With their enormous power, earthquakes can cause substantial disaster to densely populated areas. Earthquakes are sometimes accompanied by water impact loadings resulting from tsunami, collapse of neighboring structures and liquefaction of ground, or fire.
Today, new structures in earthquake sensitive areas are designed to sustain earthquakes without danger of damage or collapse.
But if the condition of the structure has been unknowingly changed, eg. by damage to the structure, deterioration of materials or altered loading, then the effect on earthquake resistance may be significantly altered.
Why use DIANA?
For many non-standard structures, an appropriate earthquake design requires a dynamic finite element analysis. For simple assessment a linear analysis in frequency domain may be sufficient. However, for other applications, the full nonlinear characteristics of possible failure mechanisms, and interaction of the structure,,with ground and environment need to be considered in a nonlinear time stepped analysis.
DIANA offers solutions for both simple linear dynamic analysis, which can be applied for the design of structures, and also full nonlinear dynamic analysis taking into account the loading history of the structure.
In addition to the earthquake engineering specific technical data and specifications below, see also the general functionality information (to the right of this page). Our range of brochures are also available for download. Or, if you have a specific question about DIANA that you would like to ask, please use the webform.
Dedicated Features for Earthquake Engineering
- Linear transient analysis with different time integration schemes
- Direct frequency response analysis
- Modal response analysis
- Spectral response analysis
- Nonlinear transient analysis with different time integration schemes
- Hybrid frequency-time domain analysis
- Pushover load & pushover analysis
All dynamic analysis procedures can be used in combination with fluid-structure interaction effects. At a fluid-structure interface a full coupled acceleration-pressure matrix is calculated for normal displacements on the interface. This interaction matrix accounts for effect of fluid dynamics to the structure in the structural analysis. Frequency dependent effects, e.g. fluid compressibility and boundary damping, can be defined with a range of analysis types.
All structural element types can be used in all available dynamic analysis procedures
- Mass density per unit volume
- Reduced mass density for dead weight correction
- Distributed mass elements with damping properties for defining non-reflection boundaries
- Consistent and lumped concentrated translational masses and rotational inertia
- Viscous or Rayleigh damping
- Structural or hysteretic damping
- Continuous damping via discrete spring/dashpot elements
- Base excitations, single and multi-directional
- Prescribed nodal accelerations (2011) and displacements
- Time-load diagrams, e.g. accelerograms
- Frequency-load diagrams, e.g. spectra
- Specified initial displacement and/or velocity fields
- Initial stresses
- Possibility to add stress-stiffness to linear elastic stiffness matrix in frequency analysis
- For direct Frequency Response output of complex results and/or amplitude-phase results
- Lanczos Eigensolver withvarious decomposition techniques, shifting option, and automatic ordering
- Spectral Response with ABS, SRSS, and CQC output
- Euler backward, Newmark, Wilson-theta, Hilber-Hughes-Taylor, and Runge-Kutta time-integration
- Total-strain cracking models
- Modified Maekawa-Fukuura concrete model ( Multi-Axial Damage and Cracked Concrete models)
- Monti-Nuti-steel model
- Modified 2-surface steel model
- Hardin-Drnevich and Ramberg-Osgood simple soil models
- UBC, Bowl, Nishi and Towhata-Iai liquefaction models
- Engineering liquefaction analysis