Bird’s-eye view of recycled solid wastes in road engineering

Recent trends in road engineering have explored the potential of incorporating recycled solid wastes into infrastructures that including pavements,bridges,tunnels,and accessory structures.The utilization of solid wastes is expected to offer sustainable solutions to waste recycling while enhancing the performance of roads.This review provides an extensive analysis of the recycling of three main types of solid wastes for road engineering purposes:industrial solid waste,infrastructure solid waste,and municipal life solid waste.Industrial solid wastes suitable for road engineering generally include coal gangue,fly ash,blast furnace slag,silica fume,and steel slag,etc.Infrastructure solid wastes recycled in road engineering primarily consist of construction&demolition waste,reclaimed asphalt pavements,and recycled cement concrete.Furthermore,recent exploration has extended to the utilization of municipal life solid wastes,such as incinerated bottom ash,glass waste,electronics waste,plastic waste,and rubber waste in road engineering applications.These recycled solid wastes are categorized into solid waste aggregates,solid waste cements,and solid waste fillers,each playing distinct roles in road infrastructure.Roles of solid waste acting aggregates,cements,and fillers in road infrastructures were fully investigated,including their pozzolanic properties,integration effects to virgin materials,modification or enhancement solutions,engineering performances.Utilization of these materials not only addresses the challenge of waste management but also offers environmental benefits aiming carbon neutral and contributes to sustainable infrastructure development.However,challenges such as variability in material properties,environmental impact mitigation,secondary pollution to environment by leaching,and concerns regarding long-term performance need to be further addressed.Despite these challenges,the recycled solid wastes hold immense potential in revolutionizing road construction practices and fostering environmental stewardship.This review delves into a bird’seye view of the utilization of recycled solid wastes in road engineering,highlighting advances,benefits,challenges,and future prospects.

Effects of freeze-thaw cycle on engineering properties of loess used as road fills in seasonally frozen ground regions,North China

Compacted loess is widely used as fills of road embankments in loess regions of northern China.Generally, densely-compacted loess can satisfy the requirements of embankment strength and postconstruction deformation. However, uneven subsidence, pavement cracks and other related damages can affect the integrity of loess subgrade after several years of operation,and even cause some hazards, especially in North China, where the strong freeze-thaw erosion occurs. In this study, cyclic freeze-thaw tests for both densely and loosely compacted loess samples were performed to determine the variation in engineering properties such as volume, void ratio, collapsible settlement,microstructure, and the related mechanisms were addressed. The experimental results showed that an obvious water migration and redistribution occurred within the samples during freeze-thaw cycles. Ice lenses and fissures could be identified in the upper frozen layers of the samples. After freeze-thaw cycles,the dry densities of the upper layers of samples changed significantly due to strong freeze-thaw erosion. The dry densities decreased for the dense sample and increased for the loose sample. It can be found that dense samples become loose, while loose samples became dense with the increasing number of freeze-thaw cycles. Their related void ratios changed reversely. Both void ratios tended to fall into a certain range, which verified the concept of a residual void ratio proposed by Viklander. The loosening process of densely compacted samples involves the formation of large pores, volume increase and density reduction as well as the related changes in mechanical properties because freeze-thaw cycles may be important contribution to problems of loess road embankments.Adverse effects of freeze-thaw cycles, therefore,should be taken into account in selecting loess parameters for the stability evaluation of road embankment in seasonally frozen ground regions.

Perceived Benefits of Using Value Engineering on Road Projects in Ghana

The need for Optimum Value benefit realization on Road Projects in developing countries has become topical. While the traditional Cost Control project management process only aligns actual costs with budgeted costs, Value Engineering (VE) is a sustainable and systematic innovative methodology for establishing the best functional balance among desired features of a project. A Value Engineering (VE) study was conducted with the aim of examining the benefits associated with its use on Road Projects in Ghana. This study employed a two-stage research procedure: desk study and field research. The literature review identified the Optimum Value benefits associated with VE road project management technique as increased Confidence Level in Contract Compliance, reliable Implementation Level of Construction Delivery and enhanced Effectiveness Level of Project Sustainability. A quantitative survey research design based on a purposive sampling technique of selecting respondents was adopted. Employing closed-ended questions, 40 sets of questionnaires were issued to professionals in Road Infrastructure and Support Agencies (RISA) under the Ministry of Roads and Highways (MRH) in the Eastern Region of Ghana. At a response rate of 85%, descriptive statistical analysis (Means, Standard Deviations and Variances) and inferential statistical analysis of variance (ANOVA) test were used to process the data and determine whether there was any significant difference between VE benefit parameters and the groups of respondents. The results revealed that road professionals are familiar with the VE process but solely use Cost Control project management technique. Road professionals recognized the high Optimum Value benefits of professionally ethical Contract Compliance, efficient Construction Delivery and functionally viable Project Sustainability on VE road project management process.

Control Points of the Compaction Technology for Subgrades and Pavements in Municipal Road Engineering

With the rapid development of current social economy,China’s infrastructure construction is constantly increasing.The development of transportation industry and road structure which serve as infrastructure facility for the vehicles are fundamental aspect in economy growth.It’s not only convenience to people for travel,but also as a good foundation for the development of economy.Therefore,the quality of road construction is of great significance importance in the process of development.As technology advances,engineering construction is continuously expanding,especially in the road engineering sector.In this point,it’s necessary to impose strict quality control over related matters and ensure the quality and safety of municipal road construction.In the construction of municipal road engineering,one of the most important components is the compaction of subgrades and pavements,which requires more supervision.The compaction should match the requirements of road design and implement relevant work.

Cause and Prevention Measures of Concrete Cracks during the Construction of Road and Bridge Engineering

Road and bridge engineering is an indispensable part of socialist economic construction in China, whose construction quality significantly affects the infrastructure construction level in the whole society. To meet the rapid economic development of various regions, construction scale and quantity of road and bridge engineering have been continuously expanded and increased, therefore, higher requirements for construction quality and construction standard are also presented. During the construction of road and bridge engineering, concrete crack is a key problem which affects the construction quality. In this regard, this paper analyzes cause and prevention measures of concrete cracks during the construction of road and bridge engineering, and hopes to provide construction personnel with valuable references.

Analysis of Common Diseases and Construction Treatment Technologies of Road and Bridge Engineering

In recent years, the rapid growth of the number of private cars has greatly increased the traffic pressure, so the quality of roads and bridges should be further improved. The paper expounds the related matters of road and bridge engineering from three aspects. Firstly, it expounds the construction principles of road and bridge engineering, which are regarded as the theoretical basis of follow-up research. Secondly, it analyzes the common diseases of road and bridge engineering, including bridgehead damage, rein-forcement corrosion, and subgrade uneven settlement, etc. Finally, it puts forward the construction treatment technology of road and bridge engineering on the basis of the construction principles and taking the common diseases as reference.

Application of Construction Waste Recycled Material Processing in Road Engineering

In order to promote the recycling of construction waste in China and reduce the cost of road engineering materials,this paper expounds on the technical indexes,road performance,durability,and the impact on the compressive strength of road engineering of construction waste recycled materials based on the analysis of the processing technology of construction waste recycled materials to provide reference for future research.

Innovation of Engineering Surveying Course Teaching for Road and Bridge Engineering Technology Majors in Higher Vocational Colleges

Engineering surveying is an important course for road and bridge engineering technology majors in higher vocational colleges.With the advancement of science and technology,engineering surveying technology is also constantly developing,so the theoretical knowledge and professional skills that students need to master are also becoming increasingly complicated.To stimulate the students’interest in learning the course,it is necessary to continuously introduce innovative teaching methods into the course.In this paper,the importance of teaching innovation in engineering surveying courses of road and bridge engineering technology majors in higher vocational colleges and the knowledge system that students need to master are analyzed.Subsequently,innovative strategies are proposed to help improve the students’mastery of engineering surveying.

Application of BIM + Virtual Simulation Technology in Road Engineering Construction Technology and Organization Course

We focus on the goal of undergraduate talent training,consider the course features of Road Engineering Construction Technology and Organization,analyze the problems existing in the practical teaching of the course,use the advantages of BIM+virtual simulation technology,design a scientific and reasonable practical teaching content of Road Engineering Construction Technology and Organization,and address the contrast between the strong practical aspect of the traditional Road Engineering Construction Technology and Organization course and the lack of practical instruments in hope to improve students’learning autonomy,enhance the quality of practical teaching,achieve the training objectives of the course,and nurture applied technical talents.

Integration optimization of novel electric power steering system based on quality engineering theory

The dynamic model of a novel electric power steering （EPS） system integrated with active front steering function （the novel EPS system） is built. The concepts and quantitative expressions of the steering road feel, steering sensibility, and steering operation stability are introduced. Based on quality engineering theory, the optimization algorithm is proposed by integrating the Monte Carlo descriptive sampling, elitist non-dominated sorting genetic algorithm （NSGA-II） and 6-sigma design method. With the steering road feel and the steering portability as optimization targets, the system parameters are optimized by the proposed optimization algorithm. The simulation results show that the system optimized based on quality engineering theory can improve the steering road feel, guarantee steering stability and steering portability and thus provide a theoretical basis for the design and optimization of the novel electric power steering system.

Belt and Road Creates A New Engine of Economic Growth for Countries in Europe,Asia and Africa

The impact of the Belt and Road has continued to spread.Especially in the post-pandemic era,China and countries in Europe,Asia and Africa have restored their production capacities to build new engines for economic growth.This will inject new momentum into the economic growth of countries along the Belt and Road region.

Derivation of a Representative Engine Duty Cycle from On-Road Heavy-Duty Vehicle Driving Data

The heavy-duty vehicle fleet involved in delivering water and sand makes noticeable issues of exhaust emissions and fuel consumption in the process of shale gas development. To examine the possibility of converting these heavy-duty diesel engines to run on natural gas-diesel dual-fuel, a transient engine duty cycle representing the real-world engine working conditions is necessary. In this paper, a methodology is proposed, and a target engine duty cycle comprising of 2231 seconds is developed from on-road data collected from 11 on-road sand and water hauling trucks. The similarity of inherent characteristics of the developed cycle and the base trip observed is evidenced by the 2.05% error of standard deviation and average values for normalized engine speed and engine torque. Our results show that the proposed approach is expected to produce a representative cycle of in-use heavy-duty engine behavior.

Design Method for Road Reconstruction and Expansion

This article analyzes the method for designing routes in road reconstruction and expansion projects,using an actual engineering project as an example.This includes an overview of a specific road reconstruction and expansion project,an analysis of the preexisting road,the basic principles of the design road project,and an analysis of the design methods and steps.This study aims to offer some guidance for road reconstruction and expansion design.

内置应变传感器对沥青混合料力学性能的影响

道路本体结构的智能智慧是道路工程发展的重要方向,内置应变传感器是实现路面结构应变感知的重要手段,为探究内置应变传感器对沥青混合料力学性能影响,运用离散元法,构建了内置应变传感器的沥青混合料细观模型,研究了应变传感器埋设深度和数量对沥青混合料力学性能影响,分析了沥青混合料材料公称最大粒径、级配和沥青砂浆黏结强度等对内置应变传感器工作性能影响.结果表明:随着传感器埋设深度的增加,梁试件底部三个监测点位处水平拉应力分别增加56.9%、43.5%、43.8%,越接近梁试件底部,其内部水平应力场分布更均匀;与单传感器相比,埋设双传感器的梁试件裂隙增加速度更快,在挠度为0.8 mm时裂隙数便达到267个,单传感器仅为93个;沥青混合料公称最大粒径越大,力链数越少,AC-16、AC-20的平均力链比较AC-13分别降低4.9%、11.4%;沥青混合料级配越粗,荷载传递路径越少,接触力系数量减少77.7%,接触力分布均匀性降低,最大接触力增加74.6%,导致传感器工作稳定性越差;沥青砂浆黏结强度增加,最大接触力下降11%,传感器工作稳定性越好.研究结果可为提升内置应变传感器的沥青混合料耐久性和工作稳定性提供参考.

Hi-RTK Road在道路施工测量教学中的应用

GPS RTK定位技术以其测量精度高、布网灵活、操作方便的优势,在公路测量领域有着广泛的应用,也是道桥专业技术人员应该掌握的基本技能之一。本文以大连海洋大学道桥专业为例,对测量实践教学环节中应用GPS RTK技术进行了探索,并介绍了应用Hi-RTK Road软件开展道路施工测量实习教学的具体做法,对于普通高校应用型人才培养具有重要的借鉴意义。

Review of advanced road materials, structures, equipment, and detection technologies

As a vital and integral component of transportation infrastructure,pavement has a direct and tangible impact on socio-economic sustainability.In recent years,an influx of groundbreaking and state-of-the-art materials,structures,equipment,and detection technologies related to road engineering have continually and progressively emerged,reshaping the landscape of pavement systems.There is a pressing and growing need for a timely summarization of the current research status and a clear identification of future research directions in these advanced and evolving technologies.Therefore,Journal of Road Engineering has undertaken the significant initiative of introducing a comprehensive review paper with the overarching theme of“advanced road materials,structures,equipment,and detection technologies”.This extensive and insightful review meticulously gathers and synthesizes research findings from 39 distinguished scholars,all of whom are affiliated with 19 renowned universities or research institutions specializing in the diverse and multidimensional field of highway engineering.It covers the current state and anticipates future development directions in the four major and interconnected domains of road engineering:advanced road materials,advanced road structures and performance evaluation,advanced road construction equipment and technology,and advanced road detection and assessment technologies.

基于Artificial Engines的三维交通仿真系统的设计

三维交通仿真是对可视化交通管理系统进行分析和评价的一个有效方法,也是智能交通系统的一个重要研究方向.本文使用Artificial Engines这种托管3D引擎技术,通过由道路数据自动生成大规模三维路网场景,以及车辆运动算法,建立起一种可视化、实时高效的三维交通管理系统.

Review on constitutive models of road materials

Road material constitutive model is the essential condition of pavement structure design,calculation,and maintenance decision.Experts have conducted in-depth studies on the problems and proposed many meaningful constitutive models.However,these constitutive models have not been summarized and no uniform conclusion on the applicability of them is reported in the academic circle.The linear elastic model based on Hooke's law is still used in pavement structure design.This paper systematically reviewed the existing constitutive models that reflect the materials'mechanical properties and used for pavement structure calculation.These constitutive models were divided into three categories:linear,nonlinear,and damage models under repeated loads.The applicable conditions,parameter determination methods,advantages,and disadvantages of each model were introduced.Moreover,the model's feasibility in structural design and calculation was analyzed.Follow-up studies should focus on the parameter determination standard of viscoelastic constitutive models,the extension of the 1D constitutive model to 3D state,and the nonlinear constitutive models related to stress-strain state to drive the application of the constitutive models in pavement structure calculation and design.Furthermore,to evaluate the life cycle service performance of road materials and structures,establishing the pavement damage model from the structure perspective will be the future direction.

基于ArcGIS Engine的路网运行状态判别系统设计与实现

以GPS信息技术为基础,提出了基于ArcGIS Engine的道路交通状态判别系统的设计目标,分析了系统的总体框架、软件体系结构以及系统工作流程;根据系统的数据需求和功能需求,利用ArcGIS进行系统的数据库设计和功能模块设计.最后根据淄博市张店区主要道路的浮动车数据,完成了系统基本功能的开发.

Roadbed Subsidence Mechanisms under the Driven of Penetration-Soak Coupling

Roadbed subsidence is one of the main types of highway flood damage, the periodic fluctuation of the river water level and the softening of the subgrade soils by the river water immersion for a long time are the main inducement factors of the subgrade subsidence. Based on the theory of absorbing water infiltration in unsaturated soil, calculation formula of dynamic stability coefficient of subgrade is established by using the Swedish arc method. Example analysis shows that, soil roadbed suffers the water permeability-soak, road-bed’s stability reduce with the time, and leads to roadbed subsidence. Research results for improving roadbed subsidence water logging mechanism understanding level have a positive meaning.