ACI-318 / ACI-350 Beam Column Design

This calculation evaluates concrete members carrying both flexure and axial load using thrust-moment, or P-M, interaction diagrams generated per ACI 318 and ACI 350. Standard axial/flexural provisions, Ch 10, are considered.  ACI 350 durability factor is used to factor down the flexural and axial capacities instead of factoring up the factored loads. The end result is an "inner curve" that governs for ACI 350 capacity in the tension-controlled and transition zones.

UPDATE 2.1: Bug Fixes and point-by-point capacity checker added. Individual key points, checked using XLC, will be added in forthcoming version 2.2.

UPDATE 2.0: Significantly expanded range of acceptable column designs and enhanced usability - frequent PM Interaction diagram users will feel right at home. Individual key points, checked using XLC, will be added in forthcoming version 2.1.

UPDATE 1.1: Fixed plotting issue in cases with different clear covers between top and bottom face bars.

LIMITATIONS: 

1) Only rectangular sections are supported

2) Ties are provided for confinement (not spirals)

Purpose:

This calculation evaluates concrete members carrying both flexure and axial load using thrust-moment,or P-M, interaction diagrams generated per ACI 318 and ACI 350. Standard axial/flexural provisions, Ch 10, are considered.  ACI 350 durability factor is used to factor down the flexural and axial capacities instead

of factoring up the factored loads. The end result is an "inner curve" that governs for ACI 350 capacity in the tension-controlled and transition zones.

Assumptions/Limitations:

- Ties are provided for confinement (not spirals)

Validation:

-XLC formulae and peer review provide verification of intended functionality.

-Cross-check against software solution (SP Column)

References:

-ACI 318-11

-ACI 350-06

Calculation Reference

ACI 318

ACI 350

Reinforced Concrete Design