# Elements

Alpaca4d provides different finite element types to model 1D, 2D and 3D structural components.\
The main Grasshopper components are **Line to Beam**, **Mesh to Shell** and **Brick Element**.

## Beam elements – Force Beam Column

The **Force Beam Column** component converts Rhino curves into **Timoshenko beam elements**.

* **Usage**
  * Use beams when one dimension (length) is much larger than the cross‑section dimensions.
  * Suitable for frames, trusses, columns, beams, braces and similar members.
* **Behaviour**
  * Timoshenko formulation → includes both bending and shear deformations.
  * The cross‑section is defined separately and can be oriented using the `orientSection` input.
  * The `beamType` option allows you to release end rotations and/or forces, e.g. to create axial‑only (truss) elements.

## Shell elements – ASDShell

The **ASDShell** component converts mesh faces into **shell elements**.

* **Usage**
  * Use shells when one dimension (thickness) is much smaller than the in‑plane dimensions.
  * Typical applications: slabs, walls, plates, folded shells, roofs, tanks.
* **Behaviour**
  * Triangular faces are converted to **ASDShellT3** elements.
  * Quadrilateral faces are converted to **ASDShellQ4** elements.
  * The element thickness and material are defined through the assigned shell section.

## Brick elements – SSPbrick

The **SSPbrick** component converts hexahedral solids into **3D brick elements** (e.g. `SSPbrick` ).

* **Usage**
  * Use bricks for fully 3D stress states, such as foundations, solid walls, blocks, soil volumes, or regions with strong 3D effects.
* **Behaviour**
  * The input must be a hexahedral mesh (six‑faced solid with quadrilateral faces).
  * Creating high‑quality hex meshes can be challenging; the **MeshSeriesToBrick** utility component can help generate simple brickable volumes from a series of meshes.

In practice, you will usually **combine** these element types in the same model:\
beams for the main frame, shells for slabs and walls, and bricks for local 3D regions where needed.