Application of Digital Technology in Road and Bridge Design

With the development and progress of science and technology,road and bridge design has experienced rapid development,from the initial manual drawing design to the popularity of Computer-Aided Design(CAD),and then to today’s digital software design era.Early designers relied on hand-drawn paper design forms which was time-consuming and error-prone.Digital support for road and bridge design not only saves the design time but the design quality has also achieved a qualitative leap.This paper engages in the application of digital technology in road and bridge design,to provide technical reference for China’s road and bridge engineering design units,to promote the popularity of Civil3D and other advanced design software in the field of engineering design and development,ultimately contributing to the sustainable development of China’s road and bridge engineering.

Sustainability of lime stabilized road subgrade in mountainous regions of Türkiye

In this paper the use of lime stabilized subgrade for low volume roads in two regions with high mountains and different frost penetration conditions in Türkiye was investigated in terms of design,performance,and cost.Pavements on unstabilized and stabilized subgrade were designed for two regions(Izmir and Van),covering all climate variations.The resilient modulus of the lime stabilized subgrade with different soil pulverization levels for non-freezing and freezing conditions were taken from a previous laboratory study.Frost effects were considered in pavement design using two different approaches,including limited subgrade frost penetration method and reduced subgrade strength method.Detailed application and evaluation were performed for all steps.Lime stabilized subgrades significantly reduced the thickness of base courses,and the benefit of lime stabilization was highly dependent on soil pulverization level.A detailed cost analysis on the unstabilized and stabilized cases found that the use of lime stabilization in the subgrade provided significant initial cost savings.Comparative analysis by using the AASHTO(1993)method and KENPAVE software,and quantity effect of soil pulverization level on the performance of low volume roads from a service life perspective,show that subgrade resilient modulus can be estimated.It is also possible to make correct performance estimation in the field.The results of the study show that lime stabilization is a good solution for low volume roads in the mountainous regions of Türkiye.

Determination of Main Design Indicators of Patrol Road in Nature Reserves

In principle,nature reserves are managed and controlled according to the core area and the general control area.At present,there is no relevant design specification for the design system of patrol road in various protected areas.This paper analyzed the factors to be considered in determining the grade,horizontal and vertical design indicators,and cross section indicators of the patrol road in the protected area,and came up with the corresponding design indicators and parameters,so as to provide a certain reference for the subsequent patrol road design.

Application Strategy of BIM Technology in Municipal Road Design

The development of information technology provides certain convenient conditions in the design of municipal roads,and allow the achievements of high standards and requirements of current road design and construction.Among many information technologies,building information modeling(BIM)technology is more widely used in road design and has achieved good results.BIM technology can realize information sharing,allow the design of virtual models,discover design problems in time,and reduce the rate of design changes later or in late stage.At the same time,through the coordination and standardization of the design of road traffic and underground pipelines,it provides new design ideas for the development of municipal roads.This paper mainly analyzes the application advantages and status of BIM technology in municipal road design,and puts forward the application strategy of municipal road design.

Application Strategy of Green Transportation Concept in Urban Road Design

Urban traffic and urban environmental pollution are important issues that must be taken into account in the process of urbanization,especially in China.Modernization has enabled many developed countries in the west to carry out rational city traffic planning.At the same time,the concept of green transportation has also emerged,integrating low-energy consumption,low pollution,comfort,and safety into urban traffic to effectively solve issues pertaining to traffic and pollution.The concept of green transportation has been widely adopted in China and made popular in many cities,thereby promoting the sustainable development of cities.

Overall Selection Design Based on the Mega Highway Bridge Project

In the continuous development of the modern highway and bridge engineering industry,the reasonable selection of mega highway bridges and their design is crucial.Based on this,this paper takes the actual bridge project as an example,and analyses the overall selection design of such highway bridges,including the basic overview of the project,the basic selection principle of mega highway bridge project structure and its design strategy,etc.,to provide scientific reference for its selection design.

The Application of Curriculum Ideological and Political Cases in the Teaching of Road Survey and Design

Ideological and political construction of curriculum is the key link to implement the fundamental task of moral education.Focusing on the training objectives of civil engineering professionals in the new era,combined with the teaching concepts of moral education and student-centered education,the teaching objectives for the course of road survey and design have been re-set.The implementation plan of ideological and political education has been put into practice by involving excellent engineering cases,stories of outstanding figures in this field,traffic accidents,design concepts and technological innovation to explore the methods of integrating ideological and political cases into curriculum teaching for a continuous improvement of the promotion of curriculum ideological and political education to the teaching quality of professional courses.

The Application of“Humanized”Concept in Urban Road Design

In order to promote the development of urban roads,enhance urban road design,and fully maximize the role of urban roads,this study first discusses the fundamental requirements of urban road design,the“humanized”concept in urban road design,and the importance of“humanized”urban road design,as well as proposes several“humanized”design strategies for urban roads as references.

ORD在斜坡式码头设计中的应用研究

针对斜坡式码头,采用Bentley数字化平台内专业线性建模软件Open Roads Designer(简称ORD)进行三维设计,可以高效实现地形及构筑物的三维模型的建立,直观形象展示工程全貌。同时支持动态访问功能,可以在设计全过程中提取三维可视化模型信息,实时进行斜坡式码头的线型选择、断面预览及工程量计算等操作,提高了设计工作效率,为今后将三维设计应用于斜坡式码头工程提供了参考。

Spatial Layout of Mountainous Elderly Residential Districts

Taking the planning of elderly building for example, this paper explored the spatial layout, entrance/exit design, road space design and landscape design of the elderly residential districts against the background of population aging and increasing demands of ecological residence. In addition, the paper tried to fully use outstanding natural environment in mountainous areas to plan the elderly community, and integrate the characteristics of mountainous community planning and elderly buildings.

Research on Application of Visual Simulation System of Expressway

Applying the visual simulation technology to highway engineering, an expressway visual simulation system for the analysis of landscape design proposals is built during the construction of Xiaoxiang expressway. Its functional requirements and overall architecture are presented. The 3D model of expressway is created with AutoCAD DWG files as source data and the dynamic design method of expressway landscape elements is introduced. A data analysis interface dedicated to the landscape evaluation is developed. The system offers an effective tool to facilitate the analysis and evaluation of the road landscape proposals.

Optimal Design of Two Road Networks Based on their Properties

In this paper, we discuss some fundamental properties of two idealized typical networks, namely, grid type and radial-circular type. The discussion is based on SPCP （Shortest Path Counting Problem）, which reflects the traffic density of a road segment. Furthermore, we compare their effectiveness based on the obtained results of the above two road networks, and suggest some proposals on the design of car lanes by considering the direction of a road segment in relation to these road networks.

Main flexible pavement and mix design methods in Europe and challenges for the development of an European method

Pavement and mix design represent one of the key components within the life cycle of a road infrastructure, with links to political, economic, technical, societal and environmental issues. Recent researches related to the characteristics of materials and associated behavior models both for materials and pavement, made it appropriate to consider updating current pavement design methods, and especially in the USA this has already been in process while in Europe uses of the methods developed in the early 1970s. Thus, this paper firstly presents a brief historical overview of pavement design methods, high- lighting early limitations of old empirical methods. Afterwards, French, UK and Shell methods currently in use in Europe will be presented, undeHining their main components in terms of methodology, traffic, climatic conditions and subgrade. The asphalt mix design and modeling in Europe are presented with their inclusion in the pavement design methods. Finally, the main challenges for the development of a European pavement design method are presented as well as the recent research developments that can be used for that method.

Influence of geometric design characteristics on safety under heterogeneous traffic flow

This paper focuses on analysing the influence of geometric design characteristics on traffic safety using bi-directional data on a divided roadway operated under heterogeneous traffic conditions in India. The study was carried out on a four lane divided inter-city highway in plain and rolling terrain. Statistical modelling approach by Poisson regression and Negative binomial regression were used to assess the safety performance as occurrence of crashes are random events and to identify the influence of the geometric design variables on the crash frequency. Negative binomial regression model was found to be more suitable to identify the variables contributing to road crashes. The study enabled better understanding of the factors related to road geometrics that influence road crash frequency. The study also established that operating speed has a significant contribution to the total number of crashes. Negative binomial models are found to be appropriate to predict road crashes on divided roadways under heterogeneous traffic conditions.

Sensitivity analysis of longitudinal cracking on asphalt pavement using MEPDG in permafrost region

Longitudinal cracking is one of the most important distresses of asphalt pavement in permafrost regions. The sensitivity analysis of design parameters for asphalt pavement can be used to study the influence of every parameter on longitudinal cracking, which can help optimizing the design of the pavement structure. In this study, 20 test sections of Qinghai-Tibet Highway were selected to conduct the sensitivity analysis of longi- tudinal cracking on material parameter based on Mechanistic-Empirical Pavement Design Guide （MEPDG） and single factorial sensitivity analysis method. Some computer aided engineering （CAE） simulation techniques, such as the Latin hypercube sampling （LHS） technique and the multiple regression analysis are used as auxiliary means. Finally, the sensitivity spectrum of material parameter on longitudinal cracking was established. The result shows the multiple regression analysis can be used to determine the remarkable influence factor more efficiently and to process the qualitative analysis when applying the MEPDG software in sensitivity analysis of longitudinal cracking in permafrost regions. The effect weights of the three parameters on longitudinal cracking in descending order are air void, effective binder content and PG grade. The influence of air void on top layer is bigger than that on middle layer and bottom layer. The influence of effective asphalt content on top layer is bigger than that on middle layer and bottom layer, and the influence of bottom layer is slightly bigger than middle layer. The accumulated value of longitudinal cracking on middle layer and bottom layer in the design life would begin to increase when the design temperature of PG grade increased.