Building Blocks for Practical Quantitative Risk Assessment

The webinar will review the basic building blocks for performing quantitative risk analysis related to dam safety and how they fit into the spectrum of risk assessment.  Several potential failure modes will be discussed along the way to illustrate the concepts and how they fit together. 

 Topics will include:

• Brainstorming and initial screening of potential failure modes
• Potential Failure Mode Identification – This is the first vital step for any risk assessment.
• Semi-quantitative risk assessment for additional screening of potential failure modes.   Since there is a 3-day training class available through USSD for this, only a brief description will be presented, but criteria for deciding which potential failure modes to carry forward to quantitative risk analysis will be discussed.
• Event Trees – The rules for constructing event trees from potential failure mode descriptions and for estimating probabilities will be discussed.
• Load-Frequency Analysis – Determining load probabilities from seismic hazard curves, hydrologic hazard curves, and reservoir frequency curves will be discussed.
• Probabilistic Analyses and Models – The mechanics of performing probabilistic analyses will be discussed.
• Frequency Data – Sometimes statistical data can be used to make some judgments about probabilities.
• Subjective Probability and Expert Elicitation –The procedures for conducting expert elicitation to obtain probabilities, and some of the biases to be aware of, will be presented.
• Consequences – Consequences represent one third of the risk equation.  Estimating consequences, focusing primarily on life safety, will be briefly discussed.
• Tolerable Risk Guidelines and Building the Case – How the building blocks fit together and building the case for whether the estimates meet tolerable risk guidelines will be discussed.

Audience 

The webinar is geared toward people of various disciplines and experience levels working in the area of dam safety.  A basic understanding of dams and appurtenant structures, as well as traditional dam safety evaluations will be useful in understanding the information presented.

2 CEUs