"Optional title"
entype, enid, tid, $tol$
$R$, $h$, $m$, $k$, $F_t$, $F_s$, $W_t$, $W_s$

Parameter definition

Command ID
Entity type of sheets to be connected
options: P, PS, ALL
Entity ID of sheets to be connected
Table ID of spot weld list
Maximum allowed distance between surfaces to be connected
Spot weld radius
Spot weld height
Spot weld mass
Spot weld stiffness
Failure force - tear
Failure force - shear
Energy absorption - tear
Enery absorption - shear


This command is used to define spot weld connectors between two or more layers of material. The spot weld ID's and positions are defined in a TABLE (see example below). The formulation is penalty based and a spot weld mass $m$ is required in order to define the critical spot weld time step size.

The height parameter $h$ is used to identfy the correct sheets in cases where more than two layers are welded together. Apart from that both $h$ and $R$ are only used for visualization purposes.

The load carrying capacity of a spot weld is direction dependent. $F_t$ is the maximum force in pure vertical loading and $F_s$ is the capacity in pure shear. For directions in-between the capacity $F_{max}$ is defined as:

$\displaystyle{ F_{max}(\alpha) = F_t \mathrm{cos}^2 \alpha + F_s \mathrm{sin}^2 \alpha}$

The definition of $\alpha$ is shown in the figure below. A similar interpolation is assumed for the energy absorption (ductility). The elongation at complete fracture $\delta_{max}$ is adjusted such that:

$\displaystyle{ W(\alpha) = \frac{1}{2} F_{max} \delta_{max} = W_t \mathrm{cos}^2 \alpha + W_s \mathrm{sin}^2 \alpha}$
Spot weld connection between two sheets
Spot weld connection between two sheets


Spot welded steel sheets

Two steel sheets with six spot welds.

*UNIT_SYSTEM SI *COMPONENT_BOX "upper sheet" 1, 1, 20, 10, 1 -0.025, -0.025, 0.0, 0.075, 0.025, 0.002 *COMPONENT_BOX "lower sheet" 2, 2, 20, 10, 1 -0.075, -0.025, -0.002, 0.025, 0.025, 0.0 *CHANGE_P-ORDER ALL, 0, 3 *MAT_LIBRARY "Docol 600 DL_SSAB_G.Gruben(2015)_DE_ISO_YVM_SR", 1 *PART "upper sheet" 1, 1 "lower sheet" 2, 1 *CONNECTOR_SPOT_WELD "spot weld (P1 to P2)" 1 PS, 12, 1000, 1.0e-4 0.002, 0.004, 1.0e-4, 1.0e7, 2.0e3, 3.0e3, 2.0, 4.0 *TABLE "spot weld (P1 to P2)" 1000, 4 1, -0.01, -0.015, 0.0 2, -0.01, 0.0, 0.0 3, -0.01, 0.015, 0.0 4, 0.01, -0.015, 0.0 5, 0.01, 0.0, 0.0 6, 0.01, -0.015, 0.0 *SET_PART 12 1, 2 *END