沥青与集料间的黏附作用是形成沥青混合料结构的重要影响因素,且直接关系到沥青混合料的结构强度、水稳性等主要性能,也对沥青混凝土路面的使用寿命有较大影响。因此,对沥青与集料间黏附作用方面的研究十分必要。典型的黏附作用评价方...沥青与集料间的黏附作用是形成沥青混合料结构的重要影响因素,且直接关系到沥青混合料的结构强度、水稳性等主要性能,也对沥青混凝土路面的使用寿命有较大影响。因此,对沥青与集料间黏附作用方面的研究十分必要。典型的黏附作用评价方法可分为如下三类:(1)在石质基材(或其他材料)表面涂抹沥青层,对沥青层与基材界面施加垂直拉力或剪切应力,以沥青从基材表面剥离所需力的大小(或剪切强度)间接表征两者之间的黏附作用;(2)表面涂覆沥青的集料放入水中,水的作用使得沥青从集料表面剥落,以沥青从集料表面剥落的程度评价沥青与集料之间的黏附作用;(3)基于表面能理论,测试沥青与集料的表面能参数,从能量角度评价沥青-集料的黏附作用。我国《公路工程沥青及沥青混合料试验规程》(JTG E20-2011)中规定使用水煮法和水浸法来评价沥青-集料黏附性能,试验方法简单快捷,但测试结果受人为判断影响,缺乏定量评价指标。随着科学技术的进步,研究者逐渐将各种新技术运用到沥青-集料黏附性能检测中,如超声波模拟动水压力对传统水煮法进行改进,并应用高质量的图形处理系统使得沥青剥落程度指标得到更精准的量化;基于原子力显微镜技术(Atomic force microscope,AFM),在不同测试模式下进行微纳观尺度沥青-集料黏附作用评价,国外研究人员还依托神经网络模型,实现黏附性能的量化。随着原子力显微镜技术(AFM)的不断成熟,将该技术应用于对沥青-集料黏附作用的评价中已成为近年来的研究热点。同时,在研究人员的努力下,使用AFM新发展起来的测试模式测量沥青、集料的表面能及黏附功已取得突破性进展。随着对黏附作用研究的不断深入,一些研究新思路也开始出现,研究人员为了探讨在不同荷载作用下沥青与集料黏附性能的变化,针对“三明治”柱�展开更多
Rock engineering is highly susceptible to cyclic loads resulting from earthquakes,quarrying or rockbursts.Acquiring the fatigue properties and failure mechanism of rocks is pivotal for long-term stability assessment o...Rock engineering is highly susceptible to cyclic loads resulting from earthquakes,quarrying or rockbursts.Acquiring the fatigue properties and failure mechanism of rocks is pivotal for long-term stability assessment of rock engineering structures.So far,significant progress has been gained on the mechanical characteristics of rocks subjected to cyclic loading.For providing a global insight of typical results and main features of rocks under cyclic loading conditions,this study comprehensively reviews the state-ofthe-art of deformation and failure mechanism and fatigue constitutive relationship of rocks subjected to cyclic loading in the past 60 years.Firstly,cyclic tests on rocks are classified into different types based on loading paths,loading parameters,loading types and environment conditions.Secondly,representative results are summarized and highlighted in terms of the fatigue response of rocks,including the deformation degradation,energy dissipation,damage evolution and failure characteristics;both laboratory testing and numerical results are presented,and various measurement techniques such as X-ray microcomputed tomography(micro-CT)and digital image correlation(DIC)are considered.Thirdly,the influences of cyclic loads on the mechanical characteristics of rocks are discussed,including the cyclic stress,frequency,amplitude and waveform.Subsequently,constitutive relationships for rocks subjected to cyclic loading are outlined,in which typical fatigue constitutive models are compared and analyzed,regarding the elastoplastic model,the internal variable model,the energy-based damage model and the discrete element-based model.Finally,some ambiguous questions and prospective research are interpreted and discussed.展开更多
文摘沥青与集料间的黏附作用是形成沥青混合料结构的重要影响因素,且直接关系到沥青混合料的结构强度、水稳性等主要性能,也对沥青混凝土路面的使用寿命有较大影响。因此,对沥青与集料间黏附作用方面的研究十分必要。典型的黏附作用评价方法可分为如下三类:(1)在石质基材(或其他材料)表面涂抹沥青层,对沥青层与基材界面施加垂直拉力或剪切应力,以沥青从基材表面剥离所需力的大小(或剪切强度)间接表征两者之间的黏附作用;(2)表面涂覆沥青的集料放入水中,水的作用使得沥青从集料表面剥落,以沥青从集料表面剥落的程度评价沥青与集料之间的黏附作用;(3)基于表面能理论,测试沥青与集料的表面能参数,从能量角度评价沥青-集料的黏附作用。我国《公路工程沥青及沥青混合料试验规程》(JTG E20-2011)中规定使用水煮法和水浸法来评价沥青-集料黏附性能,试验方法简单快捷,但测试结果受人为判断影响,缺乏定量评价指标。随着科学技术的进步,研究者逐渐将各种新技术运用到沥青-集料黏附性能检测中,如超声波模拟动水压力对传统水煮法进行改进,并应用高质量的图形处理系统使得沥青剥落程度指标得到更精准的量化;基于原子力显微镜技术(Atomic force microscope,AFM),在不同测试模式下进行微纳观尺度沥青-集料黏附作用评价,国外研究人员还依托神经网络模型,实现黏附性能的量化。随着原子力显微镜技术(AFM)的不断成熟,将该技术应用于对沥青-集料黏附作用的评价中已成为近年来的研究热点。同时,在研究人员的努力下,使用AFM新发展起来的测试模式测量沥青、集料的表面能及黏附功已取得突破性进展。随着对黏附作用研究的不断深入,一些研究新思路也开始出现,研究人员为了探讨在不同荷载作用下沥青与集料黏附性能的变化,针对“三明治”柱�
基金the financial support from the National Natural Science Foundation of China(Grant Nos.52039007 and 52009086)the Sichuan Province Youth Science and Technology Innovation Team,China(Grant No.2020JDTD0001).
文摘Rock engineering is highly susceptible to cyclic loads resulting from earthquakes,quarrying or rockbursts.Acquiring the fatigue properties and failure mechanism of rocks is pivotal for long-term stability assessment of rock engineering structures.So far,significant progress has been gained on the mechanical characteristics of rocks subjected to cyclic loading.For providing a global insight of typical results and main features of rocks under cyclic loading conditions,this study comprehensively reviews the state-ofthe-art of deformation and failure mechanism and fatigue constitutive relationship of rocks subjected to cyclic loading in the past 60 years.Firstly,cyclic tests on rocks are classified into different types based on loading paths,loading parameters,loading types and environment conditions.Secondly,representative results are summarized and highlighted in terms of the fatigue response of rocks,including the deformation degradation,energy dissipation,damage evolution and failure characteristics;both laboratory testing and numerical results are presented,and various measurement techniques such as X-ray microcomputed tomography(micro-CT)and digital image correlation(DIC)are considered.Thirdly,the influences of cyclic loads on the mechanical characteristics of rocks are discussed,including the cyclic stress,frequency,amplitude and waveform.Subsequently,constitutive relationships for rocks subjected to cyclic loading are outlined,in which typical fatigue constitutive models are compared and analyzed,regarding the elastoplastic model,the internal variable model,the energy-based damage model and the discrete element-based model.Finally,some ambiguous questions and prospective research are interpreted and discussed.
