Elastic-plastic joint elements

This problem contains basic test cases for one or more Abaqus elements and features.

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ProductsAbaqus/StandardAbaqus/Aqua

Elements tested

JOINT2D

JOINT3D

Problem description

A four-step single-element test is performed for two-dimensional and three-dimensional joint elements. The tests include conical and cylindrical cross-sections, with both diagonal and fully populated elastic stiffness material cases. The behavior of the joint elements is defined in a local coordinate system with the results output in the same coordinate system.

Seven different spud can models are used:

  1. Two-dimensional cylindrical spud can, D = 1.6, with general moduli, k1111 = 2000, k1122 = −1000, k2222 = 3000, k1112 = −2000, k2212 = 0.0, k1212 = 6000.

  2. Two-dimensional cylindrical spud can, D = 1.25, with spud can moduli Gν⁢ν = 840.0, Gh⁢h = 1643.0, Gr⁢r = 2150.4, Poisson's ratio, ν = 0.3.

  3. Two-dimensional conical spud can, D = 1.25, θ = 60° with spud can moduli and Poisson's ratio as in Case b, an initial embedment of 0.5 m (less than critical embedment).

  4. Two-dimensional conical spud can, D = 1.25, θ = 60° with spud can moduli and Poisson's ratio as in Case b, an initial embedment of 2.5 m (greater than critical embedment).

  5. Three-dimensional cylindrical spud can, D = 1.1, with general moduli, k1111 = 1000, k1122 = 0.0, k2222 = 2000, k1133 = 0.0, k2233 = −1200, k3333 = 3000, k1112 = 0.0, k2212 = 0.0, k3312 = 0.0, k1212 = 5000, k1113 = 0.0, k2213 = 0.0, k3313 = 1000, k1213 = 0.0, k1313 = 6000, k1123 = 0.0, k2223 = 1000, k3323 = 0.0, k1223 = 0.0, k1323 = 0.0, k2323 = 2000.

  6. Three-dimensional cylindrical spud can, D = 1.5, with spud can moduli, Gν⁢ν = 700, Gh⁢h = 1095.2, Gr⁢r = 4666.3, torsional elastic spring stiffness kt = 5000, Poisson's ratio, ν = 0.3.

  7. Three-dimensional conical spud can, D = 1.5, θ = 60°, with spud can moduli Gν⁢ν = 202.1, Gh⁢h = 474.3, Gr⁢r = 176.83, torsional elastic spring stiffness kt = 4500, Poisson's ratio, ν = 0.3, D = 1.5, initial embedment = 0.321 (less than critical).

Four additional elements test field variable dependence of the material properties. At the specified values of the field variables, these elements have the properties of models a, b, e, and f.

Boundary conditions and loading

In the first step both the base node and the tip node are subjected to prescribed displacements and rotations. In the second step the previous boundary conditions are removed, and the base node is displaced by prescribing displacements and rotations. The tip node is free to move and should follow the base node for this case. In the third step the base node is fixed, and the tip node is subjected to concentrated forces and moments. The fourth step is a perturbation step about the previous step, with loads perturbed by 50% of those in the previous general step.

Results and discussion

The results obtained match the analytical results.

Input files

exepxlx1.inp

Linear elastic tests for elastic-plastic joint elements.