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D. Connection Tags Capacity Checks

The rules for checking the connections are dependent on the whether the connection is typed as moment or shear.

Moment Connections

Shear Capacity Check - The shear capacity for a given beam/column combination present in the ConnectionTagFile.xml is checked against the demand taken as the absolute value of the major axis shear value, Fy, from each of the load cases included and the maximum value reported.

If the shear capacity in the XML file is 207.345 kN, then:

  • when Fy = ±208.0 kN > 207.345 kN, the connection check is failed.
  • when Fy = ±200.0 kN < 207.345 kN, the connection check is passed.

Moment Capacity Check - The moment capacity check for a given beam/column combination is based on both the major axis moment and axial force. For each load case, the maximum demand is taken from the end moment plus the axial force multiplied by a specified alpha factor and compared against the given moment capacity.

If the moment capacity in the XML file is 35.951 kN·m and the tension force factor, alpha, is 0.09565, then demand = |Mz| + α·|Fx|:

  • when Mz = 30 kN·m and Fx = -50 kN, then demand is 30 + 0.09565(50) = 34.7825 kN·m < 35.951 kN·mm, the connection check is passed.
  • when Mz = 32 kN·m and Fx = -50 kN, then demand is 32 + 0.09565(50) = 36.7825 kN·m > 35.951 kN·mm, the connection check is failed.

Shear Connections

The shear capacity for a given beam/column combination present in the ConnectionTagFile.xml is checked against the demand taken as the major axis shear value, Fy, and a proportion of the axial force, Fx, from each of the load cases included and the maximum value reported.

If the shear capacity in the XML file is 15.538 kN and the tension force factor, alpha, is 0.2016, then demand = |Fy| + α·|Fx|

  • when Fy = 12 kN and Fx = -25 kN, then demand = 12 + 0.2016(25) = 17.04 kN > 15.538 kN, the connection is failed.
  • when Fy = 10 kN and Fx = 25 kN, then demand = 10 + 0.2016(25) = 15.04 kN < 15.538 kN, the connection is passed.
Note: There are no moment capacity checks for a shear connection.