Powered by the advanced and flexible graphical interface of new spSection Module for creating and modifying irregular sections, spColumn v5.50 is widely used for design and investigation of columns, shear walls, bridge piers as well as typical framing elements in buildings and other structures. Equipped with latest American (ACI 318-14) and Canadian (CSA A23.3-14) Concrete codes, spColumn is developed to design and investigate any reinforced concrete sections subject to combined axial and flexural loads. Formerly pcaColumn, PCACOL, and IrrCOL, spColumn investigates sections that are impossible to find on design charts or to do by hand. The section can be rectangular, round or irregular, with any reinforcement layout or pattern. The program offers investigation of irregularly shaped, reinforced concrete column sections that may contain openings or boundary elements. Top selling worldwide, spColumn provides a full featured 3D visualization of the nominal and factored failure surface. Import/export of DXF files, nominal interaction diagrams, and display of capacities at your load point are just a few of the rich program features.
The analysis of the reinforced concrete section performed by spColumn conforms to the provisions of the Strength Design Method (CSA A23.3) and Unified Design Provisions (ACI 318). All conditions of strength satisfy the applicable conditions of equilibrium and strain compatibility.
For the ACI codes, the nominal (unreduced) capacity of the section is first computed. Then, the nominal capacity is reduced to the design capacity using the strength reduction factor, Φ.
spColumn computes the interaction diagram (uniaxial runs) or the three-dimensional failure surface (biaxial runs) of the input section. The values of maximum compressive axial load capacity and maximum tensile load capacity are computed. These two values set the range within which the moment capacities are computed for a predetermined number of axial load values.
Based on the specified minimum, maximum and increment specified for the section and the reinforcing bars, the program selects the smallest section with the least amount of reinforcement for which the load-moment capacity exceeds the applied loads. Depending on the design criteria the user selects, the least amount of reinforcement the program searches for means either the smallest number of bars or the smallest steel area.
The program starts the design by trying the smallest section (minimum dimensions) and the least amount of reinforcing bars. The program verifies that the ratio of provided reinforcement is always within the specified minimum and maximum ratios. Furthermore, unless otherwise specified by the user, the bar spacing is always kept greater than or equal to the larger of 1.5 times the bar diameter or 1.5 in. [40 mm] for ACI and 1.4 times the bar diameter or 1.2 in [30 mm] for CSA.
Slenderness effects producing magnified moments through moment magnification procedure (ACI 318-14, 6.6.4, CSA A23.3-14, 10.15, 10.16) can be considered both for design and investigation of sections in lieu of complicated and time consuming 3D analytical models.
Since ACI 318-08 moments in compression members in sway frames are magnified both at ends (ACI 318-14, 220.127.116.11) and along the length (ACI 318-14, 18.104.22.168). In ACI 318-02/05, and CSA A23.3-94/04/14, magnification along length applied only if lu/r > [35/sqrt(Pu/(f’c*Ag))]. Moments in compression members in nonsway frames are magnified along the length only. See flowchart below.
* Excerpt from " Observations in Shear Wall Strength in Tall Buildings" presented by StructurePoint at ACI Spring 2012 Convention in Dallas, Texas
The above mentioned procedure is now shown in ACI 318-14 with a flowchart (ACI 318-14, Fig. R6.2.6).
Additional 20% discount available for multi-product bundle purchase spMats, spBeam, spColumn, spSlab, spWall, spFrame (formerly pcaMats, pcaBeam, pcaColumn, pcaSlab, pcaWall, pcaFrame). Email us at info@StructurePoint.org for more information on pricing and licensing.