匀质化数值模型中砌体材料破坏准则的实验研究

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3.0 侯斌 2025-01-09 16 4 31.69MB 97 页 15积分

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摘要

目前，现有的针对砌体结构的模拟方法主要包括连续介质理论的有限单元法

和基于块体集合理论的离散单元法。但是，前者尚不能很好模拟砌体中裂缝发展的

过程及开裂后构件的性能，而后者面临在低应力水平时计算精度不高、结构分析耗

时较长等困难。因此，文章基于前两种方法，利用匀质化思想，选取具有相同组砌

特点的等效体积单元（Representative Volume Element， RVE）作为“连续材料”

建模。从砌体多尺度上对破坏准则进行研究，其破坏准则由材料尺度的物理特点，

即砂浆强度、块体强度和砌体组砌方式确定。

研究的主要内容与成果有：

（1）考虑三种砌筑方式、两种灰缝厚度，分别对砌体试件进行了抗压性能实

验。从砂浆灰缝厚度以及砌筑方式的改变来研究其对砌体抗压性能的敏感性影响。

实验结果表明，砌体的抗压强度随水平灰缝所占提价百分比的增大而减小。全顺式

砌筑的砌体（本文中的方式 2）抗压强度较低；在规范允许的砂浆灰缝厚度下限值

之上且砌筑条件相同时，灰缝厚度越大，抗压强度越低。

（2）在已获得的试件抗压强度的基础上，考虑 9种压剪应力状态的影响，通

过特别设计的夹具对砌体试件进行了压剪承载性能实验。根据实验结果将砌体材

料的破坏分为剪磨、压剪和斜压三种形式，获得了其在压剪状态下的完整破坏曲线。

由实验结果知，压力的大小对砌体的压剪破坏影响显著，其破坏可分为剪摩、剪压

和斜压三种形式。在剪压和斜压破坏中，裂缝均会贯穿块体。

（3）基于砌体试件抗压强度以及压剪相关曲线，按照匀质化理论对所选取的

普通烧结砖砌体等效体积元（RVE）进行压剪相关曲线的回归，并对其进行 RVE

砌体压剪承载性能的定性分析。当 σy / f m<0.4 发生剪磨破坏，当 0.4<σy / f m<0.68

时发生剪压破坏，而当 σy / f m>0.68～1.0 时发生斜压破坏。

（4）综合考虑实验破坏曲线的形态和数值模拟对破坏面光滑性的要求，发现

Drucker-Prager 准则适用于描述砌体材料的压剪破坏，其参数可由实验结果进行标

定。将标定后的 Drucker-Prager 准则应用于等效体积单元模型，对砌体试件受压实

验和砌体墙片伪静力实验进行了数值模拟，模拟结果与实验结果符合程度较好。当

有限元模型中单元的大小与压剪试验试件大小接近，即满足 RVE 模型的条件时，

其计算结果更接近试验结果。不同砌筑方式的砌体，压剪破坏形态有差异，其对应

DP 破坏准则的参数不相同。在受压状态下，砌筑方式对破坏准则的影响比在压剪

状态下更明显。

关键词：砌体破坏准则等效体积单元 Drucker-Prager 准则数值模

拟

ABSTRACT

At present, the existing simulation method of masonry structure mainly includes

the theory of continuous medium finite element method and discrete element method

based on block set theory. However, the former has not yet been a good simulation of

masonry cracks after cracking the progress and performance of components, and the

latter is facing a low stress level accuracy which is not high, structural analysis taking

a long time and other difficulties. Therefore, the article based on the first two methods

and homogenized thought,it chooses a representative volume element which has the

same group of masonry features as "continuous material" modeling. To study the failure

criteria from masonry multitudes, which are by the physical characteristics of the

material dimension, namely the strength of mortar, masonry block body strength and

masonry way.

The main contents of the research are as follows:

（1）Consider three types of masonry, two kinds of mortar joint thickness,

respectively, masonry specimen are taking compressive performance experiment. The

sensitivity effect on the compressive properties of masonry is studied from mortar joint

thickness and the change of masonry.

（2）Taking into account the influences of the bricklaying, the depth of the mortar

bed, and the shear-compressing ratio is conducted through a special clamp. The failure

of the specimen is ranked based on the test results into 3 types, i. e., the shear-friction

failure, the shear-compression failure, and the diagonal compressive failure, and

integral failure curves for the specimen under combined shear and compression are

established.

（3）The failure criteria with existing masonry structures compare with

compression and shear curve based on the test to finally obtain the failure criterion of

complete RVE unit, and give the corresponding expressions.

（4）Considering the test results and the smoothness of the failure surface. The

Drucher-Prager criteria are suitable for describing the damage of masonry, and the

parameters in the criteria can be calibrated by the test results. The calibrated Drucher-

Prager criteria are used in RVE models, by which the compressive tests and pseudo-

static tests for masonry specimen are simulated. The simulated results are in good

agreement with the test results. The research procedure and findings can be sent back

in numerical analysis for masonry structures.

Key Word: masonry, shear-compression failure, representative volume

element （RVE ）, Drucker-Prager criteria, numerical

simulation

中文摘要

ABSTRACT

第一章绪论 ............................................................................................................ 1

1.1 引言 ................................................................................................................ 1

1.2 研究现状 ........................................................................................................ 2

1.2.1 经典强度理论与砌体破坏准则 ............................................................... 2

1.2.2 砌体数值分析研究现状 ........................................................................... 5

1.2.3 砌体的匀质化思想的提出 ....................................................................... 7

1.3 本文的主要研究内容 ..................................................................................... 8

第二章砌体试件抗压性能实验研究 .................................................................... 10

2.1 砌体抗压性能实验 ...................................................................................... 10

2.1.1 试件的设计与制作 ................................................................................ 10

2.1.2 实验装置及实验过程............................................................................. 12

2.2 砌体试件抗压性能实验结果 ....................................................................... 17

2.2.1 破坏形态 ................................................................................................ 17

2.2.2 实验结果评定 ........................................................................................ 19

2.2.3 试件抗压性能影响因素分析 ................................................................. 20

2.3 小结 .............................................................................................................. 23

第三章砌体压剪承载性能实验研究 .................................................................... 24

3.1 砌体压剪承载性能实验 .............................................................................. 24

3.1.1 试件的设计与制作 ................................................................................ 24

3.1.2 实验装置 ................................................................................................ 24

3.1.3 实验过程 ................................................................................................ 25

3.2 砌体压剪承载性能实验结果及分析 ........................................................... 26

3.2.1 破坏形态 ................................................................................................ 26

3.2.2 实验结果评定 ........................................................................................ 29

3.3 小结 ............................................................................................................. 32

第四章砌体 RVE 压剪强度分析 .......................................................................... 33

4.1 实验数据与已有压剪相关曲线的回归方式的比较 ..................................... 33

4.1.1 无帽处理的回归方式............................................................................. 33

4.1.2 加帽处理的回归方式............................................................................ 36

4.2 砌体 RVE 的压剪相关曲线的回归 ............................................................. 40

4.2.1 摩擦系数 μ值和峰值点位置的选取 ..................................................... 41

4.2.2 砌体 RVE 的压剪相关曲线的回归的表达式 ........................................ 42

4.3 砌体 RVE 压剪承载性能的分析 ................................................................. 46

4.4 小结 .............................................................................................................. 46

第五章砌体抗压性能实验与砌体匀质化模型数值分析的对比验证 .................. 48

5.1 砌体抗压性能实验 ....................................................................................... 48

5.1.1 砌体抗压性能实验研究方案 ................................................................. 48

5.1.2 砌体抗压性能实验结果 ........................................................................ 49

5.2 砌体有限元模型的建立 .............................................................................. 50

5.2.1 单元类型 ............................................................................................... 51

5.2.2 屈服准则及材料本构关系 .................................................................... 51

5.2.3 模型建立与网格划分............................................................................ 52

5.2.4 加载及求解设置 ................................................................................... 53

5.2.5 有限元分析模型的验证 ........................................................................ 54

5.3 数值模拟与实验结果的对比分析 ............................................................... 56

5.3.1 不同组砌方式标定的 DP 准则参数对数值模拟结果的影响 ............... 56

5.3.2 不同网格划分对数值模拟结果的影响 ................................................. 57

5.4 影响砌体抗压性能数值模拟结果的 DP 准则参数分析 ............................. 60

5.4.1DP 准则参数的影响 ............................................................................... 60

5.4.2DP 准则参数的影响原因分析 ................................................................ 61

5.5 小结 .............................................................................................................. 62

第六章无筋砌体墙伪静力实验数值模拟 ............................................................ 64

6.1 无筋砌体墙伪静力实验 ............................................................................... 64

6.1.1 试件设计与制作 .................................................................................... 64

6.1.2 测点布置及量测内容............................................................................. 66

6.1.3 加载制度 ................................................................................................ 67

6.1.4 实验结果 ................................................................................................ 69

6.2 不同材料间 DP 准则参数的换算 ................................................................. 70

6.2.1 内摩擦角的换算 .................................................................................... 71

6.2.2 粘聚力的换算 ........................................................................................ 71

6.2.3 膨胀角的换算 ........................................................................................ 72

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