Connections Frame - Bolted diagonals (esasd.06)



The esasd.06 module "Connections Frame - Bolted diagonals" performs the design and verification of connections of bolted diagonals (i.e. bracing, truss elements). As the methods pertain to structures with steel frames, the analysis and design is performed according to Eurocode 3. The diagonals may be connected by means of a gusset plate or be directly attached to the column. Checks are performed on the bolt resistance, and the resistance of connected elements against rupture, (block-)shear and bearing. Using automatic optimisation, the minimum required number of bolts may be calculated. Support for diagonals that are directly connected to primary load bearing elements is useful in the design of structures such as tower masts and storage racks.

Design of bolted bracing and other diagonal elements according to EN 1993.
Checks for the resistance of bracing elements, bolts and gusset plates.
Automatic optimisation to determine the optimal number of bolts.
Full integration with the main graphical user interface.
Simple design, fast assessment, detailed output, clear drawings (module esadt.02 is required) within several clicks.

Connection types

The design and analysis of two connection types are supported:

  • Diagonals attached to a gusset plate via bolts; gusset plates are welded to the column. The cross-section of the diagonal may be an angle, channel, I-section;
  • Diagonals connected directly to the supporting member (has to be an angle section). The diagonal element may be an angle, channel, RHS, cold-formed section;
  • The connection at the diagonal end is always bolted. One or two (non-)staggered bolt-rows may be used.

Assistance in an improved design workflow

Connections to diagonal elements are defined based on limited user input:

  • thickness of gusset plate;
  • weld throat thickness (welds are at column side);
  • bolt size and class;
  • number and distribution of bolts - number of rows (1 or 2), number of bolts per bolt-row, bolt pitch and edge distances in the gusset plate and in the diagonal(s).

All code-related design parameters are included by default in the calculation:

  • safety factors;
  • minimal/maximal bolt spacing and edge distances;
  • minimal weld size;
  • a library of bolts,nuts and washers is provided, with material and geometrical properties;
  • SCIA Engineer allows for all these properties to be edited by the user, if required.

Connections may be copy-pasted to other nodes or elements in the structure.

Calculation, reporting and visualisation

The normal force per diagonal element (calculated during the analysis of the structure) is taken into account in the design:

  • The user may specify whether only tensile, or both tensile and compressive normal forces should be considered in the connection design;
  • Checks for the strength of different connection components are performed according to EN 1993-1-8 and EN 1993-1-1;
  • An optimisation of the initial input may be performed so that all components in the connection comply with the code requirements;
  • The results of the calculation and the connection layout may be included in the project documentation;

List of checks

The bolted diagonals are designed according to Eurocode 3: Design of steel structures. Part 1-8: Design of joints. The following resistances are controlled:

  • Bolt shear resistance;
  • Bolt bearing resistance (in diagonals/gusset plate);
  • Bolt slip resistance (for slip-critical joints);
  • Rupture or shearing in the gross section of the diagonal(s) and gusset plate;
  • Rupture or shearing in net section of the diagonal(s) and the gusset plate.
  • The size of the weld between gusset plate and the main supporting element is calculated automatically.