There is an increasing focus on risk and reliability assessment to be the basis for design, inspection and maintenance of engineered structures. As part of DNV Software’s strategic R&D effort, the Risk Framework development aims at providing seamless integration for software assisting Risk Based Inspection (RBI) programmes.

To support this task, there is a need for predictive calculation of probabilities based on actual statistics and state-of-theart modelling of relevant failure modes to be integrated into the Risk Framework.

The DNV Software program Proban was designed to solve DNV’s need for such calculation. It provides the ssystem modelling and statistical modelling required. It has more than 20 standard distribution types, and permits correlation and extreme value modelling. The user models the required failure functions. A variety of methods, analytic methods as well as sampling methods provides analysis results in terms of:

• Probability/Reliability Index
• Crossing rate
• First passage probability
• Distribution
• Importance of uncertainty
• Parametric sensitivity

A part of DNV Software’s R&D effort is therefore to provide integration of Proban into the Risk Framework. As Proban was developed 20 years ago, the GUI and database technology employed is obsolete; a major revision was required. As the Proban modelling and methodology is already well developed, the focus of the upgrade is on developing a new GUI, and to provide the program as a set of modules making integration with application software as simple as possible.

The tasks are as follows:

• Implement Proban GUI and data storage using .NET technology
• Provide the Proban computational core as executables
• Provide distribution fit as a separate program
• Provide a protocol for easy communication with other software, XML.

The new GUI implements are:

• Libraries for storage/reuse of all modelling
• Top-down modelling of events and models (variables)
• More intuitive input
• User-coded functions in GUI
• Configurable dialogues
• Results viewer as a separate module.

The new Proban adds value to the Risk Framework. The program may be referenced from any program implementing software for reading to/from the protocol file. It may similarly reference any package for function calculation by implementing software for writing the function value into the protocol.

Proban will be a good choice for riskand reliability-based application software.