Shakedown of Grids

The simple shakedown theory that employs the assumptions of plastic design is extended to grids in the paper. The grids are continuous over supports of fixed elevation and contain three main girders and three cross beams per span. Torsion in the grid is ignored. After the theoretical analysis, an example is treated for clarification. It is found that the shakedown load for the grid falls between the load which initiates yielding, and the load at which a fully plastic mechanism is formed.