Interactive Software
                                 for Structural Design

Why ISSD ?
User's guide


Why ISSD ?

The majority of the commercial software, distributed by the few suppliers on the European market, can perform very complex calculations ranging from the dynamic analysis, the calculation of instabilities to the time responses.

However, control of this software requires regular use, several dozens of hours of familiarization and reading of tiresome instructions.

One observation becomes crystal clear: the software which will be used in the decades to come should be able to carry out complex calculations, but should especially be simple and very intuitive to use.

It is rather disconcerting that, from one software to another, the number of operations (e. g. click, double click, confirmation or introduction of certain data, etc) necessary in order to obtain a result is sensibly different. This difference proves that the software developers devote more resources to improve the calculation capacities of their software than to optimize their ergonomics.

The majority of the engineers or architects however frequently need a quick answer (in terms of forces, stresses or displacements) for relatively simple problems, in sketch stage, conceptual phase or budget evaluations: Especially in these circumstances, they need a simple, user-friendly and fast 2D software and not the particularly complete set of calculations from traditional software.

These observations led to the idea of conceiving software based primarily on simplicity, ergonomics and the speed of the provided results, while allowing the analysis of complex 2D structures.

Considered as a very powerful didactic work tool for the calculation of structures and material strength, the “career” of ISSD started at European universities or colleges. It was then supplemented to fulfill the requirements of the engineering and design offices (profile catalogue, second order calculation, P-deltas, catalogue of structures, beams on elastic ground, etc) while preserving its great ease of use.

Hence, ISSD software is characterized at the same time by an ease of use, pushed to the extreme, and by an advanced capacity of calculation: it could be seen as the “pocket calculator” of the structural engineer of stability, the architect, the engineer on site, the controller or quantity surveyor.


- Very user-friendly, intuitive and fast drawing of the structure
- Calculation of all 2D frame types
- Data base of commercial steel sections
- Overview of the diagrams of several structures on the same screen
- A calculation note can be easily incorporated in WinWord
- Simultaneous overview of the diagrams of stresses and displacements
- Animation of the deformed structure
- Composed welded I and T-profiles
- Data base of arcs and trusses
- Beams on elastic ground
- Second order calculation, calculation of P-delta effects
- Calculation of the critical load for the entire structure or a part of it
- And many more possibilities…...


Ecole Polytechnique Fédérale de Lausanne (EPFL), ISA St Luc Bruxelles, TU Heindhoven, Ecole Polytechnique de Bristol, Université d'Amiens-Picardie, Ecole d'ingénieurs de Genève, Ecole d'architecture du Languedoc-Roussillon, Université catholique de Louvain (UCL), Ecole centrale des arts et métiers de Bruxelles (ECAM), Vrije Universiteit Brussel (VUB), bureau d'études ERCC, bureau d'études Setesco, Samyn&Partners, Faculté universitaire agronomique de Gembloux (FSAGX),Société Composite Support & Solutions Inc (USA), Ecole d'architecture de la Cambre à Bruxelles, Iles de paix (ONG), Entreprise Galère, EIV sprl, Studiebureau Vanlommel.


Contact: www.uclouvain/gce

Price per licence: 990 euros.

Price for installation in computer room with use by students: 1500 euros (independently of the number of stations).

Price for installation on several computers of the same organization or company: on request.

Price for individual student (with copy of the student card): 95 euros.

Above prices do not include 21% VAT


Truss calculation : one can see the value of the axial forces at the same time as the deformed structure. The compressive forces are shown in red, the tension forces in blue and zero forces in green. The line thickness is proportional to the value of these forces.


Drawing of the structure : the nodes of the structure are placed manually on the grid using the mouse. The loads and the supports are deposited with the mouse by a simple “drag-drop method”. The geometry can quickly be modified at any moment.


Choice of the sections and the profiles : all material types can be chosen, either for all the bars or for every bar separately. It is possible to choose standard steel profiles from a database or even to define welded, composed profiles. The geometry of the chosen section is represented automatically.


Beam calculations : ISSD is an excellent tool to compare different structures drawn on the same screen. This facility allows easy analysis of the influence of the position of a support or a load on the value of the forces, the stresses and the displacements.


Characteristics of the bars : a simple right click on a bars enables to open a window that displays the characteristics: material, as well as section type, volume, internal forces,…


Deformed structure and characteristic of the nodes : an animation of the deformations is possible, which is useful within a didactic framework. Furthermore, a right click on a node enables obtaining its characteristics: reaction forces of supports, displacements,…


Determination of the buckling shapes : the image below shows the first buckling mode of a parabolic arc.


Application example/calculation of piles : ISSD makes it possible to quickly determine the ideal position of piles under a massive foundation unit.