# Split Set / Swellex

**Split Set** and **Swellex** bolt types in **RocPlane** allow you to model a fully bonded frictional bolt type, as shown in the figure below.

**Split Set** and **Swellex** are presented as two different bolt types in **RocPlane**, for modeling convenience. However, the two bolt types are implemented in exactly the same way in the analysis. The only difference between the two selections is that the default **Bond Strength** is higher for **Swellex** than for **Split Set**. This value can of course be changed by the user.

Furthermore, the implementation of the **Swellex / Split Set** models in **RocPlane** is essentially the same as the **Grouted Dowel** model, with the condition that the **Bonded Length** for a **Swellex / Split Set** is always 100%. Except for this difference, the implementation of the **Swellex / Split Set** and **Grouted Dowel** models are the same. For details, see Grouted Dowel Bolts in RocPlane.

**NOTE:** To model a **Swellex** or **Split Set** bolt without a face plate, enter **Plate Capacity = 0**.

## Bolt Force Diagram

A **Bolt Force Diagram** for a **Swellex** bolt that exhibits all three failure modes is shown below. If the **Plate Capacity** is less than the **Tensile Capacity**, **Stripping** is a possible failure mode. If the **Bond Capacity** at either end is sufficient to equal the **Tensile Capacity** of the bolt, tensile failure can occur along the middle of the bolt, as shown in the following figure.

**Bolt Force Diagrams** for **Swellex** or **Split Set** bolts with no face plate are shown below (if **Plate Capacity = 0**, the origin of the force diagram is at zero force). For the **Swellex** example, tensile failure is possible due to the relatively high bond strength of **Swellex** bolts. For the **Split Set** example, tensile failure cannot occur because the **Bond Capacity** is not sufficient to equal the **Tensile Capacity** of the bolt. Therefore, only **Stripping** or **Pullout** can occur. Actual **Bolt Force Diagrams** depend on **Bolt Length**, **Bond Strength**, **Tensile Capacity**, and **Plate Capacity**.

*Tensile bolt force diagram for Swellex bolt with no face plate*

*Tensile bolt force diagram for split set with no face plate*