This Tcl code creates full-scale three-dimensional continuum model of Meloland Road Overpass (MRO) located in El-Centro, California. The code is generic and can be modified to simulate any two-span bridge with a structure similar to MRO.  Ground motion can be applied at the model base in two horizontal directions. Please read the article about base boundary condition. You can assign either rigid base or compliant base boundary conditions.

The FE mesh that the Tcl file creates is shown in Figure 1 below. The code is capable of creating all structural elements of the bridge including abutment walls, abutment piles, pier, piles underneath the pier and the bridge deck. Soil nonlinear hysteretic behavior is simulated. The current version simulates dry soil condition only.

The Tcl file can be downloaded from the following link:   MRO-Continuum-model.zip

It is important to understand how the nodes and elements have been numbered in the code. The numbering starts from 1 at (x=0, y=0, z=0) and increases with an increment of 1 in direction +Z, then when it reaches the maximum node/element, it increments in direction +Y and finally in direction +X till last node/element is reached. The nodes and elements of embankments are created after creating the foundation soils with the same numbering procedure described above.

For further information about the model please read my journal paper; “Nonlinear dynamic analysis of Meloland Road Overpass using three-dimensional continuum modeling approach”.