An Optimal Plastic Solution

A Stringer model solution utilizing the plastic behavior of concrete. PolyStringer is a fast and easy way to design reinforced concrete shear walls and diaphragms.

Our clients

Stringer Model

Stringer models have traditionally been solved by hand, however, this is very time consuming and often the solution is far from optimal. PolyStringer allows engineers to find the optimal solution within minutes.
Stringer models are primarily used for reinforced concrete diaphragms and shear walls. However, design of steel structures sometimes applies for the use of stringer models as well.

Concrete Diaphragms

Using a stringer model, reinforced concrete diaphragms can be designed to withstand the shear forces associated with distributing the horizontal loads to the supporting shear walls.

Concrete Shear Walls

For design of stabilizing shear walls with openings, such as in the picture above, the stringer model is ideal for finding the optimal force distribution. 

Optimal Plastic Solution

Statically Indeterminate stringer models have multiple solutions. The optimal solution is the minimization of the required reinforcement. This solution is very true to the actual behavior of reinforced concrete and is easily found using PolyStringer.

Are you ready for an Optimal Solution?

Get your free student license, or get a free trial verion of PolyStringer.


Most frequent questions and answers

To get started with PolyStringer:
  • Download and install PolyStringer
  • The first time  PolyStringer is opened you will be asked to enter your name and e-mail.
  • You are now ready to use the program

A stringer model is an effective method for determining the required reinforcement for a concrete shear wall or diaphragm. This is especially used for designing multi-story precast concrete structures, where the stabilizing system is composed of shear walls and rigid diaphragm. In these structures the concrete diaphragm will often be required to distribute the forces to the shear walls and it is necessary to determine the corresponding reinforcement in the slab.

PolyStringer uses a plastic solution which is an Ultimate limit analysis, the method can therefore in general not be used for serviceability limit state, however it has been shown that using the optimal plastic solution where the required reinforcement is minimized yield reasonable solutions for SLS as well.

A stringer model can also be used for other materials which has a plastic material behavior. To do this correctly in PolyStringer the weight parameters most be adjusted accordingly.

Yes, concrete is a plastic material, and distributes the internal forces in the most advantageous way possible. The optimal plastic solution is therefore very true to the actual behavior of concrete and is recognized as a valid solution in the Danish national annex DS/EN 1992-1-1 DK NA:2013 5.6.1(3).

Plastic solutions for reinforced concrete design is strongly founded in research and are widely used within the construction industry in Denmark.

An Optimal Plastic Solution

The plastic optimization of the stringer and shear forces lead to a solution, where the required reinforcement is minimized. This feature both reduce the overall cost of the concrete structures and is a more accurate description of the true behavior of concrete structures.

Fast and easy to use

PolyStringer has a graphical input area, that allow the user to alter data such as geometry, removal of stringer or shear fields directly. This combined with a speed optimized algorithm for solving the system offers a great user experience.

PDF Export

When you have created and solved your stringer model it is very easy to document your work. Simply click on export, chose which content you want to include and let PolyStringer create a short and elegant PDF document for you. This feature is one of the most liked features among our users.  See example.

PolyStringer licenses are available both as single- and multi-user. Contact us and we will help you find the most suitable option for you.

Poly Stringer

If you are unsure whether PolyStringer is the right software for you,
then click the button below and register for a free trial version. 

en_GBEnglish (UK)