Last modified by Fredrik Lagerström on 2020/05/29 14:43

The speed of a PRE-Stress calculation depends on the complexity of the calculation being performed. By default, PRE-Stress is set to provide a good balance between accuracy and speed, but these settings can be altered if desired.

PRE Perf 001.png

To configure the amount and position of calculation sections, select the beam element in the project tree handler, then select the Calculation sections tab. This tab displays the calculation sections that the program uses for the calculation.

PRE-Stress performs its calculations by using the Finite Element Method in which the beam is subdivided. Upon calculation, an element is split into smaller calculation segments, and the calculation is performed on each segment in succession. Reinforcements and loads are also split. Should one of these segments be cracked, the program alters the stiffness of the segment before repeating the calculation by iterations, ending when a stable stiffness distribution has been reached. 

The list of sections are default values given by the measurements of the beam, but you can easily remove sections (trading accuracy for calculation speed) as well as add them (improving accuracy at the risk of slower calculation). Numbers given in blue denote sections that can't be removed or altered.

Note that while the calculation sections may appear similar to the sections shown during presentation of results, they are not identical. For one, an increased number of calculation sections will not show a corresponding increase in number of sections in the result tables.

Not all tradeoffs are gainful. For instance, example four. mentions the option to increase the number of sides of the polygon representing the shape of the hole. By raising the value, the polygon progressively approaches a circular shape, but each successive increase will provide a smaller increase in precision while linearly increasing calculation time.