As explained in 2.1.1, it is important to note that the existing moment during the strengthening (Mo) generates an imposed deformation of the tensile steel that cannot be restored unless prestessing the CFRP. This moment can have a significant influence on the necessary CFRP quantity in the SLS in case of a substantial initial moment.
Therefore, the user must input a realistic value for the acting moment (Mo) expected during the strengthening process. This should not include load factors and will be essentially composed of the existing dead loads and a reduced combination of the expected live loads during the installation. This value cannot exceed the strength of the unreinforced member under the Serviceability Limit State (characteristic load). Limiting values are shown beside the input box.