The goal of the study was to figure out the best way to calculate the effective width of steel-concrete composite box girder bridges. The researchers used computer software to analyze 160 different bridge models and looked at factors like the shape of the bridge, the height of the road, the length of the bridge, and how the materials were arranged. They found that the distribution of stress at the connection between the steel and concrete is crucial for determining the correct effective width. Based on their findings, they suggested a new method for calculating the effective width of these bridges.