History of TNO DIANA BV

For those interested, this section gives a brief summary of the history of the DIANA code.

Birth

In succession to the development of a special purpose finite element program for linear analysis of orthogonal structures (named COLOS), in the early 1970s - TNO Building and Construction Research originated the development of the DIANA finite element code in 1972.  Initially, the idea was to develop an in-house code for consultancy work in the field of concrete mechanics and civil engineering. As the code was based on the displacement method, it was called DIANA which is an acronym for DIsplacement ANAlyzer.  At that time, the computer facilities consisted of a remote terminal for submission of punched card jobs to a CDC-6600 main frame computer.  The primal version of DIANA was running in 1974.  The source code comprised about ten thousand punched cards, stored in five strong steel boxes.

First analyses

The young DIANA was a tool for the analysis of real structures and TNO was lucky to obtain contracts for the analysis of some complex off-shore structures in 1975.  It turned out that software development and structural analysis required a lot of computer jobs and that the bottleneck for progress was the remote computer service.  To perform the modeling of the structure and interpretation of the analysis results, the need for mesh generation, and plotting facilities became obvious.  Furthermore, particularly for the analysis of large reinforced concrete structures, it would be desirable to include nonlinear phenomena such as cracking of concrete and plastic deformation of steel.  To cope with all these problems and requirements, in-house computing facilities were urgently needed.

In-house use

In 1975 TNO-IBBC purchased its first mini-computer, a Harris/4 with about 48Kb of core-memory and 2 x 10 Mb of disk space.  It was chosen because of its 24-bit architecture, which yielded more accurate analysis results than the popular 16-bit PDP-11/45 of Digital Equipment Corporation.  However, because of the lack of memory, many programming "tricks" had to be used to get a feasible implementation.  One of these tricks was the development of the file and memory management system FILOS which, in modified form, still serves as a special database management system for DIANA.  To facilitate the creation and checking of the finite element model, two new modules were developed: MESH for automatic mesh generation and GRAPHI to display the model and its analysis results.  Both modules came available in 1977, and were used to analyze parts of the `Oosterschelde Deltawerken' in Zeeland.  At that time, DIANA's reinforcement modeling option was a unique feature, not available in competitive finite element codes.

Developing advanced analysis methods

Having the Harris computer in-house, the turn-around time of analysis and development jobs decreased dramatically.  Moreover, new sponsors became interested in TNO's R&D activities: the Dutch MATS and CUR research funding organizations.  The CUR organized a large Concrete Mechanics project which lasted until 1990 and was carried out in cooperation with the Technical Universities of Delft and Eindhoven and with the Dutch Ministry of Transport and Public Works.

Both the in-house computing facility and the research funding enabled the development and implementation of more advanced analysis methods, this resulted in the first working versions for nonlinear and dynamic analysis around 1978.  DIANA's first brochure tells all about the facilities at that time: for instance 3-dimensional analysis of concrete structures, including crack analysis and plastic deformation of embedded steel reinforcement.

External use

In 1979 the Harris computer was replaced by a more powerful and accurate machine: a 32-bit VAX-11/780 of Digital Equipment Corporation, running the VAX/VMS operating system.  Also at that time, the first version of the DIANA User's Manual was completed, still in Dutch and printed on a line printer.  DIANA had now grown to about 200.000 statements and gradually, the attractiveness of the code was also recognized by engineering offices and researchers outside TNO.  For this reason, the first professional executable product version of DIANA was prepared.  The DIANA-1 release was delivered to the Dutch Ministry of Transport and Public Works in the Hague in 1980, to run on a UNIVAC-1108 main frame computer.

Entering the market

A VAX-11/780 at that time cost somewhat more than half a million Dutch guilders (US$200.000), which was more than small engineering consultant companies could afford.  TNO did realize that, to enter the market with application software for structural analysis, it would be essential to have it running on low-cost computers.  However the personal computer in those days was not sufficiently powerful for an application like Finite Element Analysis.

Fortunately, there was an R&D project going on at TNO to develop a low cost, but powerful micro computer for Computer Aided Design applications: the GEMINIX, based on the Motorola MC-68000 processor and probably the world's first micro computer running the UNIX operating system.  DIANA was successfully ported to the GEMINIX and in 1983 this combination was installed at three customer sites: two engineering consultant companies and the Public Works department of Rotterdam.

A growing user community

As their number increased significantly, the external users wished to organize themselves.  This led to the establishment of the DIANA Users Association in 1984, a platform for exchange of users' experience, which also indicates priorities for new developments toward TNO.  This led to the DIANA-2.0 release in 1988, with new modules for potential flow analysis, and for connection to external pre and post processors.  The 2.0 release came with a user's manual and a user's course and text book, now all in English which allowed DIANA to go international.  The first customer outside The Netherlands was the University of Darmstadt in Germany.

In the late 1980s, the research community discovered DIANA's potential as a software development environment in addition to its service for end-use.  TNO's major partners asked for access to the source code and the associated programmer's toolkit to establish their own developments in DIANA.  This marked the birth of the DIANA Foundation on May 9, 1989, a joint initiative of universities, research institutes and industrial partners.  The role of TNO was, and is, to transfer these developments to the product version of DIANA, including quality assurance, documentation and maintenance, to achieve continuity of the developments.  Since January 1991 the Foundation has been recognized and approved by the Netherlands Organization for Scientific Research (NWO) as Expertise Center for Computational Mechanics.

Marketing and support for new releases

In order to provide high quality maintenance and development of DIANA, TNO appointed DIANA Analysis BV in 1990 to manage sales, marketing, promotion, and first-line support of DIANA.  The 3.2 release was the first release to be distributed and supported by DIANA Analysis BV.  It came with new modules for fracture mechanics, dynamic response, and stability analysis.  The element library was extended with flat shell and interface elements, and with elements for groundwater flow analysis. DIANA-4.1 was released in 1991.  Significant extensions in this release were an iterative solver, phased analysis, indirect displacement control in nonlinear analysis, and a new family of orthotropic membrane elements.

The members of the DIANA Foundation asked for more information about the DIANA programming environment.  Therefore TNO developed a programmers course, this was given for the first time in 1992.  The programming environment was supported primarily on powerful workstations under UNIX.  However, the power of personal computers had increased to such an extend that the users community asked for a port to the MS-DOS operating system.  This was established in 1993 with the DIANA-5.1 release. Important additions to the analysis features in this release were a substructuring technique in the solution procedure, stability analysis with imperfections, nonlinear analysis control improved with arc-length and automatic load control, and new modules for parameter estimation, and pipeline analysis.  The element library was extended with higher order elements for various families and with layered elements.

Getting mature

In 1994, the DIANA user community had grown to such an extent that it became about time for the "First international DIANA conference on computational mechanics", jointly organized by DIANA Analysis BV, the DIANA Foundation, the DIANA Users Association, and TNO.  The next release was DIANA-6.1 in 1996, with improved meshing facilities, an iterative solution method optimized for vector and parallel computers, the analysis of wind and water wave load, a line search algorithm for nonlinear analysis, nonlinear dynamics, postbuckling, and contact analysis.  New material models for clay and concrete were added, as well as models for viscoplasticity and viscoelasticity.  The new user-supplied subroutine option supported a general material model of particular interest for R&D sites.

With respect to postprocessing, the 6.1 release brought facilities to determine and plot influence lines and to make contour plots. The external pre and post processor FEMGV was coupled to DIANA to provide for an interactive graphics interface, including general meshing and color plots of analysis results.

Twenty five years and onward

On the occasion of DIANA's 25th birthday, the "Second International DIANA Conference on Computational Mechanics'' was held (in June 1997).  As DIANA was, and still is, characterized by two key-words: research and end-use, the conference brought together researchers and end-users engaged in finite element modeling, plus new developments in computational mechanics.  The titles of the various sessions indicate DIANA's wide variety of applications: "Concrete mechanics and concrete structures", "Geomechanics and soil-structure interaction", "Steel and composite structures", "Computational mechanics of materials", and "Finite element technology and software development".

In 1998 DIANA-7.1 was released.  An important improvement was the enhanced DIANA environment for the FEMGV-5.2 pre and post processors.  Another new feature in the user-interface was the online version of the users manual, to be used via a web-browser.  The 7.1 release offered new material models for concrete cracking and crushing, an option to simulate corrosion of reinforcement steel, a module for mobile load analysis, and extended options for geotechnical analysis.  As of the 7.1 release, DIANA also supported the MS-Windows platform for PC's.

DIANA-7.2 was released as an upgrade to 7.1 in 1999, now combined with FEMGV-6.1 with many enhancements for interactive graphics pre and post processing and a fully integrated on-line user's manual.  Another important enhancement was the availability of new constitutive models, particularly suited to analyze the liquefaction of saturated soil due to earthquakes.  Together with DIANA-7.2 TNO introduced a new product called `Micro-DIANA'.  For the benefit of a reduced license fee, Micro-DIANA has all the analysis capabilities of the mother program but allows a limited number of nodes in the finite element model.

The new millennium

In 2000 the development of two major product lines was initiated:

1. The complete integration of DIANA and FEMGV, resulting in the general purpose graphical interactive environment iDIANA in version 8.
2. Special purpose versions of DIANA with dedicated graphical user interfaces for specific applications.

Shell International Exploration and Production BV commissioned TNO to develop special versions of DIANA for their private usage.  The choice for the two product lines required a restructuring of the code such that components with clear tasks are identified which can easily be combined in new applications.  In parallel Femsys Ltd was ordered to extend FEMGV with specific functions for DIANA, such as reinforcement preprocessing, hierarchical property forms, menu configuration on selected model types, visualization of cracks etc.  The year 2000 was, world-wide, a very successful year for new sales as the number of licenses increased with 40%.

In 2001, the first results of the research project '4D-Computing' came available in the development version in the form of two new solvers: Sparse Cholesky and ILU-preconditioning. This project aimed on speeding-up DIANA and was supported by the D.O.V.  In the same year DIANA-2D was introduced, a special version for the analysis of two-dimensional models.

The first major release of the new millennium was introduced in 2002 as DIANA-8.1.  It came with a fully integrated pre and post processing environment iDIANA, derived from FEMGV-6, and a graphical interactive control of analysis commands.  New material models came available particularly suited for analysis of soil and concrete like Delft Soft Soil, Hoek-Brown, and Rankine Hill anisotropic.  Also added were models for young hardening concrete.  Among the new analysis capabilities were a module for spectral response analysis and the new solvers.

In October 2002 the "Third DIANA World Conference'' took place in Tokyo.  By this time, Japan had become the most important export market for DIANA.  The emphasis of the conference was on application of advanced computational models in civil engineering applications.

A new organisation for DIANA

In 2002, TNO prepared a new organisation around DIANA: a company named TNO DIANA BV was founded and in the beginning of 2003 all technical activities were transformed from TNO Building and Construction research to the new company.  Also the marketing and sales activities, until then being done by DIANA Analysis BV, were transferred to TNO DIANA BV.  At the same time TNO DIANA BV became owner of Femsys Ltd.  Thus a new organization had been created in which commercial and technical activities were integrated with the purpose to direct services in an optimal way to DIANA users worldwide.

In May 2003, the Second edition of release 8.1 was made available.  In this version the remaining applications, such as Fracture Mechanics Analysis and Beam Cross-section Analysis, were included in the graphical user interface.  Also some new line interface elements for shells were introduced.

At the end of 2004 DIANA-9 was introduced.  This version offered a completely new interactive Graphical User Interface.  Various analysis functions were also added.  For instance new automatic nonlinear solution procedures, complete plane strain elements, and improved options for geotechnical analysis.

In 2005, a strategic decision has been made to expand the business from the high-end niche market for advanced nonlinear analysis software that was traditionally served with the DIANA program only, to the markets for design and analysis software.  We realized that in the daily design practice ease of use is the key-word and that analysis tools must be tailored to terminology and working procedure of design engineers.  At the same time we have chosen to focus the inhouse software development activities on the DIANA finite element solver functionality and to look for strategic partners for the development of pre and post processing software components both for the high end general purpose users as well as new application oriented design software products.

Strategic Alliance with MidasIT

In December 2005, TNO DIANA BV entered a strategic alliance with MidasIT, based in Seoul in South Korea.  The alliance is for joining forces in product development and distribution of each-other products.  Midas will focus on the distribution of products in Asia and TNO DIANA on the distribution of products in Europe and the United States.  The advanced nonlinear analysis functionality will be developed at TNO DIANA in Delft, whereas MidasIT will take the lead in the development of the design applications and the pre/post processing programs.

The DIANA version 9.2 that was the first version of DIANA being integrated with the Midas FX+ pre and post processor was introduced at the end of 2006.  This new combination impressed the market for its powerful combination of robust nonlinear 3-dimensional analysis functions and easy to use intuitive pre-post-processing programs.

Earlier in 2006, the Femsys office in Leicester was transferred into a TNO DIANA UK office in Woking, close to London, focusing on the distribution of the Midas products midasCivil for bridge design and analysis and midasGen for design of buildings and more general structures.

In 2007, the first international bridge seminar was organized in London, on the topic of Integral bridges, followed by the 2008 seminar on Cable-stayed bridges and the 2009 seminar about Construction stages in Bridge engineering.

Parallel processing of solvers and full 64-bits architecture was offered in DIANA version 9.3 in 2008 and also the FEMGV program was transferred to 64-bits architecture in this year.  This development opened the route to faster analysis of larger models and this development got an enormous boost in the following year.

Since 2005, in a close co-operation with the DIANA User Association the international User meeting has been organized at varying locations in Europe. During these events users exchange experiences in using the software and wishes for new developments are discussed between users and developers.

In 2008, MidasIT and TNO DIANA BV decided to strength the co-operation and integrating DIANA as solver in the fully integrated products midasGTS for 3-dimensional geotechnical and tunneling analysis.  This product offers CAD-type model definition with fully automatic meshers and non-linear solvers in an integrated program.  This fully integrated product can efficiently be used by design engineers, not necessary being experts in finite element analysis.

A major new DIANA version (9.4) was launched in 2009 and the integrated GTS-DIANA  program was introduced in the Spring of 2010.  This new DIANA version offered more parallel processing functionality as well as a wide range of new finite element functions such as bond-slip options for embedded reinforcements, which can also be used to model pile foundations, additional soil/rock models and more.

Early in 2010, DIANA 9.4.2 became available offering new element types, eg. curved shell elements will drilling rotations and linear fluid-structure interface elements, in the D-min soil material model, and additional analysis functionality.

In the Autumn of 2010, DIANA 9.4.3 was released.  In this version the possibility to use precompiled library files for user-supplied subroutines, plus two new analysis types for sequential linear analysis and reinforcement grid design checking, were introduced.

As of January 2011, TNO DIANA BV took the decision to no longer sell or market MIDAS products, instead focusing it's sales and marketing activities on the flagship product DIANA.  TNO DIANA BV and MIDAS IT continue their existing technical collaboration and technology transfer between their respective products.   Throughout 2011, TNO DIANA BV continue to support its existing MIDAS customers providing both technical supports and upgrades to software.