregated manners as well as individual risks for different types of consequences such as property damages and fatalities. Since the risk analysis is performed background, the use of the software tool requires little expertise of probability concept.
Note that the present project is addressed as a flagship project to illustrate how generic probabilistic modeling approach works for relevant decision situations in engineering.
RiskNow - Falling Rocks benefits:
- Falling Rocks facilitates fast and efficient risk assessment on rockfall protection galleries.
- Falling Rocks considers all relevant site and object-specific characteristics as indicators.
- Falling Rocks calculates the failure probability of rockfall protection galleries explicitly.
- Falling Rocks calculates individual risks for different types of consequence.
- Falling Rocks requires no professional knowledge on probabilistic modeling.
- Falling Rocks is Microsoft-Excel©-based and thus can incorpolate its standard functions.
- Falling Rocks establishes a general framework for risk assessments for gravitational natural hazards.