考虑温度变化与水浸泡作用的混凝土与岩石疲劳破坏的非线性力学分析

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摘要

本文主要对受雨水浸泡、循环荷载作用的混凝土、含裂纹体岩石及高温后岩

石的疲劳变形和破坏机理进行了试验研究，探讨了水浸泡、疲劳荷载作用对混凝

土力学性能的影响，分析了含裂纹体岩石材料的破坏机理，研究了含裂纹体岩石

材料的高频疲劳特性，建立了水浸泡混凝土损伤本构模型以及高温条件下岩石疲

劳破坏的准则和模型。

在实际工程中，许多混凝土结构经常在水环境下工作，混凝土中含有大量的

孔隙，包括混凝土成型时残留下来的气泡，水泥石中的毛细管孔腔和凝胶孔，以

及水泥石和集料接触处的孔穴等。在水压力的作用下，水将渗透到混凝土的孔隙

和裂缝中。受各种荷载的影响，混凝土中的孔隙水会对孔壁产生水压力，进而影

响混凝土的力学性能。

在实际工程领域，周期载荷作用下混凝土和岩石的疲劳损伤特性与工程的长

期稳定性密切相关。由于受到往复行驶车辆的循环荷载的作用，高速铁路和公路

桥梁的柱墩下方混凝土和岩体的破坏具有突发性，因此，有必要对混凝土和岩石

的疲劳破坏机理及疲劳损伤等问题进行深入研究。因此，本文主要就以下四个方

面的内容进行了研究：

(1) 多孔多相的饱和混凝土中，孔隙自由水对混凝土的力学特性有显著的影

响。本文基于损伤力学基本原理建立了单轴压缩条件下水饱和混凝土的弹塑性损

伤本构模型，并结合太沙基“有效应力原理”，认为材料的损伤是由本体有效应

力和结构有效应力引起的，根据应力平衡条件得出了两种有效应力下的应力关系

方程，并在此基础上建立了水饱和混凝土的单轴压缩损伤演化方程。

(2) 对圆柱形混凝土试件进行了高频疲劳等幅恒加载试验及变幅步进试验。对

试件的高频疲劳破坏机理进行了分析，建立了混凝土的轴向压缩非线性疲劳损伤

累积模型。然后对混凝土加速寿命试验结果进行了可靠性统计分析，建立考虑失

效概率

的

NSP 

疲劳方程。

(3) 以高强度白水泥为模拟材料，对含裂纹体岩石进行了单轴压缩试验以及高

频疲劳单轴压缩试验研究，推导出单轴压缩条件下试件应力强度因子的解析表达

式，分析了裂纹表面摩擦系数对试件应力强度因子的影响，并得到了含裂纹体岩

石材料的 S-lgN 曲线和考虑裂纹相互作用的疲劳方程。

(4) 对经历不同高温后花岗岩的力学性能进行试验研究，研究了花岗岩的峰值

应力、峰值应变、弹性模量、应力-应变曲线等随温度的变化规律，并通过回归分

析，得到了相应的回归公式；并建立了高温后花岗岩高频疲劳损伤模型，分析了

摘要

高温后花岗岩在高频疲劳荷载作用下的损伤发展和疲劳裂纹扩展规律，建立了高

温后花岗岩的损伤演化方程；且通过对经历不同高温后花岗岩进行高频疲劳试验，

研究了高温作用对花岗岩高频疲劳寿命的影响。经高频疲劳试验数据分析，所建

模型可以较好地反映岩石的疲劳损伤演化规律。

依据试验研究成果，总结受雨水浸泡和循环荷载作用的混凝土和不同温度影

响下岩石疲劳变形、弱化和破坏的规律。而这一问题的研究对解决目前正在建设

的高速铁路路基工程中的许多现实问题有重要指导作用。

关键词：混凝土岩石水浸泡高温高频疲劳疲劳损伤

ABSTRACT

The regularity and mechanism of the concrete under the influence of the rain

soaked and cycle loading and deformation, destruction and fatigue mechanism of rock

containing crack body and rock after different temperature are studied.The influence of

temperature change and water saturate on mechanical properties of concrete was

discussed. The destruction mechanism of rock material containing crack body was

analyzed. The high-frequency fatigue properties of rock material containing crack body

were studied. The damage constitutive model of water-saturated concrete under uniaxial

compression and fatigue damage norms and model of rock after high temperature were

established.

In practical engineering, many concrete structure often are applied in water

environment, a lot of pores are produced, including the remnant bubble in process of

concrete molding, capillary in cement and gel hole and hole between cement and

aggregate etc. Because of the action of water pressure, the porosity and concrete cracks

are permeated by water. Affected by various loads, water pressure of hole wall are

produced by the pore water in concrete, which further influence the mechanical property

of concrete.

In practical engineering field, periodic load of fatigue damage characteristics of

concrete and rock is closely related to the long-term stability. Due to the change of

temperature and reciprocating vehicles cycle load and the sudden destruction of

concrete and rock below high-speed railway and highway bridge pier column, it is

necessary to study mechanism of fatigue damage of concrete and rock coupling the

effect of temperature. Therefore, this article mainly studys from the following four

aspects:

(1) In multi-phase porous saturated concrete, pore water in the saturated concrete

has the remarkable influence on the mechanical property of concrete. Based on the basic

principles of damage mechanics, the elasto-plastic damage constitutive model of

water-saturated concrete under uniaxial compression is established. Combined with the

Terzaghi’s effective stress principle, the effective stresses of the body and structure lead

to the damage of material. According to the stress equilibrium condition, the two kinds

of effective stress relationship are attained. And on this basis, the damage evolution

equation of water-saturated concrete under uniaxial compression is established.

(2) Concrete cylinder specimens were tested under high frequency fatigue loads

ABSTRACT

with constant amplitude and increasing amplitude respectively in this paper. At first, the

failure mechanism of specimens under high frequency fatigue loads was analyzed and

the model for nonlinear fatigue damage cumulation under axial compressive loads was

established. Then statistical analysis concerning the reliability of the results for the

concrete in accelerated life test was done, and the fatigue equation about P—S—N

taking account of failure probability P’ was put forward.

(3) In this paper, white cement is adopted as the experimental material for

simulating rocks, Uniaxial loading tests and high-frequency fatigue tests of rock

specimens with Cracks were conducted, and the corresponding analytical expression of

stress intensity factor (SIF) was derived. The influence of surface friction coefficient of

crack on the stress intensity factor of the specimens was analyzed. Based on the

consideration of the interaction of the cracks, the S-lgN curves and the fatigue equation

for the rock specimens are obtained.

(4) The experimental studies on the mechanical properties of granite after different

temperature were conducted. The regularity of granite peak stress, peak strain, elastic

modulus, stress-strain curve with temperature variation was discussed. And, by

regression analysis, the corresponding regression formulas were obtained. The high

frequency fatigue damage model of granite after the high temperature was established.

Damage development and deformation of granite after high temperature under high

frequency fatigue load were analyzed. Damage evolution of granite after high

temperature was established. And through the high frequency fatigue test of granite after

high temperature, the regularity and mechanism of high frequency fatigue life of the

granite affected by high temperature was studied, and the damage model was verified.

According to the test results, the regularity and mechanism of the concrete under

the influence of the rain soaked and cycle loading and deformation, destruction and

fatigue of rock after different temperature are summarized. This research has many

important guiding roles to solve the high-speed railway subgrade engineering problems

in process of construction.

Key Words: concrete, rock, water-saturated, high temperature,

high frequency fatigue, fatigue damage

中文摘要

ABSTRACT

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

§1.1 研究背景 ................................................... 1

§1.2 研究意义 ................................................... 1

§1.3 水浸泡混凝土力学性能研究概况 ................................ 1

§1.3.1 水浸泡混凝土中的孔隙水压力 ............................ 1

§1.3.2 孔隙水压对混凝土抗压强度影响 .......................... 2

§1.3.3 混凝土损伤本构模型 .................................... 2

§1.4 混凝土疲劳性能研究概况 ...................................... 7

§1.4.1 疲劳的基本概念 ........................................ 7

§1.4.2 混凝土疲劳试验研究 ................................... 10

§1.5 岩石断裂力学性能研究概况 ................................... 11

§1.5.1 断裂力学概述 ......................................... 11

§1.5.2 应力强度因子理论、断裂韧性及断裂判据 ................. 12

§1.6 高温后岩石力学性能研究概况 ................................. 14

§1.7 岩石高频疲劳性能研究概况 ................................... 14

§1.8 研究内容 ................................................... 15

第二章水饱和混凝土单轴压缩弹塑性损伤本构模型 ....................... 17

§2.1 引言 ....................................................... 17

§2.2 试验设计 ................................................... 17

§2.3 机理分析 .................................................. 17

§2.4 损伤本构模型 .............................................. 19

§2.4.1 损伤本构模型 ......................................... 19

§2.4.2 损伤演化方程 ......................................... 20

§2.4.3 干燥和水饱和状态下应力-应变曲线及其比较 .............. 24

§2.5 本章小结 .................................................. 25

第三章混凝土高频疲劳试验研究 ....................................... 26

§3.1 引言 ....................................................... 26

§3.2 高频疲劳等幅恒加试验及变幅步进试验 ......................... 26

§3.2.1 静载试验 ............................................. 26

§3.2.2 高频疲劳试验加载装置简介 ............................. 26

§3.2.3 试验方案 ............................................. 27

§3.3 试验结果 ................................................... 27

§3.4 试验现象的分析比较 ......................................... 29

§3.4.1 疲劳破坏形态 ......................................... 29

§3.4.2 疲劳破坏裂纹扩展过程 ................................. 30

§3.5 混凝土高频疲劳试验的非线性累积损伤模型 ..................... 30

§3.6 混凝土高频和低频疲劳曲线的 Basquin 方程拟合 ................. 32

§3.7 混凝土的高频修正系数 ....................................... 33

§3.7.1 修正系数的定义 ....................................... 33

§3.7.2 高频疲劳试验结果修正 ................................. 33

§3.8 疲劳曲线与疲劳方程 ......................................... 34

§3.8.1 疲劳曲线 ............................................. 34

§3.8.2 考虑失效概率的

NSP 

疲劳方程 ...................... 35

§3.9 本章小结 ................................................... 36

第四章含裂纹体岩石材料的破坏机理及高频疲劳特性试验研究 .............. 37

§4.1 引言 ....................................................... 37

§4.2 岩石材料的制备 ............................................. 37

§4.3 抗压强度试验结果 ........................................... 38

§4.4 应力强度因子的解析表达式与数值分析 ......................... 42

§4.4.1 应力强度因子计算 ..................................... 42

§4.4.2 数值分析 ............................................. 44

§4.4.3 摩擦系数对裂纹应力强度因子的影响 ..................... 44

§4.5 高频疲劳试验 ............................................... 45

§4.5.1 单轴抗压试验及结果 ................................... 45

§4.5.2 试验设备及方案 ....................................... 46

§4.5.3 高频疲劳试验结果 ..................................... 47

§4.5.4 高频疲劳寿命方程 ..................................... 47

§4.6 本章小结 ................................................... 50

第五章高温后花岗岩单轴压缩力学性能及高频疲劳损伤试验研究 ........... 52

§5.1 引言 ....................................................... 52

§5.2 试验概况 ................................................... 52

§5.2.1 试件制作 ............................................. 52

§5.2.2 加热设备 ............................................. 52

§5.2.3 试验设备 ............................................. 52

§5.3 单轴压缩试验结果与分析 ..................................... 54

§5.3.1 机理分析 ............................................. 57

§5.3.2 应力-应变曲线随温度的变化规律 ........................ 58

§5.3.3 峰值应力随温度的变化规律 ............................. 58

§5.3.4 峰值应变随温度的变化规律 ............................. 59

§5.3.5 弹性模量随温度的变化规律 ............................. 61

§5.4 高频疲劳试验方案 ........................................... 62

§5.5 高频疲劳损伤模型与疲劳裂纹扩展规律 ......................... 63

§5.5.1 损伤变量 ............................................. 63

§5.5.2 损伤演化方程 ......................................... 64

§5.5.3 疲劳裂纹扩展规律 ..................................... 66

§5.6 高频疲劳试验结果分析 ....................................... 68

§5.7 本章小结 ................................................... 70

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摘要：

摘要I摘要本文主要对受雨水浸泡、循环荷载作用的混凝土、含裂纹体岩石及高温后岩石的疲劳变形和破坏机理进行了试验研究，探讨了水浸泡、疲劳荷载作用对混凝土力学性能的影响，分析了含裂纹体岩石材料的破坏机理，研究了含裂纹体岩石材料的高频疲劳特性，建立了水浸泡混凝土损伤本构模型以及高温条件下岩石疲劳破坏的准则和模型。在实际工程中，许多混凝土结构经常在水环境下工作，混凝土中含有大量的孔隙，包括混凝土成型时残留下来的气泡，水泥石中的毛细管孔腔和凝胶孔，以及水泥石和集料接触处的孔穴等。在水压力的作用下，水将渗透到混凝土的孔隙和裂缝中。受各种荷载的影响，混凝土中的孔隙水会对孔壁产生水压力，进而影响混凝土的力学性能...

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