Patent ID: 8898907

Claim:
A system for on-site narrow-gap Electroslag-welded beam flange moment connection between vertical column flanges for construction of buildings, wherein the full force developed by a beam flange is transferred to a block formed by a horizontal beam web and two doubler plates through a vertical column web and two doubler plates, the system comprising: a) at least two vertical column flanges, each vertical column flange comprising at least one vertical column web block with two vertical column doubler plates shop welded on either side of the vertical column web block; b) at least one horizontal beam comprising two ends, the at least one horizontal beam positioned between the at least two vertical column web blocks to define two welding gaps, each horizontal beam end comprising a horizontal beam web block and two horizontal beam doubler plates shop welded on either side of the horizontal beam web block, wherein each horizontal beam doubler plate comprises a flush outer end communicating with the welding gap and an equally sloped concave inner end ending in a radius; c) at least one horizontal beam erection support assembly, comprising a sump, wedges, and a jack screw assembly for each vertical column web block, and wherein the at least one horizontal beam erection support assembly is shop welded to a side of the vertical column web block at the horizontal beam-to-column moment connection location; d) means for Electroslag welding within the welding gap between each vertical column web block and each horizontal beam end; and e) computer controlled integrated welding system means for controlling means for Electroslag welding within the welding gap between each vertical column web block and each horizontal beam end; wherein the slope of the horizontal beam doubler plate is optimized to provide even shear stress distribution on a high deposition, submerged arc-weld length by determining a maximum bending moment generated by the horizontal beam and determining a maximum allowable bending moment through the horizontal beam web and two horizontal beam doubler plate thicknesses, whereby the full force developed by the horizontal beam flange is transferred to the block formed by the horizontal beam web and two horizontal beam doubler plates and through the vertical column web and two vertical column doubler plates.