K4HSS-to-HSS moment connections

HSS-to-HSS moment connections are defined as connections that consist of one or two branch members that are directly welded to a continuous chord that passes through the connection, with the branch or branches loaded by bending moments.

A connection shall be classified as

• (a) A T-connection when there is one branch and it is perpendicular to the chord and as a Y-connection when there is one branch, but not perpendicular to the chord
• (b) A cross-connection when there is a branch on each (opposite) side of the chord

K4.1 Definitions of Parameters

$Z_{b}=$ plastic section modulus of branch about the axis of bending, in. ${ }^{3}\left(\mathrm{~mm}^{3}\right)$

K4.2 Round HSS

The available strength of round HSS-to-HSS moment connections within the limits of Table K4.1A shall be taken as the lowest value of the applicable limit states shown in Table K4.1.

K4.3 Rectangular HSS

The available strength, $\phi P_{n}$ and $P_{n} / \Omega$, of rectangular HSS-to-HSS moment connections within the limits in Table K4.2A shall be taken as the lowest value obtained according to limit states shown in Table K4.2 and Chapter J.

User Note: Outside the limits in Table K4.2A, the limit states of Chapter J are still applicable and the applicable limit states of Chapter K are not defined.