The design of the crack width limitation can be carried out in different ways according to Section 7.3 of EN 1992‑1‑1. Allowable crack widths are considered to be given and designed according to Eurocode 2, if:
1. The available crack width wk is smaller than the allowed limit value when calculating the crack width wk directly according to 7.3.4, or
2. According to 7.3.3, without direct calculation of the crack width
- The limit diameter lim ds according to Table 7.2 is larger than the available rebar diameter of the tension reinforcement, or
- The maximum rebar spacing lim sl according to Table 7.3 is larger than the available rebar spacing of the tension reinforcement.
Therefore, it is sufficient for the crack width analysis when one of the design methods mentioned above is fulfilled. The "Find the most economical reinforcement for crack width design" option checks which of the selected methods for crack width limitation can be covered with the smallest possible reinforcement area.
Programs add reinforcement bars one after the other to the provided reinforcement until this design is fulfilled. Result Tables 4.2 show the results for lim ds, lim sl and wk, even if only one limit value governs for the crack width design.
