spSlab versions

v3.6 [Apr 13, 2013]
Resolved Issues:
1. In investigation mode where required shear capacity provided by stirrups, Vs, exceeds 4*phi*Sqrt(f’c)*bw*d and user-provided stirrup spacing exceeds the halved ACI code maximum, the shear capacity -- instead of previously used 4*phi*Sqrt(f’c)*bw*d -- is now reduced to 0.5*phi*Vc resulting in lower beam shear capacity
2. Shear and torsional capacity in segments between support face and critical section for shear at span ends is now investigated explicitly rather than assumed to be the same as at the critical section for shear. In cases where shear reinforcement is reduced or discontinued between support face and critical section for shear, this may lead to insufficient shear and torsional capacity reported by program in the vicinity of supports.
3. For lightweight concrete beams, the lambda factor is now included in Vc to calculate the shear force threshold that triggers the halved ACI code maximum stirrup spacing potentially resulting in smaller stirrup spacing requirements
4. In investigation mode, to ensure that flagging of exceeded shear capacity in text results report matches the graphical results, text output now includes more segments where shear capacity is checked against the shear force
5. Improved program ability to recognize and flag in results report special conditions, such as stirrup area below minimum condition and inadequate stirrup spacing condition, encountered in shear design and investigation
6. For a single span model, the effective moment of inertia was modified to include only the effect of the midspan section instead of previously used midspan and right end sections. In single and multi-span beams, fixed ends are now treated as continuous end conditions. Depending on beam geometry and loading, the changes introduced in calculating Ie,avg can potentially result in a lower Ie,avg and higher deflections.