The limiting stresses are calculated according to IRC 18-2000 Clause 7 and IRC:SP71-2006 Clause 3.2.2.

Precast/Prestressed Girder checks and marks with asterisks (*) the stresses exceeding the limiting stresses under Service I and Service II. For simple spans, only the stresses under the positive moment envelope are checked, and for multi-spans, stresses under positive and negative moment envelopes are checked. Note that Precast/Prestressed Girder will also mark the stresses exceeding the limiting compressive or tension stresses at release.