The Strain Analysis tab within the View/Update page reports the rectangular compression block parameters at all locations along the span. The neutral axis depth c , the Whitney block depth a , the strain in the extreme tension steel at concrete rupture ε _t , and the phi factor for flexure, are reported for the selected location along the span. In addition, the section is reported as tension-controlled, in transition, or compression-controlled according to the limits specified by ACI 318 (see Section 5.8.1). This tab is available only for the ACI 318-05 and ACI 318-08 design codes.