Steel Connections Optimisation with MasterSeries [Webinar Recording 2024]

Posted on February 13th, 2024 in Webinars

Summary

This webinar by MasterSeries Software provides a comprehensive guide to steel connection design, primarily utilising their dedicated software module. The session begins with an overview of various simple and moment connection types, including flexible end plates, fin plates, double angle web cleats, and base plates, detailing their practical applications, benefits, and limitations. A key focus is placed on optimising connection designs for cost-effectiveness and structural integrity, with an emphasis on understanding load paths and strengthening critical components. The latter part of the webinar demonstrates the software's auto-design capabilities and highlights new features, such as Hollow Section beam support and flange toe plates, concluding with a discussion on incorporating sustainability considerations into connection design.

Key Topics

• Steel Connection Design
• MasterSeries Software Features
• Connection Design Examples
• Sustainable Design Practices
• Joint Template Library

Description

This webinar, presented by MasterSeries, focuses on the design and optimisation of steel connections using the MasterSeries connection design module. The presentation uses a 3D SketchUp model of a single-story steel frame to illustrate various connection types and practical considerations.

Core Design Principles and Methodology:

• Connection designs in MasterSeries align with UK best practice guidance, particularly the SCA Green Book Publications.

• The software considers major axis bending moment and shear, as well as axial forces (compression and tension). Minor axis bending and shear are generally not considered, except for specific splice connections.

• Fabrication costs for connections can be significant (up to 30-50% of total fabrication cost), making simpler connections often more economical due to less welding.

Connection Types Available within MasterSeries:

1. Simple Connections (Generally cheaper to fabricate):

    ◦ Flexible End Plate:

        ▪ Used for beam-to-beam or beam-to-column connections. The supported beam is often notched to keep the top flange flush.

        ▪ Can be partial or full depth, with full depth offering higher shear (up to 100% of beam shear) and tying resistance.

        ▪ To Plates (New in MasterSeries 2023): An option to avoid notching beams, potentially easing erection, but generally more expensive and material-intensive. MasterSeries has developed a technical note (with FEA) to guide engineers on its design.

    ◦ Fin Plate:

        ▪ A plate welded to the supporting member, with the supported beam bolted on site.

        ▪ Economical, simple to erect, popular for secondary beams and can accommodate skewed beams and offsets.

        ▪ Offers high tying resistance due to a direct load path.

    ◦ Double Angle Web Cleats:

        ▪ Currently less popular due to requiring bolts in both directions and being unsuitable for skewed connections.

        ▪ Offers advantages like avoiding welding, allowing site adjustments, and being fully demountable for sustainability at end-of-life.

    ◦ Simple Base Plate:

        ▪ Designs base plates for columns of various sections (I, Hollow). Typically involves four holding-down bolts cast in place, outside the section extent, for erection stability.

        ▪ Features include grout (25-50mm) for adjustments and optional shear keys to transfer horizontal loads if bolts and friction are insufficient. The design is effectively the same for simple and moment base plates within the software.

2. Bracing Connections:

    ◦ Generally aim for matching centroids to avoid eccentricities. Bracing is often among the first elements erected for structural stability.

    ◦ Common types include single angle bracing with welded gusset plates and Hollow Section bracing (effective in tension and compression).

    ◦ MasterSeries supports various bracing members (Hollow sections, angles, channels, flats) and connection arrangements.

    ◦ Connections include vertical bracing to beam flange/web, horizontal bracing to beam web (for plan bracing), and vertical bracing to column web/flange.

    ◦ The software can link resultant forces from bracing connections to associated beam and end plate connections.

    ◦ Bracing to Base Plate designs gussets and welds, while the column base plate is designed independently for overall shear and axial forces.

3. Moment Connections (Typically more expensive due to extensive welding):

    ◦ Beam-to-Beam End Plate (Apex): Used in portal frames (e.g., apex) to transfer moment between rafters, often using extended end plates and haunch sections to increase moment capacity.

    ◦ Beam-to-Beam Splice (Bolted Cover Plate): Stiffer than end plate splices, used to manage minor axis bending/shear with bolted cover plates. Recommended at points of minimum bending.

    ◦ Beam-to-Column Flange via End Plate (Portal Eaves): Designs portal eaves rafters, often featuring slopes, extended end plates, and haunches (typically 10% of span length). The software provides suggestions to avoid stiffeners, such as using deeper haunches or stronger column sections.

    ◦ Column-to-Beam: For designs where a column is interrupted by a continuous beam, or a beam sits over a column cap, or a column is supported by a beam. MasterSeries 2023 now supports Hollow Sections for both beams and columns in these connections, as well as column splices.

Sustainability in Connection Design:

• The MasterSeries LCA module accounts for approximately 5% of a steel frame's total carbon emissions.

• Tips for sustainable design include specifying Green Book connections for efficient fabrication, using bolted connections over welded for reusability/recyclability, preferring standard bolts over HSFG bolts, and using fillet welds over full penetration butt welds where adequate.

• While saving carbon on connections can be challenging due to high associated costs, the webinar suggests that other carbon reduction strategies often correlate with cost savings.

MasterSeries Connection Design Module Demonstration and Features:

• The software features an interactive graphical interface, a property tree for manipulating components, and a detailed calculation area that highlights failing design checks with warnings.

• Design Workflow: Users can select from a Joint Template Library or build connections from scratch. The module uses a component method to calculate resistance, identifying the weakest components (e.g., bolt row in tension, column web in compression) for targeted strengthening.

• Optimisation: Demonstrated by adding haunches to extend the lever arm, increasing bolt rows, and incorporating column stiffeners to resolve failures under applied loads. The software can handle multiple load cases, including uplift and reverse moments.

• Auto Design: An automated function that optimises connections across all specified load cases.

• Joint Template Library Enhancements: Allows users to create custom company or project templates to standardise design workflows and ensure consistency, which are also shareable.

Latest Developments in MasterSeries 2023:

• Base Plate Connection: Implements Eurocode EN 1992-4 anchor bolt calculation, which handles concrete edge conditions (pull-out, edge shear) and allows for specifying side steel.

• Hollow Section Beams: Beam-to-column and column-to-beam moment connections now fully support SHS/RHS beams and columns.

• Beam-to-Beam Flexible End Plate with To Plate Option: A new feature requested by users, allowing a flange to plate on the outside face of the supported beam.

MasterSeries offers free trials and demos for interested users.