ASDIP STEEL is structural engineering software utilized by engineers for design of steel base plate, steel and composite beam, steel columns, and other structural steel members. ASDIP STEEL is based upon the latest AISC specifications (AISC 360). ASDIP STEEL substantially simplifies time-consuming calculations for structural engineering design.
A steel column is a structural member which mostly works in compression and bending and only very short columns can be axially loaded to their yield stress. Often buckling, or sudden bending as a result of instability, occurs prior to developing the full material strength.
This module performs the design of a steel column subjected to axial load and bending moments about its two principal axes. The program is based on the AISC ASD/LRFD methodology and checks the axial, bending, and combined stresses according to the AISC 360-10 Specifications (14th Ed. Manual). Either service or factored loads may be specified.
Two types of procedures may be followed in order to calculate the required strength and the design requirements, depending on the source of the loads entered as input data:
a) Second-Order Analysis, which considers the P-Delta and P-delta effects. No further load magnification is required.
b) Amplified First-Order Analysis. In this case the program will calculate the amplified moments based on the information provided, to account for the slenderness effects.
The input data required by the program includes the material properties and member geometry, as well as applied loads. In addition, the effective length K-factors in both X and Y directions are required. Use the buit-in properties database if necessary.
As an example, consider a 30′-0″ W10x54 steel column subjected to a factored axial compression of 100 k and bending moments of 60 and 20 k-ft around the strong and weak axis respectively. Effective length factors are Kx = 1.0 and Ky = 0.7. Loads are the result of a second-order analysis.
The design process is simple with ASDIP Steel. First, enter your input data using the rich set of controls. Then use the Design Manager to find all the steel sections that meet the design criteria. Sort the table if you wish, either by weight or by design ratio. Finally, when you select one of these winner sections, the corresponding properties are transferred automatically to your calculations.
In this example, the proposed column size is adequate since the design ratios for compression, flexure and combined forces are 0.29, 0.29 and 0.69 respectively. Further optimization is possible since the controlling ratio is 0.69 and there is room to select a lighter section.
Beams are structural members that mostly work in bending and shear as a result of transverse loading. Other terms such as girders, joists, purlins, stringers, girts and lintels are often used. The compression flange, which is attached to the web in the plane of the beam, may or may not be laterally braced, thus the buckling concepts of compression members apply to beams as well.
Composite action is developed when two load-carrying structural elements, such as a concrete floor slab and its supporting steel beams, are integrally connected and deflect as a single unit. The stiffness of a composite floor is substantially greater than that of a concrete floor and its supporting beams acting independently. In addition, a 20 to 30% savings in steel weight is often possible by taking full advantage of a composite system. Since the concrete slab exists anyway and the shear connectors are inexpensive and easy to install, it is structurally advisable to use composite construction whenever possible.
This module performs the design of a simply supported, either interior or border, either steel or composite beam subjected to distributed and concentrated loads. Two cantilevers may be modeled. The program computes the maximum bending moment, shear force, and vertical deflection induced by the applied loads, and compares them against the beam strength. The program computes the number and spacing of the shear studs or connectors required to develop either partial or full composite action, as well as the required camber.
The software is based on the AISC ASD/LRFD methodology and calculates the shear and flexure strengths according to the AISC 360-10 Specifications (14th Ed. Manual). Either service or factored loads may be specified. For composite beams, a simple click opens a new tab to enter the corresponding information.
The required input data consists of steel yield strength, member length, and lateral bracing. In addition, for composite beams it is required the slab thickness and beam spacing. as well as metal deck and shear studs information. You may specify a partial distributed load and up to six concentrated loads.
As an example, consider a 30′-0″ simply supported W18x35 interior composite beam subjected to a factored concentrated load of 7 kip, and 3 kip during construction, at midspan. The beam is laterally braced at 10 ft from the left support. Concrete slab is 5″ thick overall on 2″ metal deck, which is oriented transversely to the beam. Beam spacing is 5′-0″. Use 3/4″ shear studs.
The design process is simple with ASDIP Steel. First, enter your input data using the rich set of controls. Second, specify the design criteria, such as the allowable deflection and camber, shear connectors, etc. Then use the Design Manager to find all the steel sections that meet this design criteria. Sort the table if you wish, either by weight or by design ratio. Finally, when you select one of these winner sections, the corresponding properties are transferred automatically to your calculations. That’s it !!
For a quick check of the overall design, click on the “At a Glance” tab. For a more detailed set of step-by-step design calculations click on the “Detailed” tab.
In this example the proposed beam size is adequate since the design ratios for shear, steel flexure and composite flexure are 0.06, 0.73 and 0.26 respectively. The deflection ratio is 0.97. Note that the design can be further optimized if necessary. Since in this case the deflection ratio is the controlling factor, adding more shear studs would help to reduce the deflection.
Base plates are elements required at the end of columns to distribute the concentrated load of the column over a much larger area of the material that supports it. The design of column base plates involves two main considerations: One, spread the load so as to maintain the bearing pressures under the allowable values, and the second is with the connection, or anchorage, of the base plate and column to the concrete foundation.
The program performs the elastic design of a column steel base plate resting on a concrete support and subjected to any combination of axial load and bending moment, including uplift loading. The moment is assumed acting about the strong axis of a steel column welded to the plate. In addition, this program computes and checks the maximum bearing stress on the support, as well as the tension and shear forces per rod. The column may be eccentrically placed on the concrete support.
For axially loaded base plates, such as those in frames assumed to be pinned at the base, the program is based on either the cantilever model or the Thornton method covered in the AISC Manual 14th Edition.
For base plates with moment, two design theories are considered:
a) For plates assumed rigid, the strain compatibility is enforced in accordance with the Blodgett method (“Design of Welded Structures”).
b) For plates assumed flexible, the strain compatibility is ignored in accordance with the DeWolf method (“AISC.Design Guides # 1, Second Edition”)
For columns subjected to axial tension or uplift, the Murray method is used.
The anchor rods are designed per the latest provisions of the ACI 318 Appendix D “Anchoring to Concrete”, and includes checks for all failure modes in both tension and shear, interaction effects, and reinforcing design. Shear lugs can be designed as well.
The input data required includes the plate, column and pier dimensions, the distance from rods to center of column, the materials properties and the acting service loads. Select the column properties and the anchor rod material from the built-in databases.
As an example, consider a W10x100 steel column designed to resist a bending moment of 40 k-ft and an axial load of compression of 60 k and a shear force of 10 k, welded to a 17″x17″ plate. Design the base plate thickness and check the bearing stresses on a 25″x25″ pier. In addition, design the anchorage using F1554-36 anchor rods.
The plate size is adequate since the maximum bearing stress is 65% of the allowable bearing stress for that pier. The plate thickness required is 1″ and the rod embedment length is 12″ with additional reinforcement. The combined tension-shear stress for the anchor rods is 97% of the allowable value, therefore the design is correct.
ASDIP generates a graphical view of the designed base plate and the resulting bearing pressures and anchor rod forces, as well as the breakout areas in tension and shear, as shown.