基于PNN模型和RF模型的沥青路面使用性能预测研究

如何准确地预测评断沥青路面使用性能,对于道路养护起着至关重要的作用。为了提出更为准确的路面使用性能评价方法,在规范所提出的评价指标的基础上,以临沂市的沥青路面使用评价相关数据为研究对象,分别基于概率神经网络（PNN）模型和随机森林（RF）模型,构建沥青路面使用性能预测模型,以此为沥青路面使用性能状态预测、科学制定沥青路面养护决策提供参考。     

高速公路沥青路面养护对策选择研究

本研究以河北省已建成的高速公路为工程依托,提出适合高速公路的路面使用性能评价标准,并根据河北省高速公路的实际情况,确定高速公路沥青路面标准养护处治对策等.根据评价标准和养护对策集,建立了高速公路沥青路面养护对策选择表和养护决策树模型.     

广西地区高速公路沥青路面养护措施评价研究

针对目前广西地区高速公路沥青路面养护状况,文章依托实体工程,通过路面养护数据和使用性能检测数据的收集、整理和分析,对微表处、不同厚度的铣刨重铺等常用沥青路面养护措施的使用效果进行评价,其对广西地区高速公路沥青路面养护方案的制定具有借鉴意义。     

沥青路面超薄粘结磨耗层预防性养护效果评价研究

为研究沥青路面超薄粘结磨耗层的预防性养护效果,文章以某高速公路实施超薄粘结磨耗层罩面预防性养护施工为背景,对各检测路段在预养施工前后及工后半年的路面车辙深度、行驶质量、抗滑性能、使用性能等进行对比评价分析。结果表明,超薄粘结磨耗层能够改善路面的车辙状况,提高路面的行驶质量、抗滑性能与使用性能。     

公路沥青路面裂缝养护技术分析研究

近年来,我国公路建设经过优化,多数公路路面已由原来的水泥路面转换为沥青混凝土路面.与以往的水泥路面相比,沥青混凝土路面具有优良的使用性能,因此,得到了大量推广.但就沥青路面而言,沥青混凝土在使用过程中,如施工技术以及后续养护不到位,便会发生路面裂缝,影响公路的正常使用.本文将就公路沥青路面裂缝养护技术分析展开讨论,阐述公路沥青路面裂缝养护必要性,分析如何运用有效的技术对公路沥青路面裂缝进行养护.     

沥青路面预防性养护技术在公路养护中的应用研究

为保证公路路面使用性能,对公路沥青路面病害成因与形式进行了研究,探讨了各种预防性养护技术的应用效果,以期对提升路面养护质量起到积极的作用。     

沥青路面结构强度评价初探

路面结构强度评价是进行路面养护决策的重要依据,是路面管理系统的重要组成部分.沥青路面在使用过程中,其结构强度随累计轴载作用次数的增加而逐渐衰减,当路面的结构强度降低到一定程度时,就需要进行大中修补强,以恢复和提高使用性能.过早地对路面进行大中修,不能充分发挥路面的功能和潜力,而造成浪费;如果错过大中修的最佳时机,就会使路面结构严重破坏,增加资金投入和使用者费用.准确地评价沥青路面的结构性能,可以使我们掌握对路面进行大中修的最佳时机,为判定中长期养护规划打下基础.     

半刚性沥青路面结构强度综合评价方法研究

为进一步研究路面结构强度不同评价方法在广西地区半刚性沥青路面的适用性,文章通过FWD采集广西典型高速公路沥青路面指标,并通过现行养护规范法、水稳层底面应变法、模量衰减法、路表弯沉法计算评价路面结构强度。经验算对比,其强度系数、上水稳层底面拉应变和损伤度指标具有良好的对应关系,可为广西地区半刚性沥青路面结构强度评价的准确性、路面寿命评估与养护决策规划提供参考依据。     

沥青路面平整度影响因素控制

路面平整度是评价高等级公路路面使用性能的一个重要指标.针对影响沥青路面平整度的原因进行了分析,并对施工控制方面提出了相应的措施,来提高路面工程质量.     

基于沥青路面性能的预防性养护时机确定方法

文章结合我国公路事业发展的现状,提出了基于路面破损状况、路面透水性指标、路面车辙指标、路面平整度指标的综合评价指标体系,并给出沥青路面预防性养护时机的确定方法及对策。     

公路路面沥青综合表面处治层质量评价方法研究

文章基于公路路面沥青综合表面处治试验路段性能指标检测,确定使用构造深度和饱和度评价公路路面沥青综合表面处治的使用性能,并利用主成分分析法对公路路面沥青综合表面处治层进行了质量评价。结果表明,该评价方法是合理、可行的。     

沥青混凝土路面预防性养护综述

根据不同路面损坏情况,综合阐述了预防性养护的技术措施,介绍了基于道路性能指数、管理、效益及环境作为评价指标分析了预防性养护的评价方法。     

机场复合道面结构性能综合评价

文章介绍了基于HWD测试数据的机场道面结构性能评价实施方案,阐述了机场复合道面结构的参数反演原理、性能评价指标及流程,并结合华东某机场HWD检测数据,对机场复合道面结构参数反演、ACN-PCN强度评价、结构剩余寿命、结构适应性厚度等评价指标进行了详细分析。     

Expert systems in pavement management

This paper discusses the potential application of expert systems, a new information technology derived from artificial intelligence research, to pavement management. The principal focus concerns the development of such knowledge-based or expert systems for project-level analysis and design of pavement rehabilitation strategies. Particular emphasis is placed on the needs of locally managed highway systems, although many of the concepts are also more broadly applicable. The paper provides a brief overview of the evolution and application of expert systems. Several major issues in pavement management are discussed which strongly suggest the appropriateness of expert systems approaches. These issues include the role of computerized pavement management systems, the acquisition of pavement performance data and current procedures for pavement structural evaluation and design. Current research on PARADIGM, an integrated set of expert systems for pavement rehabilitation decision-making, is described. Finally, a PARADIGM component system consisting of an operational prototype expert system for pavement surface condition evaluation, is presented as an example.     

Safety Effects of Winter Weather: The State of Knowledge and Remaining Challenges

Abstract

In recent years, there has been growing recognition of the effects of weather on the surface transportation system. Although considerable work has been done in quantifying the effects of weather on the highway system, there is still much that remains unknown about the relationship between weather and highway system performance. This paper synthesizes the findings from some of the major efforts in this area. The review of existing studies found consistent patterns that adverse weather reduces traffic speed and increases crash frequencies, while fatal crashes are decreased. A table is then presented which estimates the change in crash frequency and vehicle travel speed resulting from various winter weather conditions, based on a synthesis of earlier work. To estimate the safety and speed adjustment factors of compacted snow, a severity index is also developed. Recognizing the lack of comparability between the results of the studies, the paper concludes with a detailed discussion of avenues for future research which could help to address some of the gaps which currently exist. These challenges include, but are no limited to: quantification of the dynamic layer, development of the relationship between pavement friction and the composition of the dynamic layer, evaluation of the effects of pavement friction on vehicle speed, and evaluation of safety effects of weather conditions above the pavement.     

水泥混凝土路面施工平整度控制标准及方法

平整度是水泥混凝土路面行车舒适性的重要指标,在路面施工质量控制、养护质量评价和工程交（竣）工验收中受到高度重视。文章介绍了三种不同的平整度检测方法,并对这三种检测方法与平整度检测指标之间的关系进行了研究,确定了相应的平整度标准偏差值,为施工平整度控制和工程项目验收提供参考。     

抗车辙半柔性复合路面高温稳定性能研究

高温稳定性是路面抗车辙的主要性能指标,文章通过对抗车辙半柔性复合路面高温稳定性研究,确定抗车辙半柔性复合路面的高温稳定性远优于普通沥青混凝土路面。     

多年冻土区公路路面路基管理系统设计

我国多年冻土地区公路受气温及水分变化等影响,公路病害发生严重。为了使公路养护部门合理利用资金,最大限度避免冻土病害,有必要建立冻土区公路路基路面评价预测系统。文章介绍了冻土区公路路基的评价指标和评价方法。在常规路基路面评价预测的方法上,还使用了马尔可夫等预测方法,以适合冻土区公路路面破坏机理复杂、影响因素多的实际情况。     

Development of distress condition index of asphalt pavements using LTPP data through structural equation modeling

Traditional pavement distress index such as the Pavement Condition Index (PCI) developed by U.S. Army Corps of Engineers determines coefficients of distresses based on subjective ratings. This study proposed an asphalt pavement distress condition index based on various types of distress data collected from the Long-Term Pavement Performance (LTPP) database through Structural Equation Modeling (SEM). The SEM method treated the overall distress index as a latent variable while various distresses were treated as endogenous and other influence factors such as age, layer thickness, material type, weather, environment and traffic, were exogenous observed variables. The SEM method modeled the contributions of various distresses as well as the influence of other factors on the overall pavement distress condition. Influences of age, layer thickness, material type, environment and traffic on the latent distress condition were in accordance with previous studies. Compared with previous attempts to model latent pavement condition index utilizing SEM method, more pavement condition measurements and influencing factors were included. Specifically, this study adopted the robust maximum likelihood estimator (MLR) to estimate parameters for non-normally distributed data and derived the explicit expression of latent variables with intercepts. A multiple regression prediction model was built to calculate an overall condition index utilizing those measured distress data. The established pavement distress index prediction model provided a rational estimation of weighting coefficients for each distress type. The prediction model showed that alligator cracking, longitudinal cracking in wheel path, non-wheel path longitudinal cracking, transverse cracking, block cracking, edge cracking, patch and bleeding were significant for the latent pavement distress index.