隧道路面不设基层时水泥混凝土板的应力分析

文章通过建立不设基层的隧道水泥混凝土路面的分析模型,运用三维有限元分析方法,对隧道路面不设基层时在不同基岩模量和轴载下的弯拉应力进行分析,判断在何种基岩模量下可以不用铺筑基层而能保持水泥混凝土板不出现弯拉强度不足的情况。从而可以充分利用基岩的高强度,减薄路面总的厚度,节省造价。     

水泥混凝土路面设计与施工规范出新理论

日前,西部交通建设科技项目（《水泥混凝土路面基层长期性能研究》通过鉴定验收。经过长安大学、交通运输部公路科学研究院等单位组成的项目组研究,该项目取得了多项创新成果：水泥混凝土路面基层长期性能评价模型,设置层间功能层的水泥混凝土路面结构,沥青混凝土功能层的技术要求、设计指标与设计方法,适应不同交通与环境要求的水泥混凝土路面基层材料组成与结构设计方法,以及完善的设置层间功能层的水泥混凝土路面结构设计方法。     

隧道沥青路面环保铺筑技术研究

针对隧道沥青路面铺筑施工中存在的环境污染问题和路面结构的耐久性问题,《隧道沥青路面环保铺筑技术研究》课题开展了温拌降粘材料开发和使用性能研究与沥青路面施工过程中的通风技术研究,以减少隧道沥青路面铺装过程中的环境污染(包括施工过程污染和路面使用期间污染)、降低施工难度;同时研究了隧道沥青路面结构水泥混凝土基层与沥青层间的适宜粘结型式,力争提高隧道路面的使用耐久性。文章对该课题研究的内容、技术路线、试验方法及经济社会效益进行介绍,为隧道沥青路面铺筑施工提供借鉴。     

水泥混凝土路面断板的预防及处理

水泥混凝土路面是一种刚度大、扩散荷载能力强、稳定性好的路面结构。由于路面经常受重交通荷载、环境条件等外部作用,致使水泥混凝土路面产生不规则的断缝(断板)。从而使水泥混凝土路面使用性能下降,影响公路运输的效益和行车安全,因此,必须采取措施,加强对水泥混凝土路面断板的预防及处理。     

浅谈水泥混凝土路面施工质量控制

从水泥混凝土路面板材料的控制、施工前的准备工作和施工程序控制等方面阐述水泥混凝土路面施工质量的控制.     

水泥混凝土路面施工技术在公路工程中的应用

笔者结合施工经验,从论述公路工程水泥混凝土路面施工技术的基本含义出发,分别阐述了混凝土施工前的准备工作、水泥混凝土路面施工技术等方面,探讨了公路工程施工中水泥混凝土路面施工技术的应用,以供参考.     

水泥混凝土路面病害处理措施与防治对策分析

文章结合作者的工作实践积累,对汕尾市公路工程监督检查过程中发现的水泥混凝土路面出现的病害及产生原因进行分析,提出了处理措施及防治水泥混凝土路面病害的方法,旨在为实际工作提供参考。     

城市道路路面结构选型

通过对路面的材料特性、使用性能、施工技术、工程造价等多因素对比分析,对水泥混凝土路面、沥青混凝土路面进行综合技术经济评价,以确定道路的路面结构类型.     

高速公路隧道路面加铺材料研究

文章以来宾至马山高速公路、马山至平果高速公路为例,对高速公路长隧道水泥路面加铺结构进行了研究,在不破坏隧道原路面的原则上,采用快速便捷不影响交通的加铺手段改造原有水泥混凝土路面,提高隧道路面的抗滑性能和耐久度等性能。     

隧道内水泥混凝土路面渗漏水成因及病害处治

公路隧道内水泥混凝土路面受多种因素作用易出现渗漏水现象,严重影响行车安全。文章以某隧道水泥混凝土路面渗漏水病害处治为例,从地质水文条件、路面结构、防排水体系以及路面施工状况等方面,分析了隧道路面渗水成因,评定了渗水病害等级,并根据评定结果进行路面内部的排水引流结构设计,同时提出采用注浆和灌缝材料进行密封施工的处治方案。实例观测结果表明,渗涌水病害处治效果良好,路面通行效率得到提高,该处治方案与工艺可为富水山体公路隧道水泥混凝土路面涌渗水病害处治提供参考。     

多孔沥青混合料路面降温机理研究

如何降低路面高温、减少城市热岛效应影响成为了近年来一个较为关注的问题。文章通过分析多孔沥青混凝土路面的热环境,提出多孔沥青混凝土路面的降温原理及方式。     

时间序列法预测沥青路面损坏状况指数研究

由于沥青路面损坏状况影响因素很多,因此要准确预测路面损坏状况较困难。文章采用时间序列法建立预测模型,结合同三高速公路（上海段）路面损坏状况的实测数据进行预测分析。分析结果表明时间序列法具有较高的预测精度和易修正性。     

Predicting asphalt pavement crack initiation following rehabilitation treatments

Prolongation of the service life of pavements requires efficient prediction of the performance of their structural condition and particularly the occurrence and propagation of cracking of the asphalt layer. Although pavement performance prediction has been extensively investigated in the past, models for predicting the cracking probability and for quantifying impacts of associated explanatory factors following pavement treatment, have not been adequately investigated in the past. In this paper the probability of alligator crack initiation following pavement treatments is modeled with the use of genetically optimized Neural Networks, The proposed methodological approach represents the actual (observed) relationships between of probability of crack initiation and the various design, traffic and weather factors as well as the different rehabilitation strategies. Data from the Long Term Pavement Performance (LTPP) Data Base and the Specific Pavement Study 5 (SPS-5) are used for model development. Results indicate that the proposed approach results in accurately predicting the probability of crack initiation following treatment; furthermore it provided information on the relationship between external factors and cracking probability that can help pavement managers in developing appropriate rehabilitation strategies.     

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.     

彩色沥青路面的应用与发展

彩色沥青路面作为功能性路面和景观道路,已引起了人们的广泛关注与重视.文章结合国内外彩色沥青路面的发展现状,介绍了彩色沥青路面的种类、设备、相关指标标准、配合比设计及施工工艺等,指出了彩色沥青路面目前存在的主要问题,为开展相关研究提供参考.     

不同沥青路面结构抵抗车辙性能理论计算分析

车辙是沥青路面早期损坏主要形式,特别在陡坡及超载的条件下,沥青路面车辙病害更为突出。文章拟定了5种沥青路面结构组成,建立有限元模型计算了各种沥青路面结构的力学参数,对各种路面结构抵抗车辙的性能进行了分析对比。     

广西复合式路面方案设计初探

文章探讨的复合式路面是一种优势互补、发挥地方资源优势的发展潜力巨大的路面结构形式。通过计算分析所得的三种复合式路面结构方案,均考虑了车辆的超、重载问题,可较好的适应目前重载交通的需要,对进行复合式路面的结构设计具有一定的参考价值。     

A joint bottom-up solution methodology for system-level pavement rehabilitation and reconstruction

We present a methodology for the joint optimization of rehabilitation and reconstruction activities for heterogeneous pavement systems under multiple budget constraints. The proposed bottom-up approach adopts an augmented condition state to account for the history-dependent properties of pavement deterioration, and solves for steady-state policies for an infinite horizon. Genetic algorithms (GAs) are implemented in the system-level optimization based on segment-specific optimization results. The complexity of the proposed algorithm is polynomial in the size of the system and the policy-related parameters. We provide graphical presentations of the optimal solutions for various budget situations. As a case study, a subset of California’s highway system is analyzed. The case study results demonstrate the economic benefit of a combined rehabilitation and reconstruction budget compared to separate budgets.     

Impact of environmental assessment and budgetary restrictions in pavement maintenance decisions: Application to an urban network

Road agencies are facing the challenges of aging pavements, deteriorating networks, and insufficient maintenance budgets. This study addresses two limitations in the current state of practice in pavement management. First, because the evaluation of maintenance strategies has traditionally focused on economic and technical aspects, it neglects the environmental impact of maintenance decisions. Second, current management systems often provide a unique, optimised pavement maintenance strategy based on a specific objective(s) and constraint(s). The main objective of the study is to analyse the effect of including environmental aspects and funding availability in the design of maintenance strategies. To achieve this objective, the study followed a three-step methodology. First, this study reviews existing practices on pavement maintenance and the criteria considered to trigger the application of maintenance treatments and their effects on pavement condition. Then, maintenance strategies are optimised considering three levels of budgetary capacity and a sustainable evaluation which incorporates technical, economic, and environmental aspects over the pavement lifecycle. Finally, a case study dealing with an urban pavement network in Chile is analysed. Results obtained from this case study show that an increment of 2% in maintenance budget allows to account for more sustainable maintenance decisions, such as cold in-place recycling and full-depth slab repair, whose greenhouse gas emissions are lower than other alternatives. Results also show that functional asphalt overlay and microsurfacing are more recommended in flexible pavements when budgetary restrictions are low, whereas recommended treatments for rigid pavements exhibit small variability with budgetary restrictions.