Lug angles are occasionally utilised to shorten connection lengths. The lug angle connection with a single or channel type tension member is shown in the diagram below.
The rivets connecting the gusset plate and the lug angle will carry less stress than the rivets joining the main member and the gusset plate due to the possibility of distortion of the outstanding leg of the lug angle.
The India Standard IS 800 specifies the following for the design of lug angles:
Lug angles connecting a channel-shaped member should be positioned symmetrically with regard to the member’s section as much as practicable.
The lug angles and their connections to the gusset or any other supporting member in the case of angle members should be capable of developing a strength not less than 20% greater than the force in the outstanding leg of the angle, and the lug angle member’s attachment should be capable of developing a strength 40% greater than that force.
The lug angles and their connections to the gusset or any other supporting element in channel sections should be capable of creating a strength of at least 10% greater than the force.
The lug angles’ attachment to the member should be capable of creating a strength 20 percent greater than that force.When mounting the lug angle to the gusset or another supporting part, no fewer than two bolts or rivets should be used.
The lug angle’s effective connection should, as far as practicable, finish at the end of the member linked, and the lug angle’s attaching to the member should preferably begin before the member’s direct connection to the gusset or other supporting member.
When using lug angles to join angle members, the entire area of the member should be considered effective, i.e.
A(net) = Gross area – deduction for holes
The lug angle is a short-length angle section that joins the outstanding legs of an angle section or member to the gusset plate.
It shortens the connection to the gusset plate while also lowering the shear lag effect.
When the lug angle is applied, the main angle’s disconnected length functions as a connected leg, and the entire cross-section area begins to resist the stress. As a result, the shear lag effect is reduced, and the tension member’s efficiency improves.Extra gauge line is provided by the lug angle to suit the number of bolts.
Tension splices are cover plates that are utilised on both sides of butt joined components.
When the length of section provided is less than the length of tension member required, the tension member is spliced.
Splicing members of various thicknesses necessitates packing to fill the gap.The spliced area should be slightly larger than the combined member’s.
It’s especially useful when the size of a member varies over time.
The lug angle is a tiny piece of angle that connects the members’ outstand legs to the gusset plate. Lug angle is used to shorten the length of the connection to the gusset plate and reduce shear lag.
Due to the additional bolt holes in the projected member, the usage of lug angle reduces the net area of main members. This net area reduction should not be extreme. More than two bolts are utilised to connect the lug angle to the member or gusset plate.