Moment Influenced Design Acceptance
Moment transfer joints are rigid and full / partial strength joints.
For rigid joints, frontal plate and welded joints are classified according to the rotational rigidity and the rotational stiffness ratios are defined in the earthquake code depending on the ductility level.
General Account Rules for Head Plate Connections
The strength of the frontal plate joint is determined by the assumption that the tensile force of the bolts in one head is controlled by the crushing limit state under the pressure force in the other.
If there is no axial load on the joint, the total tensile and compressive forces are equal and opposite in both heads, so that the total force creates a force pair.
For ease of calculation, it is accepted that the center of rotation is in the center of the pressure head.
Overlay Plate Column / Beam Attachment General Account Rules
In order to be suitable for the design under reversible effects such as earthquake effects, symmetrical and equal number of bolts are used on both heads and body. ideCAD does not allow asymmetrical structure during modeling.
While it is assumed that the heads bear the moment effect and the body the shear force, the axial force is equally shared between both heads.
While space is left in between the beam inserts, it may or may not be left in the column joints.
TBDY 2018 Moment Influenced Design Acceptance
Depending on the ductility level, the joints that are determined to provide a relative angle of translation of at least 0.04 or 0.02 radians within the scope of TBDY 2018 9B.1 must be used. These joints are front plate joints and header plate joints designed in ideCAD Statik.
If the design of the joints is desired to be obtained with TBDY 2018, the YDKT method is mandatory in accordance with the earthquake regulations.
The required bending moment strength M end and the required shear strength V end on the column face of the joints are calculated over the plastic joints at the end of the beam. The formulas in the image below are used in the account.
The V- end used in the dimensioning of the joint is determined according to the equation in the above image by summing the shear force determined on the basis of the yield state and the shear force calculated from the combination of 1.2G + 0.5Q + 0.2S on the plastic joint at the end of the beam .
Plastic joint length is specified separately for each joint in TBDY 2018 and automatic calculation is made in accordance with these rules. Details will be given in each respective combination.
The shear strength required for the shear zone is calculated by using the column shear force generated by the possible plastic moments of the beams connecting to the column.
Icons
Cpr: Stiffening in the joint, etc. a coefficient that takes into account the circumstances and is used to calculate the maximum possible bending moment strengthÂ
Fu: Structural steel characteristic tensile strengthÂ
Fy: Characteristic yield stress in structural steel
lh: The distance of possible plastic hinge point at the beam ends to the column face
ln: Beam span between possible plastic hinge points at the beam ends
Mpr: Possible bending moment capacity
Mpri: Possible bending moment capacity at the left end i of the beam
Mprj: Possible bending moment capacity at the right end j of the beam
Muc: Required bending moment strength of the joint at the face of the column
Ry: ratio of possible yield stress to characteristic yield stress
Vd: Simple beam shear force arising from vertical loads at the plastic hinge point of the beam.
Vuc: Required shear strength of the joint at the face of the column