## Question

**What coordinate systems are used in midas Civil?**

## Answer

**In midas Civil, there are Global Coordinate System, Element Coordinate System, and Node Local Coordinate System**

The following coordinate systems are used in midas Civil:

Global Coordinate System

Element Coordinate System

Node Local Coordinate System

The Global Coordinate System uses a conventional Cartesian coordinate system with orthogonal X, Y, and Z axes that follow the right-hand rule, denoted by uppercase "X, Y, Z" axes. The nodal data, the data related to the nodes, nodal displacements, and reactions follow the global coordinate system. The global coordinate system is used to define the geometric position of the structure to be analyzed, and the reference point is automatically set at X=0, Y=0, and Z=0 within the program. In Midas Civil, since the vertical direction of the screen is oriented in the global coordinate system Z-axis direction, it is convenient to define the vertical direction of the structure (opposite to the direction of acceleration due to gravity ) parallel to the global coordinate system Z-axis.

The Element Coordinate System uses a Cartesian coordinate system with orthogonal x, y, and z axes that follow the right-hand rule, denoted by lowercase "x, y, z" axes. The element loads, stresses, and most of the data related to the elements follow the element coordinate system.

The Node Local Coordinate System is used to input boundary conditions, such as restraints, boundary springs, enforced displacements, or to calculate and output reactions in an arbitrary direction that does not coincide with the global coordinate system at a node. It uses a Cartesian coordinate system with orthogonal x, y, and z axes that follow the right-hand rule, denoted by "x, y, z" axes.