Hello all,
I am checking some old deep web girders for additional loads. I am familiar with AISC 13th Ed. Eq's J10-2, J10-3 for Web Local Yielding and the other local web limit states and know that these equations are used for concentrated loads coming from bearing situations (can occur at ends or within the span). This is further reinforced within the commentary of the code for this section. This portion of the code is fairly easy to interpret however I am dealing with a situation of extremes (in terms of dimensions) that has had me thinking.
Knowing that the equation deals with concentrated loads from bearing loads, what about concentrated loads from shear connections? Such as a transverse beam carrying a high shear load that ties directly into a very deep girder? This is not a bearing load as it is connected by lets say a shear tab or double angle connection...Yet lets say that we have a plate girder that is 100" deep and that this 8" transverse beam ties near the top of the plate girder and carries a significant load...how can you check the local effects from the load on the plate girder web. I understand that the beam framing into the girder is providing lateral restraint however since we still have 92" of web (100" plate girder-8" transverse beam) below the shear connection shouldn't there be the need to check for local effects on the plate girder web below the connection point? Or is this assumed to be taken into account by intermediate stiffeners (not bearing stiffeners)and their respective checks?
The original design has bearing stiffeners under concentrated loads that are applied to the top of the flange (small loads) of the plate girder however no bearing stiffeners are provided under transverse beams that tie directly into the plate girder web (higher loads). Is this taking the code too literally or am I missing something? Please help as I have exasperated my options by looking through texts and the internet...thank you all in advance!
I am checking some old deep web girders for additional loads. I am familiar with AISC 13th Ed. Eq's J10-2, J10-3 for Web Local Yielding and the other local web limit states and know that these equations are used for concentrated loads coming from bearing situations (can occur at ends or within the span). This is further reinforced within the commentary of the code for this section. This portion of the code is fairly easy to interpret however I am dealing with a situation of extremes (in terms of dimensions) that has had me thinking.
Knowing that the equation deals with concentrated loads from bearing loads, what about concentrated loads from shear connections? Such as a transverse beam carrying a high shear load that ties directly into a very deep girder? This is not a bearing load as it is connected by lets say a shear tab or double angle connection...Yet lets say that we have a plate girder that is 100" deep and that this 8" transverse beam ties near the top of the plate girder and carries a significant load...how can you check the local effects from the load on the plate girder web. I understand that the beam framing into the girder is providing lateral restraint however since we still have 92" of web (100" plate girder-8" transverse beam) below the shear connection shouldn't there be the need to check for local effects on the plate girder web below the connection point? Or is this assumed to be taken into account by intermediate stiffeners (not bearing stiffeners)and their respective checks?
The original design has bearing stiffeners under concentrated loads that are applied to the top of the flange (small loads) of the plate girder however no bearing stiffeners are provided under transverse beams that tie directly into the plate girder web (higher loads). Is this taking the code too literally or am I missing something? Please help as I have exasperated my options by looking through texts and the internet...thank you all in advance!
