Beam188提供了截面相关参数（面积，位置，分布函数，导数等等）可以通过SECTYPE and SECDATA命令使用于定义截面。每个截面假定由预定的9个节点单位组成。下图列举了通过矩形子项和通道子项建立模型，每个截面单元有4个积分点，每个积分点可设置独立的材料属性。
Figure 188.4 Cross-Section Cells 图188.4：Beam188截面单元格
BEAM188 provide options for output at the section integration points and/or section nodes. You can request output only on the exterior boundary of the cross-section. (PRSSOL prints the section nodal and section integration point results. Stresses and strains are printed at section nodes, and plastic strains, plastic work, and creep strains are printed at section integration points.)
Beam188提供在积分点和界面节点输出的选项。你可以要求仅在截面的外表面输出。（PRSSOL 打印截面节点和截面积分点结果。应力和应变在截面的截面打印，塑性应变，塑性作用，蠕变应力在截面的积分点输出）。
When the material associated with the elements has inelastic behavior or when the temperature varies across the section, constitutive calculations are performed at the section integration points. For more common elastic applications, the element uses precalculated properties of the section at the element integration points. However, the stresses and strains are calculated in the output pass at the section integration points.
当与单元相关的材料有非弹性的行为或者当截面的温度有变化，基本计算在截面的积分点上运行。对于更多的常见的弹性的运用，单元运用预先计算好的单元积分点上的截面属性。无论如何，应力和应变通过截面的积分点输出来计算。
If the section is assigned the subtype ASEC, only the generalized stresses and strains (axial force, bending moments, transverse shears, curvatures, and shear strains) are
available for output. 3-D contour plots and deformed shapes are not available. The ASEC subtype can be displayed only as a thin rectangle to verify beam orientation.
如果截面指定为ASEC 子项，仅仅广义的应力和应变（轴力、弯距、横向剪切、弯曲、剪应力）能够输出。3－D 轮廓线和变形形状不能输出。ASEC 子项仅仅可以作为薄矩形来认定梁的方向。
BEAM188 allow for the analysis of built-up beams, (i.e., those fabricated of two or more pieces of material joined together to form a single, solid beam). The pieces are assumed to be perfectly bonded together. Therefore, the beam behaves as a single member.
Beam188 能够对组合梁进行分析，（例如，那些由两种或者两个以上材料复合而成的简单的实体梁）。这些组件被假设为完全固接在一起的。因此，该梁表现为单一的构件。
The multi-material cross-section capability is applicable only where the assumptions of a beam behavior (Timoshenko or Bernoulli-Euler beam theory) holds.
多材料截面能力仅仅在梁的行为假定（铁木辛哥或者伯努力欧拉梁理论）成立的时候能运用。
In other words, what is supported is a simple extension of a conventional Timoshenko beam theory. It may be used in applications such as:
换言之，支持简单的传统铁木辛哥梁理论的扩展。可应用于以下方面：
? ? ? ? ? ?
bimetallic strips 双层金属带
beams with metallic reinforcement 带金属加固的梁
sensors where layers of a different material has been deposited 位于不同材料组成的层上的传感器
BEAM188 do not account for coupling of bending and twisting at the section stiffness level. The transverse shears are also treated in an uncoupled manner. This may have a significant effect on layered composite and sandwich beams if the layup is unbalanced.
Beam188不会计算在截面刚度水平上的弯距和扭距的耦合。横向的剪切也作为一个独立的量来计算。这对于分层的组合物和夹层量可能会有很大的影响，如果接头处不平衡。
BEAM188 do not use higher order theories to account for variation in distribution of shear stresses. Use ANSYS solid elements if such effects must be considered.
Beam188没有用高阶理论来计算剪切应力的变化，如果这些作用必须考虑的话，就需要运用ANSYS 实体单元。
Always validate the application of BEAM188 for particular applications, either with experiments or other numerical analysis. Use the restrained warping option with built-up sections after due verification.
要使beam188用于特殊的应用，做试验或者其他的数值分析，合适验证后使用组合截面的约束扭曲的选项。
For the mass matrix and evaluation of consistent load vectors, a higher order
integration rule than that used for stiffness matrix is employed. The elements support both consistent and lumped mass matrices. Use LUMPM,ON to activate lumped mass matrix. Consistent mass matrix is used by default. An added mass per unit length may be input with the ADDMAS section controls. See \Summary\.
对于质量矩阵和一致荷载向量的赋值，将使用到比刚度矩阵使用的规则更高阶的积分规则。单元支持一致质量矩阵和集中质量矩阵。用LUMPM，ON 命令来激活集中质量矩阵。一致质量矩阵是默认使用的。每单位长度的附加质量将用ADDMAS 截面控制来输入，详见\。
Forces are applied at the nodes (which also define the element x-axis). If the
centroidal axis is not colinear with the element x-axis, applied axial forces will cause bending. Applied shear forces will cause torsional strains and moment if the centroid and shear center of the cross-section are different. The nodes should therefore be located at the desired points where you want to apply the forces. Use the OFFSETY and OFFSETZ arguments of the SECOFFSET command appropriately. By default, ANSYS uses the centroid as the reference axis for the beam elements.
在节点（这些截面定义了单元的x 轴）上施加力，如果重心轴和单元的x 轴不是共线的，施加的轴力将产生弯距。如果质心和剪切中心不是重合的，施加的剪切力将导致扭转应力和弯曲。因而需要在那些你需要施加力的位置设置节点，可以使用secoffset 命令中的offsety 和offsetz 自变量。默认的，ansys 会使用梁单元的质心作为参考轴。
Element loads are described in Node and Element Loads. Pressures may be input as surface loads on the element faces as shown by the circled numbers on Figure 188.1: \. Positive normal pressures act into the element. Lateral pressures are input as force per unit length. End \
单元荷载在Node and Element Loads 被描述。压力可能被作为单元表面力被输入，就像图188.1中带圈的数字所示。正的压力指向单元内部。水平压力作为单元长度的力来输入。端部的压力作为力输入。
When KEYOPT(3) = 0 (default), BEAM188 is based on linear polynomials, unlike other Hermitian polynomial-based elements (for example, BEAM4). Refinement of the mesh is recommended in general.
当keyopt（3）＝0 的时候（默认），beam188 基于线性多项式，和其他的基于厄密多项式的单元（例如beam4）不同，一般来说要求网格划分要细化。
When KEYOPT(3) = 2, ANSYS adds an internal node in the interpolation scheme, effectively making this a Timoshenko beam element based on quadratic shape functions. This option is highly recommended unless this element is used as a stiffener and you must maintain compatibility with a first order shell element.
Linearly varying bending moments are represented exactly. The quadratic option is similar to BEAM189, with the following differences:
当keyopt（3）＝2，ansys 增加了一个中间积分点在内插值图标，有效的使得单元成为基于二次型功能的铁木辛哥梁。强烈推荐此选项除非这个单元作为刚体使用，而且必须维持和一阶shell 单元的兼容性。可精确的表现弯距线性变化。二次选项和beam189 相似，有如下的不同：
The initial geometry is always a straight line with BEAM188 with or without the quadratic option.
? 不论是否使用二次选项，beam188 单元最初始的几何总是直线。
? You cannot access the internal node; and thus boundary conditions/loading cannot be specified on those nodes.
? 你不能读取中间节点，所以边界条件/荷载不能在那些节点被指定。
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Offsets in specification of distributed loads are not allowed. Non-nodal concentrated forces are not supported. Use the quadratic option (KEYOPT(3) = 2) when the element is associated with tapered cross-sections.
均布荷载是不允许指定偏移的。不支持非节点的集中力。当单元和契型截面相关应使用二次选项（keyopt （3）＝2）。
Temperatures may be input as element body loads at three locations at each end node of the beam. At each end, the element temperatures are input at the element x-axis (T(0,0)), at one unit from the x-axis in the element y-direction (T(1,0)), and at one unit from the x-axis in the element z-direction (T(0,1)). The first coordinate temperature T(0,0) defaults to TUNIF. If all temperatures after the first are
unspecified, they default to the first. If all temperatures at node I are input, and all temperatures at node J are unspecified, the node J temperatures default to the corresponding node I temperatures. For any other input pattern, unspecified temperatures default to TUNIF.
温度可以作为单元的体力在梁的每个端部节点的三个位置输入，单元的温度在单元的x 轴被输入（T（0，0）,和在离开x 轴一个单元长度的y 轴（T（1，0））， 和在离开x 轴一个单元长度的z 方向（T（0，1））。第一坐标温度T（0，0） 默认是TUNIF。如果所有的温度在第一次以后是没有被指定，那么它们默认的就为第一次输入的温度。如果所有i 节点的温度均输入了，j 节点的都没有指明，那么j 节点的温度默认的是等于i 节点的温度。对于其他的输入模式，没有指明的温度默认的是TUNIF。