15.4.13
If there is reinforcement corrosion or insufficient clamping length in the existing structure, the reinforcement corrosion multiplier and the insufficient clamping length yield stress factor values are defined while performing the performance analysis. When the reinforcement corrosion factor and insufficient clamping length yield stress factor are defined, the reinforcement area is automatically reduced and the element capacities are calculated accordingly.
Overlap lengths and interlock hooks are automatically taken into account when defining the reinforcement.
Insufficient Clamp Length Yield Stress Multiplier value , which indicates the rate of deficiency in clamping or overlapping length , is entered by the user.
In the case of insufficient clamping or overlap length of reinforcement in reinforced concrete elements, the relevant reinforcement moment curvature relationship is not taken into account in the calculation of the section capacity moment.
In the picture below, there is a reinforcement layout shown in a sample beam. Here, the reinforcements that do not provide overlap length in i end, j end and opening regions are not taken into account in moment curvature.
In the picture below, the fiber models to be used in the i end, span and moment curvature analysis at the j end for the beam with reinforcement placement are given.
If there is a deficiency in the clamping or overlapping length in the reinforced concrete elements of the existing structure, the yield stress of the reinforcement can be reduced with the insufficient clamping length yield stress multiplier . The value to be written in this section must be 1 or less.
For example, let's consider the yield stress fsy =420 MPa of a reinforcement calculated for the current material strength and comprehensive knowledge level . If the insufficient clamping length yield stress multiplier is calculated as 0.8, 0.8 is written in this section and the reinforcement yield stress of the element in question is now calculated as f sy = 420*0.8 = 336 MPa.
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