Failure analysis of reinforced concrete was a leading subject for research in the late 80’s and 90’s in Europe, the US and Japan. Mathematical formulations for cracking and crushing of concrete were developed and validated in experimental tests.  DIANA was used as the numerical platform for development and validation of concepts, as well as for the numerical models for cracking of concrete, by a consortium of research organisations.  This formed the basis of analysis capabilities for failure of reinforced concrete structures upon which DIANA was defined.

In the second half of the 90’s, with the support of Dutch Ministry of Public Works, these concepts were further developed into models that could be used in the frame work of a 3-dimensional general purpose program for application on practical structures. In the last decade, the practical application of DIANA, in terms of user-friendliness and performance have been further developed.

For the accurate analysis of damage development, and failure of reinforced concrete structures, the different material characteristics of steel and concrete need to be considered precisely.   DIANA’s reinforced concrete models are based on the exact geometry definition of reinforcements and concrete, the explicit description of material failure of the steel reinforcements, the concrete and the bond-slip connection between both.  This is contrary to many other programs in which models are based on phenomenological behavior in common situations, which cannot be extrapolated to special conditions such as failure of composite structures with specific loading conditions or loading history.

DIANA can perform integral failure analysis of structures, taking into account construction phases and loading history, including heat loadings, stresses from the concrete hardening, soil-structure interaction, dynamic loadings and changing material behaviour with time.

Recently, DIANA has been extended with design checking capabilities for reinforcement grids in plate structures in full 3D models in accordance with modern international design codes.  Also, added is a sequential linear analysis module for easy assessment of Ultimate Limit State, and Serviceability Limit State assessment by a series of linear analysis stiffness in overloaded integration-points, which are reduced in the maximum strain direction in subsequent steps.  In addition, new features have been added at a material level to consider the heterogeneity of concrete, as well as introducing fiber materials in order to simulate fiber reinforced material models.

Thus, in DIANA, design of Full 3D structures, inclusive easy assessment of ULS/SLS and fully integrated failure analysis of reinforced structures can all be done in the same program.

In addition to the reinforced concrete structures 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 would like to ask, please use the webform.

DEDICATED FEATURES FOR REINFORCED CONCRETE

Modelling and analysis features

  • Embedded reinforcements with grids and bars defined independently from finite element mesh
  • Bond-slip reinforcement
  • Pre and post tensioning
  • Reinforced concrete concept applicable in all element types such as solids, plane stress, plane strain, axi-symmetric, shell and plate elements, beam elements and interface elements.
  • Construction-staged analysis for accurate description of loading history
  • Staggered and fully coupled heat-stress analysis for thermal effects on loading of structure
  • Ambient influence on material behaviour
  • Young hardening concrete behavior also with cooling
  • Dedicated post-processing of crack patterns

Material models

  • Discrete cracking with interface elements
  • Multi-directional Fixed cracking with strain decomposition, with possibility to combine with plastic failure for crushing and temperature and creep effects
  • Total-strain crack models with fixed and rotating cracks for tensile and compressive failure, with possibility to combine with temperature and creep effects
  • Creep and shrinkage models according to different international design codes
  • Elasto-plastic models such as Mohr-Coulomb, Drucker-Prager, Rankine
  • Modified Maekawa-Fukuura model for cyclic loading conditions
  • Von-Mises plasticity with hardening for steel reinforcement, and several typical models for cyclic loading
  • User-supplied materials
  • Modified two-surface model for cyclic behaviour of steel
  • Menegotto-Pinto, Monti Nuti, and Dodd Restreppo plasticity models for reinforcements

Modelling and analysis features

  • Full 3D modeling capabilities with solid elements, shells and beams
  • Composed elements which allow to calculating cross-section forces and bending moments in references lines and reference places from compositions of solid and shell elements
  • Automatic coupling of different element types
  • Reference to material definitions of international design codes
  • Mobile loading and influence field analysis
  • Easy definition and handling of load combinations and scanning over results from different load cases
  • Design checks of reinforcement grids

Material models

  • Linear elastic anisotropic and orthotropic models
  • Nonlinear joints
  • Combination with full range of nonlinear material capabilities possible

 

Modelling and analysis features

  • Sequential linear analysis for efficient assessment of limit states
  • Full 3D modeling capabilities with solid elements, shells and beams to be combined.
  • Composed elements which allow to calculate cross-section forces and bending moments in references-lines and reference places from compositions of solid and shell elements
  • Automatic coupling of different element types
  • Reference to material definitions of international design codes
  • Full-loading history and range of loading types can be defined
  • Assessment of onset of plastic failure of reinforcement or concrete cracking and crushing
  • Stiffness adaption analysis

Material models

  • Uniaxial stress-strain relations as input for compression and tension for concrete and reinforcements
  • Fiber reinforced material models
  • Random field material models