ABAQUS中的三种混凝土本构模型(20200706140516)
abaqus钢筋混凝土参数
abaqus钢筋混凝土参数
Abaqus 是一款常用的有限元分析软件，常用于工程领域的结构力学
分析、流体力学分析等方面。
在使用 Abaqus 进行钢筋混凝土结构的
分析时，需要设置一些参数才能获得准确的计算结果。
1. 材料参数
钢筋和混凝土是钢筋混凝土结构中重要的材料。
在使用 Abaqus 进行
分析时，需要设置钢筋和混凝土的材料参数，例如弹性模量、泊松比、拉伸强度、压缩强度等。
这些参数是计算混凝土结构的重要基础。
2. 单元类型
在进行分析时需要选择所需的单元类型，钢筋混凝土结构中常用的单
元类型有三种：梁单元、壳单元和实体单元。
不同的单元类型适用于
不同的钢筋混凝土结构，在选择单元类型时需要根据实际情况进行选择。
3. 网格密度
网格密度是指在分析过程中将钢筋混凝土模型离散化时所采用的网格
大小。
网格密度越高，分析结果越精确，但计算时间也会相应增长。
在确定网格密度时需要权衡精确性和计算时间。
4. 荷载与边界条件
在进行分析时需要设置结构的荷载、边界条件等参数。
这些参数直接
影响到计算结果的准确性。
在设置荷载和边界条件时要考虑实际情况，确保计算结果的合理性。
总之，设置合适的参数是获得准确的钢筋混凝土结构分析结果的关键。
在进行分析时要结合实际情况，根据需要进行适当调整，确保计算结
果的准确性和可靠性。
基于ABAQUS的混凝土材料非线性本构模型的研究
457.2mm
钢筋
均布线荷载 17.5kN/mm 229mm
152mm t1 t2
从而导致迭代时的不收敛以致分析失败。 而这些问题都有待于 我们在今后更加深入的研究和学习。
t1=38.1mm t2=31mm 图 1 钢筋混凝土单向板 混凝土材料参数 （GPa ） E 29 ε 0.1 v 0.18 / kg · m- 3 ） ρ（ 2400 ） σc（ 0 MPa 24.1 σu/MPa 2.45
基于 ABAQUS 的混凝土材料非线性本构模型的研究
关 虓， 冯仲奇
（西安建筑科技大学， 理学院， 陕西 西安 710055 ）
摘 要：主要讨论了利用大型通用非线性有限元分析软件 ABAQUS 对 钢筋混凝土构件进行非线性有限元分析，重点对 ABAQUS 提供的混凝 土本构模型、 破坏准则、 钢筋的本构关系以及如何在 ABAQUS 中处理钢 筋与混凝土的粘结滑移效应进行深入研究， 并针对混凝土受拉区的非线 将 性行为提出了固定弥散裂缝模型进行模拟。最后通过一个算例分析， 实验结果与数值模拟结果进行分析比较，证明了运用 ABAQUS 对钢筋 混凝土构件进行分析有较好的精度。 关键词： ABAQUS； 混凝土材料； 非线性； 本构模型 中图分类号： TU528.01 文章编号： 1007- 7359(2010)01- 0089- 02 文献标识码： A
其中， c0 为参数，可以通过混凝土单轴和双轴受压行为定
c0=9
ε bc
3 rbcε 姨 3 - a0 + a0- 姨 2 rbcε rbcε a0- 姨 3 + c
c
c
c
c
-4a0
c
c
c c 2姨3
c
基于ABAQUS梁单元的钢筋混凝土框架结构数值模拟共3篇
基于ABAQUS梁单元的钢筋混凝土框架结构数值模拟共3篇基于ABAQUS梁单元的钢筋混凝土框架结构数值模拟1钢筋混凝土框架结构是一种常见的建筑结构形式，具有较高的承载能力和良好的抗震性能。
数值模拟是研究结构力学性能和优化设计的重要手段之一。
本文将介绍基于ABAQUS梁单元的钢筋混凝土框架结构数值模拟方法和实现步骤。
ABAQUS是一种广泛应用于结构力学和工程分析的有限元分析软件，可以模拟不同类型的结构，包括钢筋混凝土框架结构。
在ABAQUS中，钢筋混凝土框架结构使用的是梁单元（B31）和三角形单元（C3D4）。
本文将重点介绍梁单元的应用。
首先，建立模型，包括结构几何形状、截面形状、材料特性等信息。
在ABAQUS中，可以通过建立草图、绘制型材、定义截面属性等方式来创建模型。
需要注意的是，建立的模型必须符合实际结构的几何形状和尺寸要求。
其次，定义材料特性，包括钢筋混凝土的弹性模量、泊松比、屈服强度、极限强度、裂缝韧度等参数。
这些参数对于结构的强度、刚度、稳定性等性能都有很大的影响，需要根据实际情况进行精确的定义。
然后，给结构施加荷载，包括静态荷载、动态荷载、地震荷载等。
在ABAQUS中，可以通过绘制荷载分布或者定义节点荷载、边界约束等方式来施加荷载。
需要注意的是，荷载的大小和方向必须符合实际情况。
最后，进行数值模拟，求解结构的应力、应变、变形等参数。
在ABAQUS中，可以通过指定分析步数、时间步长、求解器、后处理选项等方式来进行数值模拟。
需要注意的是，模拟结果的准确性和可靠性与模型的精度、材料参数和荷载条件等因素密切相关，需要认真评估和验证。
总的来说，基于ABAQUS梁单元的钢筋混凝土框架结构数值模拟是一项复杂的工程计算工作，需要具备专业的结构力学知识和ABAQUS软件的使用技能。
在模拟过程中，需要考虑许多因素，如模型准确性、材料参数、荷载条件、求解器选项等。
因此，需要认真分析和解决各种问题，确保模拟结果的准确性和可靠性，为结构设计和施工提供科学依据。
ABQUS中的三种混凝土本构模型
.ABQUS中的三种混凝土本构模型ABAQUS 用连续介质的方法建立描述混凝土模型不采用宏观离散裂纹的方法描述裂纹的水平的在每一个积分点上单独计算其中。
低压力混凝土的本构关系包括：Concrete Smeared cracking model (ABAQUS/Standard)Concrete Brittle cracking model (ABAQUS/Explicit)Concrete Damage plasticity model高压力混凝土的本构关系：Cap model1、ABAQUS/Standard中的弥散裂缝模型Concrete Smeared cracking model (ABAQUS/Standard)：——只能用于ABAQUS/Standard中裂纹是影响材料行为的最关键因素，它将导致开裂以及开裂后的材料的各向异性用于描述：单调应变、在材料中表现出拉伸裂纹或者压缩时破碎的行为在进行参数定义式的Keywords：*CONCRETE*TENSION STIFFENING*SHEAR RETENTION*FAILURE RATIOS2、ABAQUS/Explicit中脆性破裂模型Concrete Brittle cracking model (ABAQUS/Explicit) ：适用于拉伸裂纹控制材料行为的应用或压缩失效不重要，此模型考虑了由于裂纹引起的材料各向异性性质，材料压缩的行为假定为线弹性，脆性断裂准则可以使得材料在拉伸应力过大时失效。
在进行参数定义式的Keywords*BRITTLE CRACKING,*BRITTLE FAILURE,*BRITTLE SHEAR3、塑性损伤模型Concrete Damage plasticity model：适用于混凝土的各种荷载分析，单调应变，循环荷载，动力载荷，包含拉伸开裂(cracking)和压缩破碎(crushing)，此模型可以模拟硬度退化机制以及反向加载刚度恢复的混凝土力学特性在进行参数定义式的Keywords：*CONCRETE DAMAGED PLASTICITY*CONCRETE TENSION STIFFENING*CONCRETE COMPRESSION HARDENING*CONCRETE TENSION DAMAGE*CONCRETE COMPRESSION DAMAGE1 / 1'.。
ABAQUS显式分析梁单元的混凝土、钢筋本构模型共3篇
ABAQUS显式分析梁单元的混凝土、钢筋本构模型共3篇ABAQUS显式分析梁单元的混凝土、钢筋本构模型1在ABAQUS中，梁单元是一种经常用于模拟混凝土和钢筋梁的元素。
它使用线性或非线性混凝土本构模型和钢筋本构模型来描述材料的行为，并考虑梁单元在三个方向上的应力和应变。
混凝土本构模型:ABAQUS提供了多个混凝土本构模型，它们可以用于描述混凝土的本构行为。
其中一个常用的模型是Mander本构模型，它考虑了混凝土的三个不同阶段的行为：1. 压缩阶段: 混凝土在受到压缩时会逐渐变硬，所以Mander模型使用一个非线性的应力-应变关系来描述混凝土的压缩行为。
该模型使用三个参数来描述混凝土在不同应变范围内的硬化行为。
2. 弯曲-拉伸阶段: 当混凝土受到弯曲或拉伸时，会发生一些微小的裂缝，导致其变得更容易受到破坏。
因此，Mander模型采用一个渐进应力-应变关系来描述混凝土的弯曲和拉伸行为。
该模型也使用三个参数来描述不同应变范围内的弯曲和拉伸行为。
3. 破坏阶段: 当混凝土受到极大应力时，会发生破坏。
为了模拟破坏行为，Mander模型使用两个参数来描述混凝土的弹性模量和极限应变。
当混凝土受到超过极限应变的应变时，该模型将输出一个非常大的应力值，这意味着梁单元已经破坏。
钢筋本构模型:ABAQUS也提供了多个钢筋本构模型。
其中一个常用的模型是多屈服弹塑性模型，它考虑了钢筋的应力-应变关系的多个拐点：1. 弹性阶段: 在应力小于屈服强度时，钢筋的行为是弹性的。
因此，多屈服弹塑性模型使用一个线性应力-应变关系来描述弹性阶段的行为。
2. 屈服阶段: 当钢筋的应力达到屈服强度时，它的行为将开始变得非线性。
因此，多屈服弹塑性模型使用一个拐点来描述屈服后的应力-应变关系。
该模型使用一组参数来描述每个拐点的应力和应变差。
3. 再次弹性阶段: 当钢筋的应变超过屈服点后，它的应变-应力关系将再次变得线性。
多屈服弹塑性模型也考虑了这个阶段的行为。
混凝土的几种本构模型
武汉理工大学弹塑性理论学习论文混凝土的本构模型研究学院（系）：土木工程与建筑学院专业班级：土木研1005班学生姓名：梁庆学指导教师：张光辉混凝土的本构模型研究梁庆学（武汉理工大学土木工程与建筑学院，武汉 430070）摘要：在《弹塑性理论》这门课程中，我们学习了应力理论、应变理论和本构关系的一些相关知识。
虽然只有短短的几个月的时间，但这对于引导我们自学和探讨是非常有帮助的。
我在学完本构关系相关知识后，自己阅读相关的专业书籍和查阅了相关的科技论文文献,对混凝土的本构模型有了一些初步的了解，也对其产生了比较浓厚的兴趣，本文主要依据弹塑性理论对混凝土的本构模型最了一些简单的阐述总结。
关键词：本构关系；本构模型；线弹性模型；非线弹性模型；塑性理论模型The Study of ConstitutiveModel of ConcreteQing-xue Liang(Civil Engineering and Architecture School Wuhan University of Technology, Wuhan 430070)Abstract: In the course of “elastic-plastic theory”, we have learned some knowledge about stress theory, strain theory and constitutive relation. Although only several months’study, it’s helpful to lead us self-study and discussion. After learning the knowledge about constitutive relation, I have read some relevant professional books and reviewed some scientific papers related constitutive relation. I have got some preliminary understanding about the constitutive model of concrete, and I’m interested to it too. In this paper, I give some simple summary to the constitutive model of concrete based on the elastic-plastic theory.Key words:Constitutive relation; Constitutive model; Linear-elastic model; Non-linear-elastic model; Plastic theory model1 绪论混凝土是一种在工程结构中应用及其广泛的材料，在相当长时间内是依靠经验公式进行设计与分析的, 近几十年来, 随着电子计算机的普及,混凝土非线性有限元分析得到了很大的发展, 有关混凝土的本构关系得到了广泛而深入的研究。
ABAQUS建模教程
ABAQUS结构工程实例建模教程第1章建模方法介绍本章通过一框架剪力墙结构，详细介绍了三种建模方法，并在ABAQUS中对模型进行了模态分析。
注意：这里建立的模型只包括混凝土一种材料，对于钢筋的建立，将在后续章节中详细介绍。
【例题1.1】模型为九层混凝土框-剪结构，如图1. 1和图1. 2所示。
基本数据如下：➢柱：500mm ×500mm➢梁：250mm×500mm➢混凝土：C30➢剪力墙：250mm➢层高: 一层4500mm，二~九层3600mm图1. 1 结构尺寸图1. 2分析模型1.1 【方法一】直接在ABAQUS中建立模型单位制：N、m、kg、s1.1.1 Part模块—建立首层和标准层进入Part模块—Create Part，如图1. 3，Part-1为首层平面，如图1. 4；标准层与首层只是层高不同，而平面布置完全一样，所以可以在左侧模型树Parts—Part-1右击，点击Copy，如图1. 5，进入Part Copy窗口，如图1. 6，命名为Part-2。
图1. 3图1. 4图1. 5图1. 6在菜单栏中点击Tool—Datum，进入Create Datum窗口，如图1. 7所示，Type 选择Point，Method选择Offset from point。
选择有柱的点，在左下角（如图1. 8）Offset（X，Y，Z）中输入（0,0，-4.5），完成之后如图1. 9。
图1. 7图1. 8图1. 9在环境栏中选择，如图1. 10，弹出Create Wire Feature 窗口，如图1. 11，Add method选择Disjoint wires，通过Add，连接柱子的两个端点，完成之后如图1. 12。
同理，可以生成标准层Part-2的柱子。
图1. 10图1. 11图1. 12建立首层剪力墙Part-3，Part—Create Part（如图1. 13），点击，在左下角starting point输入（0,0），end point输入（0,6），如图1. 14，点击Done，弹出Edit Base Extrusion窗口，如图1. 15，在Depth中输入4.5，完成之后如图1. 16。
混凝土本构模型
混凝土本构模型混凝土是一种常用的结构材料，具有很强的抗压强度和耐久性。
为了有效地分析和设计混凝土结构，人们提出了混凝土本构模型，用于描述混凝土材料的力学性能。
本文将介绍混凝土本构模型的基本概念、常用模型以及模型选择的几个关键因素。
1. 混凝土本构模型的基本概念混凝土的本构模型是一种数学模型，用于描述混凝土在力学加载下的应力-应变关系。
它基于实验数据和理论分析，通过一组公式或曲线来模拟混凝土的弹性和塑性行为。
常见的本构模型包括弹性模型、线性本构模型、非线性本构模型等。
2. 常用的2.1 弹性模型弹性模型是最简单的混凝土本构模型之一，它假设混凝土在加载过程中具有线性弹性行为。
根据胡克定律，混凝土的应力和应变之间存在着线性关系。
在小应变范围内，弹性模型能够较好地描述混凝土的力学性能，但它无法考虑材料的非线性行为。
2.2 线性本构模型线性本构模型相比于弹性模型更为复杂，它考虑了混凝土的非线性行为。
其中最为常用的是双曲线模型和抛物线模型。
双曲线模型通过将应力-应变曲线分为上升段和下降段，分别使用线性和非线性公式描述，能够较好地模拟混凝土在受压和受拉状态下的应力-应变关系。
抛物线模型则是通过二次方程来拟合混凝土的应力-应变曲线，在一定程度上考虑了混凝土的非线性特性。
2.3 非线性本构模型非线性本构模型较为复杂，但能够更准确地描述混凝土在大变形情况下的力学性能。
常见的非线性本构模型包括双参数本构模型、Drucker-Prager本构模型、Mohr-Coulomb本构模型等。
这些模型能够考虑混凝土在各向异性和多轴加载条件下的非线性行为，适用于复杂的结构分析和设计。
3. 模型选择的关键因素选择适合的混凝土本构模型是结构分析和设计的关键一步，需要考虑以下因素：3.1 加载条件不同的加载条件会对混凝土的力学性能产生不同的影响，例如受压、受拉、剪切等。
在选择本构模型时，需要根据具体的加载条件确定模型的参数和表达形式。
3.2 大应变效应部分混凝土结构在强震等极端加载条件下可能发生较大应变，此时需要考虑混凝土的非线性行为。
三种混凝土本构模型
ABAQUS中的三种混凝土本构模型2010-05-12 22:19:14| 分类：ABAQUS | 标签：|字号大中小订阅资料来自SIMWE论坛shanhuimin923，特表示感谢！ABAQUS 用连续介质的方法建立描述混凝土模型不采用宏观离散裂纹的方法描述裂纹的水平的在每一个积分点上单独计算其中。
低压力混凝土的本构关系包括：Concrete Smeared cracking model (ABAQUS/Standard)Concrete Brittle cracking model (ABAQUS/Explicit)Concrete Damage plasticity model高压力混凝土的本构关系：Cap model1、ABAQUS/Standard中的弥散裂缝模型Concrete Smeared cracking model(ABAQUS/Standard)：——只能用于ABAQUS/Standard中裂纹是影响材料行为的最关键因素，它将导致开裂以及开裂后的材料的各向异性用于描述：单调应变、在材料中表现出拉伸裂纹或者压缩时破碎的行为在进行参数定义式的Keywords：*CONCRETE*TENSION STIFFENING*SHEAR RETENTION*FAILURE RATIOS2、ABAQUS/Explicit中脆性破裂模型Concrete Brittle cracking model (ABAQUS/Explicit) ：适用于拉伸裂纹控制材料行为的应用或压缩失效不重要，此模型考虑了由于裂纹引起的材料各向异性性质，材料压缩的行为假定为线弹性，脆性断裂准则可以使得材料在拉伸应力过大时失效。
在进行参数定义式的Keywords*BRITTLE CRACKING,*BRITTLE FAILURE,*BRITTLE SHEAR3、塑性损伤模型Concrete Damage plasticity model：适用于混凝土的各种荷载分析，单调应变，循环荷载，动力载荷，包含拉伸开裂(cracking)和压缩破碎(crushing)，此模型可以模拟硬度退化机制以及反向加载刚度恢复的混凝土力学特性在进行参数定义式的Keywords：*CONCRETE DAMAGED PLASTICITY*CONCRETE TENSION STIFFENING*CONCRETE COMPRESSION HARDENING*CONCRETE TENSION DAMAGE*CONCRETE COMPRESSION DAMAGE。
4.1ABAQUS中的混凝土本构模型(5页)
14 ABAQUS中的混凝土本构模型4.1 概述A wide variety of materials is encountered in stress analysis problems, and for any one of these materials a range of constitutive models is available to describe the material's behavior. For example, a component made from a standard structural steel can be modeled as an isotropic, linear elastic, material with no temperature dependence. This simple model would probably suffice for routine design, so long as the component is not in any critical situation. However, if the component might be subjected to a severe overload, it is important to determine how it might deform under that load and if it has sufficient ductility to withstand the overload without catastrophic failure. The first of these questions might be answered by modeling the material as a rate-independent elastic, perfectly plastic material, or—if the ultimate stress in a tension test of a specimen of the material is very much above the initial yield stress—isotropic work hardening might be included in the plasticity model. A nonlinear analysis (with or without consideration of geometric nonlinearity, depending on whether the analyst judges that the structure might buckle or undergo large geometry changes during the event) is then done to determine the response. But the severe overload might be applied suddenly, thus causing rapid straining of the material. In such circumstances the inelastic response of metals usually exhibits rate dependence: the flow stress increases as the strain rate increases. A ―viscoplastic‖ (rate-dependent) material model might, therefore, be required. (Arguing that it is conservative to ignore this effect because it is a strengthening effect is not necessarily acceptable—the strengthening of one part of a structure might cause load to be shed to another part, which proves to be weaker in the event.) So far the analyst can manage with relatively simple (but nonlinear) constitutive models. But if the failure is associated with localization—tearing of a sheet of material or plastic buckling—a more sophisticated material model might be required because such localizations depend on details of the constitutive behavior that are usually ignored because of their complexity (see, for example, Needleman, 1977). Or if the concern is not gross overload, but gradual failure of the component because of creep at high temperature or because of low-cycle fatigue, or perhaps a combination of these effects, then the response of the material during several cycles of loading, in each of which a small amount of inelastic deformation might occur, must be predicted: a circumstance in which we need to model much more of the detail of the material's response.So far the discussion has considered a conventional structural material. We can broadly classify the materials of interest as those that exhibit almost purely elastic response, possibly with some energy dissipation during rapid loading by viscoelastic response (the elastomers, such as rubber or solid propellant); materials that yield andexhibit considerable ductility beyond yield (such as mild steel and other commonly used metals, ice at low strain rates, and clay); materials that flow by rearrangement of particles that interact generally through some dominantly frictional mechanism (such as sand); and brittle materials (rocks, concrete, ceramics). The constitutive library provided in Abaqus contains a range of linear and nonlinear material models for all of these categories of materials. In general the library has been developed to provide those models that are most usually required for practical applications. There are several distinct models in the library; and for the more commonly encountered materials (metals, in particular), several ways of modeling the material are provided, each suitable to a particular type of analysis application. But the library is far from comprehensive: the range of physical material behavior is far too broad for this ever to be possible. The analyst must review the material definitions provided in Abaqus in the context of each particular application. If there is no model in the library that is useful for a particular case, Abaqus/Standard contains a user subroutine—UMAT—and, similarly, Abaqus/Explicit contains a user subroutine—VUMAT. In these routines the user can code a material model (or call other routines that perform that task). This ―user subroutine‖ capability is a powerful resource for the sophisticated analyst who is able to cope with the demands of programming a complex material model.Theoretical aspects of the material models that are provided in Abaqus are described in this chapter, which is intended as a definition of the details of the material models that are provided: it also provides useful guidance to analysts who might have to code their own models in UMAT or VUMAT.From a numerical viewpoint the implementation of a constitutive model involves the integration of the state of the material at an integration point over a time increment during a nonlinear analysis. (The implementation of constitutive models in Abaqus assumes that the material behavior is entirely defined by local effects, so each spatial integration point can be treated independently.) Since Abaqus/Standard is most commonly used with implicit time integration, the implementation must also provide an accurate ―material stiffness matrix‖ for use in fo rming the Jacobian of the nonlinear equilibrium equations; this is not necessary for Abaqus/Explicit.The mechanical constitutive models that are provided in Abaqus often consider elastic and inelastic response. The inelastic response is most commonly modeled with plasticity models. Several plasticity models are described in this chapter. Some of the constitutive models in Abaqus also use damage mechanics concepts, the distinction being that in plasticity theory the elasticity is not affected by the inelastic deformation (the Young's modulus of a metal specimen is not changed by loading it beyond yield, until the specimen is very close to failure), while damage models include the degradation of the elasticity caused by severe loading (such as the loss of elastic stiffness suffered by a concrete specimen after it has been subjected to large uniaxial compressive loading).2In the inelastic response models that are provided in Abaqus, the elastic and inelastic responses are distinguished by separating the deformation into recoverable (elastic) and nonrecoverable (inelastic) parts. This separation is based on the assumption that there is an additive relationship between strain rates:where is the total strain rate, is the rate of change of the elastic strain, and isthe rate of change of inelastic strain.A more general assumption is that the total deformation, , is made up of inelasticdeformation followed by purely elastic deformation (with the rigid body rotation added in at any stage in the process):In ―The additive strain rate decomposition,‖ Section 1.4.4, the circumstances are discussed under which Equation 4.1.1–1is a legitimate approximation to Equation 4.1.1–2. We conclude that, if1.the total strain rate measure used in Equation 4.1.1–1is the rate ofdeformation:where is the velocity and is the current spatial position of a material point;and2.the elastic strains are small,then the approximation is consistent. Abaqus uses the rate of deformation as the strain rate measure in finite-strain problems for this reason. (The distinction between different strain measures matters only when the strains are not negligible compared to unity; that is, in finite-strain problems.) The elastic strains always remain small for many materials of practical interest; for example, the yield stress of a metal is typically three orders of magnitude smaller than its elastic modulus, implying elasticstrains of order . However, some materials (polymers, for example) can undergo large elastic straining and also flow inelastically, in which case the additive strain rate decomposition is no longer a consistent approximation.Various elastic response models are provided in Abaqus. The simplest of these is linear elasticity:where is a matrix that may depend on temperature but does not depend on the deformation (except when such dependency is introduced in damage models). This elasticity model is intended to be used for small-strain problems or to model the elasticity in an elastic-plastic model in which the elastic strains are always small.An extension of the elastic type of behavior is the hypoelastic model:where now may depend on the deformation. In this case the elasticity may be nonlinear, but the implementation in Abaqus still assumes that the elastic strains will always be small. In porous and granular media, the elastic properties are strongly dependent on the volume strain; porous elastic behavior is described in ―Porous elasticity,‖ Section 4.4.1.The most general type of nonlinear elastic behavior is the hyperelastic model, in which we assume that there is a strain energy density potential—U—from which the stresses are defined (to within a hydrostatic stress value if the material is fully incompressible) bywhere and are any work conjugate stress and strain measures. This form of elasticity model is generally used to model elastomers: materials whose long-term response to large deformations is fully recoverable (elastic). The hyperelasticity modeling provided in Abaqus is described in ―Large-strain elasticity,‖ Section 4.6. The hyperelasticity models cannot be used with the plastic deformation models in the program, but can be combined with viscoelastic behavior, as described in ―Finite-strain viscoelasticity,‖ Section 4.8.2.The plasticity models offered in Abaqus are discussed in general terms in ―Plasticity overview,‖ Section 4.2. Both rate-independent and rate-dependent models, with and without yield surfaces, are offered. Models are included in the program that are intended for applications to metals (―Metal plasticity,‖ Section 4.3) as well as some nonmetallic materials such as soils, polymers, and crushable foams (―Pl asticity for non-metals,‖ Section 4.4). The jointed material model (―Constitutive model for jointed materials,‖ Section 4.5.4) and the concrete model (―An inelastic constitutive model for concrete,‖ Section 4.5.1) also include plasticity modeling.The constitutive routines in Abaqus exist in a library that can be accessed by any of the solid or structural elements. This access is made independently at each ―constitutive calculation point.‖ These points are the numerical integration points in the elements. Thus, the constitutive routines are concerned only with a single calculation point. The element provides an estimate of the kinematic solution to the problem at the point under consideration. These kinematic data are passed to the constitutive routines as the deformation gradient——or, more typically, as the strain and rotation increments—and . The constitutive routines obtain the state atthe point under consideration at the start of the increment from the ―material point data base.‖ The state variables include the stress and any state variables used in the constitutive models—plastic strains, for example. The constitutive routines also look up the constitutive definition. Their function then is to update the state to the end of the increment and, if the procedure uses implicit time integration and if Newton's method is being used to solve the equations, to define the material contribution to theJacobian matrix, . For material models that are defined in rate form and, therefore, require integration (such as incremental plasticity models), this Jacobian contribution depends on the model and also on the integration method used for the model. Its derivation is, therefore, discussed in some detail in the sections that define such models.Reference―Material library: overview,‖ Section 18.1.1 of the Abaqus Analysis User's Manual。
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ABAQUS用连续介质的方法建立描述混凝土模型不采用宏观离散裂纹的方法描述裂纹的水平的在每一个积分点上单独计算其中。
低压力混凝土的本构关系包括：
Con crete Smeared cracki ng model (ABAQUS/Sta ndard)
Concrete Brittle cracki ng model (ABAQUS/Explicit)
Con crete Damage plasticity model
高压力混凝土的本构关系：
Cap model
1、ABAQUS/Standard 中的弥散裂缝模型Concrete Smeared cracking model (ABAQUS/Standard):
只能用于ABAQUS/Standard 中
裂纹是影响材料行为的最关键因素，它将导致开裂以及开裂后的材料的各向异性
用于描述：单调应变、在材料中表现出拉伸裂纹或者压缩时破碎的行为
在进行参数定义式的Keywords:
*CONCRETE
*TENSION STIFFENING
*SHEAR RETENTION
*FAILURE RATIOS
2、ABAQUS/Explicit 中脆性破裂模型Concrete Brittle cracking model (ABAQUS/Explicit): 适用于拉伸裂纹控制材料行为的应用或压缩失效不重要，此模型考虑了由于裂纹引起的材料
各向异性性质，材料压缩的行为假定为线弹性，脆性断裂准则可以使得材料在拉伸应力过大
时失效。
在进行参数定义式的Keywords
*BRITTLE CRACKING,
*BRITTLE FAILURE,
*BRITTLE SHEAR
3、塑性损伤模型Concrete Damage plasticity model :
适用于混凝土的各种荷载分析，单调应变，循环荷载，动力载荷，包含拉伸开裂(cracking)和压缩破碎(crushing)，此模型可以模拟硬度退化机制以及反向加载刚度恢复的混凝土力学特性
在进行参数定义式的Keywords:
*CONCRETE DAMAGED PLASTICITY
*CONCRETE TENSION STIFFENING
*CONCRETE COMPRESSION HARDENING
*CONCRETE TENSION DAMAGE
*CONCRETE COMPRESSION DAMAGE。