Truss Elements ============== Truss Elements -------------- .. _Truss1d: Truss 1D element ~~~~~~~~~~~~~~~~ Represents linear isoparametric truss element in 1D. The elements are assumed to be located along the x-axis. Requires cross section area to be specified. The element features are summarized in :numref:`truss1dsummary`. .. table:: truss1d element summary :name: truss1dsummary +--------------------------+----------------------------------------------------------------------------------------------+ | Keyword | truss1d | +--------------------------+----------------------------------------------------------------------------------------------+ | Description | 1D truss element | +--------------------------+----------------------------------------------------------------------------------------------+ | Unknowns | Single dof (u-displacement) is required in each node | +--------------------------+----------------------------------------------------------------------------------------------+ | Approximation | Linear approximation of displacement and geometry | +--------------------------+----------------------------------------------------------------------------------------------+ | Integration | Exact | +--------------------------+----------------------------------------------------------------------------------------------+ | Features | Full dynamic analysis support, Full nonlocal constitutive support, Adaptivity support | +--------------------------+----------------------------------------------------------------------------------------------+ | CS properties | Area is required | +--------------------------+----------------------------------------------------------------------------------------------+ | Loads | Body loads are supported. Boundary loads are not supported in current implementation | +--------------------------+----------------------------------------------------------------------------------------------+ | Status | Reliable | +--------------------------+----------------------------------------------------------------------------------------------+ | Tests/Examples | `sm/con2dpm8.in | | | `_, | | | `sm/con2dpm5.in | | | `_, | | | `sm/isoasymm01.in | | | `_, | | | `partests/dyn_bar03/dyn_bar03.oofem.in `_, `partests/dyn_bar03/bar03.statics.oofem.in | | | `_, `sm/Mises02.in | | | `_, `sm/idm02.in | | | `_, `sm/idm03.in | | | `_, `sm/idm04.in | | | `_, `sm/idm05.in | | | `_ (and 9 more) | +--------------------------+----------------------------------------------------------------------------------------------+ .. _Truss2d: Truss 2D element ~~~~~~~~~~~~~~~~ Two node linear isoparametric truss element for 2D analysis. The element geometry can be specified in (x,z), (x,y), or (y,z) plane. The element features are summarized in Table :numref:`truss2dsummary`. .. tikz:: Truss2d element in (x,z) plane. \begin{tikzpicture}[scale=7,>=stealth] \tikzstyle{elemnode} = [draw=black,thick,fill=white,circle,inner sep=1] \newcommand{\trusslength}{0.5}; \draw[->] (-0.05,0) -- (0.7,0) node[above left,at end] {$x_g$}; \draw[->] (0,-0.05) -- (0,0.5) node[below right,at end] {$z_g$}; \draw[very thick] (0.1,0.1) -- +(30:\trusslength) node[elemnode,at start] {} node[at start,yshift=2,above left] {1} node[elemnode,at end] {} node[at end,yshift=2,above left] {2}; %\draw[dotted,->] (0.1,0.1)++(-30:0.42) -- +(-30:0.1) node[below] {$X_1$}; %\draw[dotted,->] (a)++(-30-90:0.02) -- +(-120:0.1) node[right] {$Z_1$}; \end{tikzpicture} .. table:: truss2d element summary :name: truss2dsummary +--------------------------+----------------------------------------------------------------------------------------------+ | Keyword | truss2d | +--------------------------+----------------------------------------------------------------------------------------------+ | Description | 2D truss element | +--------------------------+----------------------------------------------------------------------------------------------+ | Specific parameters | :optelemparam:`cs{in}` | +--------------------------+----------------------------------------------------------------------------------------------+ | Parameters | :param:`cs`: this parameter can be used to change default definition plane. The supported | | | values of :param:`cs` are following: 0 for (x,z) plane (default), 1 for (x,y) plane, and 3 | | | for (y,z) plane. | +--------------------------+----------------------------------------------------------------------------------------------+ | Unknowns | Two dofs representing displacements in definition plane are required in each node. The | | | element can be used in different planes, default definition plane is (x,z). The parameter | | | :param:`cs` can be used to change default definition plane. | +--------------------------+----------------------------------------------------------------------------------------------+ | Approximation | Linear approximation of displacements and geometry. | +--------------------------+----------------------------------------------------------------------------------------------+ | Integration | Exact. | +--------------------------+----------------------------------------------------------------------------------------------+ | Features | Full dynamic analysis support. Full nonlocal constitutive support. | +--------------------------+----------------------------------------------------------------------------------------------+ | CS properties | cross section area should be provided. | +--------------------------+----------------------------------------------------------------------------------------------+ | Loads | Edge loads are supported, Edge number should be equal to 1 | +--------------------------+----------------------------------------------------------------------------------------------+ | Status | Reliable | +--------------------------+----------------------------------------------------------------------------------------------+ | Tests/Examples | `sm/linear_constraint_1.in | | | `_, | | | `sm/linear_constraint_2.in | | | `_, | | | `sm/linear_constraint_3.in | | | `_, | | | `sm/patch160.in | | | `_, | | | `partests/dyn_bar01/dyn_bar01.oofem.in `_, `sm/trussb3_creep.in | | | `_, | | | `sm/trussb3_relax.in | | | `_, | | | `sm/steelRelaxMat2.in | | | `_, | | | `sm/rotated_1.in | | | `_, | | | `sm/rotated_2.in | | | `_ (and 7 more) | +--------------------------+----------------------------------------------------------------------------------------------+ truss2d element summarytruss2dsummary .. _Truss3d: Truss 3D element ~~~~~~~~~~~~~~~~ Two node linear isoparametric truss element for 3D analysis. The element geometry is specified in (x,y,z) space. The element features are summarized in Table :numref:`truss3dsummary`. .. tikz:: Truss3d element in (x,y,z) space. \begin{tikzpicture}[scale=7,>=stealth] \tikzstyle{elemnode} = [draw=black,thick,fill=white,circle,inner sep=1] \newcommand{\trusslength}{0.5}; \begin{scope} \draw[->] (-0.05,0,0) -- (0.5,0,0) node[at end, below] {$x_g$}; \draw[->] (0,-0.05,0) -- (0,0.5,0) node[at end, below right] {$y_g$}; \draw[->] (0,0,-0.05) -- (0,0,0.5) node[at end, right] {$z_g$}; \end{scope} \draw[very thick] (0.1,0.1) -- +(30:\trusslength) node[elemnode,at start] {} node[at start,yshift=2,above left] {1} node[elemnode,at end] {} node[at end,yshift=2,above left] {2}; %\draw[dotted,->] (0.1,0.1)++(-30:0.42) -- +(-30:0.1) node[below] {$X_1$}; %\draw[dotted,->] (a)++(-30-90:0.02) -- +(-120:0.1) node[right] {$Z_1$}; \end{tikzpicture} .. table:: truss3d element summary :name: truss3dsummary +--------------------------+----------------------------------------------------------------------------------------------+ | Keyword | truss3d | +--------------------------+----------------------------------------------------------------------------------------------+ | Description | 3D truss element | +--------------------------+----------------------------------------------------------------------------------------------+ | Unknowns | Three displacement DOFs (in x, y, and z directions) are required in each node. | +--------------------------+----------------------------------------------------------------------------------------------+ | Approximation | Linear approximation of displacements and geometry. | +--------------------------+----------------------------------------------------------------------------------------------+ | Integration | Exact. | +--------------------------+----------------------------------------------------------------------------------------------+ | Features | Full dynamic analysis support. Full nonlocal constitutive support. | +--------------------------+----------------------------------------------------------------------------------------------+ | CS properties | cross section area should be provided. | +--------------------------+----------------------------------------------------------------------------------------------+ | Status | Reliable | +--------------------------+----------------------------------------------------------------------------------------------+ | Tests/Examples | `sm/nldeidynamic1.in | | | `_, | | | `sm/compoDamMat.in | | | `_, | | | `sm/linkslip02.in | | | `_ | +--------------------------+----------------------------------------------------------------------------------------------+