Impact and Structural Modelling

For many years, NNL has been leading the way in impact and structural modelling. An area of expertise vital to the smooth and safe running of nuclear plants, it's also key to the future of nuclear new build programmes. Focusing on advancing new or existing plants and their equipment, our industry-leading professionals bring a range of outstanding engineering analysis to the team.

NNL has provided engineering and modelling simulation for more than 25 years. Our professional service focuses on delivery, safety and quality. We demonstrate the acceptability of nuclear plant and equipment through engineering analysis. Our service ranges from design assessment and optimisation of new plant and equipment to the assessment of existing plant and equipment over anticipated operational lifetimes.

There are four key service areas we provide, covering structural, seismic, impact and dynamic assessments:


We're able to assess a range of stresses and behaviours as well as remnant plant life. We also assess mechanical equipment such as pressure vessels and pipework. On top of this, we can provide a service to assess against code allowables such as ASME III and BS7910.


Our seismic assessment service provides a range of options for customers, including:

  • Design seismic calculations
  • Response spectra analysis
  • UK design basis earthquake assessment
  • Audit and issue of seismic certificates
  • Best practice design and assessment guides


Our impact service covers a range of areas including transport flask and waste packages, accident scenarios and non-metallic materials:

  • Various drop tests
  • Concept design development
  • Release fraction predictions
  • Penetration and perforation
  • Aircraft impacts
  • Concrete, Wood, Grout, Cork, Foam and Rubber


Our dynamic service supports customers across several key areas 

  • Dynamic loads from road/rail/sea transport
  • Vibration effects
  • Blast and explosion loading
  • Fluid-structure interaction
  • Simulating dynamic plant operations