沥青稳定碎石透水层在南方高速公路中的应用

沥青路面的水损坏已成为高速公路路面结构的主要病害之一,本文结合工程实例,详细分析设置下卧透水层的高速公路路基结构和构造形式特点,并结合试验路段施工,对采用沥青稳定碎石透水层的施工技术及效果检测进行了深入探讨,并对其路用性能和经济性进行了分析评价和总结。     

沥青稳定碎石排水层的设计

以高等级公路沥青路面的典型结构形式作为未设排水层的路面结构原型,通过不同的设置层位分析对排水层的回弹模量和厚度的要求,探讨设置排水层路面结构的一些结构参数适宜的取值范围,对不同设置层位的路面结构的技术指标进行比较分析,得出较优的层位设置方案。     

浅析高等级公路沥青稳定碎石排水层的设计

以高等级公路沥青路面的典型结构形式作为未设排水层的路面结构原型,通过不同的设置层位分析对排水层的回弹模量和厚度的要求,探讨设置排水层的路面结构的一些结构参数适宜的取值范围,并在此基础上运用灰色系统关联分析方法,对不同设置层位的路面结构的技术指标进行比较分析,得出较优的层位设置方案。     

高等级公路沥青稳定碎石排水层的设计

以高等级公路沥青路面的典型结构形式作为未设排水层的路面结构原型,通过不同的设置层位分析对排水层的回弹模量和厚度的要求,探讨设置排水层的路面结构的一些结构参数适宜的取值范围,并在此基础上运用灰色系统关联分析方法,对不同设置层位的路面结构的技术指标进行比较分析,得出较优的层位设置方案。     

浅析高等级公路沥青稳定碎石排水层的设计

以高等级公路沥青路面的典型结构形式作为未设排水层的路面结构原型,通过不同的设置层位分析对排水层的回弹模量和厚度的要求,探讨设置排水层的路面结构的一些结构参数适宜的取值范围,并在此基础上运用灰色系统关联分析方法,对不同设置层位的路面结构的技术指标进行比较分析,得出较优的层位设置方案。     

沥青路面新型水损害成因分析

通过对某高速公路半刚性基层沥青路面出现的早期水损害的调查和检测,重点对沥青路面一种新型的水损害--搓板产生的原因进行了分析,为设计和施工积累了经验,以期合理地选择处治方案.     

沥青混合料在施工过程中的离析现象分析

高速公路沥青路面早期水损害已成为我国高速公路沥青路面最主要的病害之一,如何进行有效地防治是目前公路工程师比较关心的问题。特别是施工过程中,本文通过对沥青混合料拌和与装卸料、运输过程产生的离析、摊铺过程产生的离析等多方面进行分析,对加强沥青路面水损害问题的研究具有较大现实意义与工程实用价值。     

沥青路面水稳定性机理及其防治措施

针对沥青路面水损害问题是公路工程的通病之一,从水损害产生的原因入手,对沥青路面水损害产生机理进行了较详细的分析,并针对性地提出了预防水损害出现的相应措施,从而减小沥青路面的损害。     

高速公路沥青路面水损害的防治措施

针对高速公路沥青路面的水损害问题,分析了造成沥青路面水损害的主要原因,从沥青混合料的级配组成、路面压实度、空隙率、路面排水、水稳定性等方面提出了具体的防治措施.     

市政道路沥青路面水损害成因及有效防治分析

介绍了公路工程中水损害路面结构的类型,分析了沥青路面水损害现象的产生原因,并从排水设施、结构设计、质量管理、超载控制等方面,提出了沥青路面水损害问题的防治措施,有利于延长公路的使用寿命。     

Effect of asphalt film thickness on the moisture sensitivity characteristics of hot-mix asphalt

Temperature, air and water are the common factors that profoundly affect the durability of asphalt concrete mixtures. In mild weather conditions, distresses such as permanent deformation, fatigue cracking can be encountered on the pavements due to traffic loading. But when a severe climate is in question, these stresses increase in poor materials; under inadequate control; with traffic as well as with water which are key elements in the degradation of asphalt concrete pavements. Many variables affect the amount of water damage in asphalt concrete layer. Among them, mixture design properties such as air void level, permeability, asphalt content and asphalt film thickness are the ones that must be investigated carefully.     

沥青路面水损害及防治对策

从分析水损坏现象的普遍性和水损坏危害的严重性入手，结合国内外研究成果，对水损坏现象的产生和作用机理、水损害产生的原因、水稳性的影响因素以及相互之间的影响进行了深入剖析，提出了预防沥青路面水损害的对策。     

浅谈长寿命沥青路面

指出长寿命路面是目前高等级公路路面结构选择和设计的新趋势,从结构特点、结构设计和结构损坏模式等方面对长寿命沥青路面进行了详细介绍,并对其进行了经济效益分析,从而促进长寿命沥青路面的研究和应用.     

Pore Pressure and Viscous Shear Stress Distribution Due to Water Flow within Asphalt Pore Structure

Abstract:   There has been a concentrated effort in modeling fluid flow in asphalt pavements, and most of the existing work has been limited to evaluation of directional permeabilities. The effects of other phenomena, such as development of flow-induced pore pressure and viscous shear stress distributions at the pore–solid interfaces, on moisture damage in an asphalt pore structure have not been fully understood. A three-dimensional (3D) numerical fluid flow model was developed using the lattice Boltzmann (LB) method to simulate water flow within the pore structures of various hot mix asphalt (HMA) pavements . In this article, an in-depth analysis of variations of pore pressures and viscous shear stresses caused by water flow within the 3D pore structure of different HMA specimens is provided. The relationship between the pore geometry and the pore water pressure and viscous shear stresses were studied. Pore pressures and viscous shear stresses were computed after 3D fluid flow simulations conducted within the real pore structures of numerous HMA specimens. X-ray computed tomography (CT) was used to acquire 3D pore structures of HMA specimens, and the obtained images were input into the LB model. The results indicated that the pore water pressure gradient is highly nonlinear within the pore structure of HMA pavements, as opposed to a linear gradient commonly observed in homogeneous pore structures (e.g., granular soils). The viscous shear stresses were observed to be the largest at the constrictions located at the mid-depth of the specimens. Furthermore, a one-to-one relationship was observed between the reduction in the pore area and viscous shear stresses developed during the water flow .     

考虑层间状态的沥青路面温度与荷载耦合行为分析

沥青路面是典型的层状体系,层间黏结状态的好差直接影响到路面的使用性能.采用三维非线性有限元软件ABAQUS,同时考虑沥青混合料的劲度模量随温度变化的特性,数值模拟计算了沥青路面在不同温度场状况下分别与水平及竖向荷载耦合作用的关键力学响应,分析各响应指标随层间接触状态变化的特性.研究结果表明由于接触模型作用机理的不同,其关键力学指标响应要比连续模型下的大;除路表竖向变形大小几乎与层间接触状态无关外,其他指标在低温状况下,层间接触条件变化对其影响较小,而在高温状况下,特别当层间接触摩擦系数μ＜0.6时影响很大,尤其对基层、底基层的最大拉应力及面层的最大剪应力影响显著.研究成果为科学解释沥青路面在不同环境温度与车辆荷载综合作用下的破损特征与行为机理提供了有力依据,为改善层问黏结条件有利于提高路面整体性能提供了理论支撑.     

沥青路面混合料离析的控制与预防

沥青混合料的离析是沥青路面铺筑过程中经常出现的问题,是引起沥青路面早期破坏的主要原因之一,该文结合离析产生的原因,阐述了在施工各个环节控制和预防沥青路面离析的有效措施。     

多孔沥青混凝土路面的调研分析

多孔沥青混凝土具有排水、降噪等优良性能,广泛应用于表面层。通过调研和整理,介绍了多孔沥青混凝土路面的起源、发展以及在我国的实践。同时,调研分析了多孔沥青混凝土路面的强度机理、降噪机理与排水机理。最后指出了未来多孔沥青混凝土的研究方向。     

沥青混凝土路面常见病害成因及处治措施

通过对沥青混凝土路面常见病害进行分析,揭示沥青混凝土路面病害产生的原因,提出沥青混凝土路面病害的预防及处治措施,以提高路面使用性能,延长沥青道路寿命。     

温拌沥青混合料的半圆弯抗与水敏感性试验研究

疲劳破坏和水损害是温拌沥青路面重要的破坏类型之一。采用由三个现场项目提供的8种温拌沥青混合料(Evotherm、Sasobit、Foamed),进行半圆弯抗(SCB)试验和改进Lottman试验(AASHTO T283)分别评价WMA的抗疲劳性能与水稳定性。结果表明:与相应的HMA比较, WMA表现出相近或更高的Jc值;WMA技术的使用提高了沥青混合料的抗断裂性能;温拌沥青混合料和普通热拌沥青混合料的水敏感性没有显著差异。     

Application of Markov chains and Monte Carlo simulations for developing pavement performance models for urban network management

Existing performance models developed for interurban pavements are not applicable to urban pavements due to differences in traffic demands and deterioration trends. The objective of the study was to develop performance models for the management of urban pavement networks. Markov chains and Monte Carlo simulation were applied to account for the probabilistic nature of pavements deterioration over time, using data collected in the field. One of the advantages of this methodology is that it can be used by local agencies with scarce technical resources and historical data. Eight performance models were developed and successfully validated for asphalt and concrete pavements in humid, dry and Mediterranean climates with different functional hierarchies. The resulting models evidence the impact of design, traffic demand, climate and construction standards on urban pavements performance. Predicted service life of asphalt and concrete pavements in primary networks are consistent with design standards. However, pavements in secondary and local networks present shorter and longer service life compared to design life, respectively. Climate is a relevant factor for asphalt pavements, where higher deterioration was observed compared to that expected. Opposite to this, no relevant differences between design and performance can be attributed to climate in concrete pavements.