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Stabilization of a Lateric Clay from Burkina Faso with Cement-Metakaolin for an Application in road construction

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Journal of Materials Science and Chemical Engineering 2023年第6期11卷 1-20页

作者： Souleymane Sanou Issiaka Sanou Moussa Ouedraogo Halidou Bamogo Lohami Valentin Landry Gnoumou Younoussa Millogo Seynou Mohamed Laboratoire de Chimie et Energies Renouvelables (LaCER) Département de Chimie Université Nazi BONI (UNB) Bobo Dioulasso Burkina Faso Laboratoire de Chimie Moléculaire et des Matériaux (LC2M) Département de Chimie Université Joseph KI-ZERBO (UJKZ) Ouagadougou Burkina Faso

The objective of this work is to obtain a composite of clay-cement-metakaolin having good mechanical properties and geotechnical. To do this, a lateritic clay from Burkina Faso referenced ALK was characterized by various methods (X-ray diffraction, infrared spectrometry, thermal analysis and Inductively Coupled Plasma, Atomic Emission Spectrometry) in order to be used as a base course after adding cement and metakaolin. The results of the mineralogical characterization of this clay showed that it is composed of kaolinite (65.7 wt.%), quartz (19.3 wt.%) and goethite (10.8 wt.%). The geotechnical tests carried out showed that ALK is moderately plastic with a plasticity index Ip = 22%. The optimum moisture content and the maximum dry density are respectively 15.9% and 1.76 g∙cm-3. Simple compressive strength and splitting tensile strength are Rc = 1.59 MPa and ft = 0.149 MPa respectively. The California Bearing Ratio (CBR) index at 95% is 40% and above the minimum value of 30% shows that ALK can be used as a sub-base course in road construction. The addition of cement and metakaolin in various proportions improved the CBR index and the mechanical strength of the composites produced. This improvement is due to the formation of hydrated calcium silicate (CSH) resulting from the pozzolanic reaction between the portlandite of the cement and the amorphous silica of the metakaolin. Thus the 2 wt.% metakaolin and 6 wt.% cement formulation with a 95%CBR index of 81% is suitable for the development of a base course in road construction.

关键词： Lateritic Clay Cement Metakaolin road construction The California Bearing Ratio Index

Evaluating the Impact of Workshop Management on the Progress of road construction Projects(Case Study:road construction Projects of Tehran Province)

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Journal of Management Science & Engineering Research 2023年第1期6卷 49-59页

作者： Morteza Modarresi Fatemeh Mousavi Islamic Azad University Ayatollah Amoli Branch***Iran Department of Forestry and Forest Economics Faculty of Natural ResourcesUniversity of Tehran***Iran

construction projects,including road construction,are very important.Therefore,a lot of money is spent on these projects every year.So,the lack of proper planning will increase the cost and cause irreparable damage to the country.The role of workshop management is one of the most important factors in increasing the cost of these types of projects.Generally,workshop management plays a very important role in improving the quality and quantity of projects and has an important place in the project implementation process.Therefore,this study evaluated the impact of workshop management on the progress of road construction projects on a case-by-case basis in road construction projects in Tehran province.According to the purpose of the research,this study was a descriptive-survey type.In addition,the tool used in this research was a questionnaire.The statistical population of this research included all experts and specialists in road construction projects,among whom 65 people were selected by snowball method.Then the collected data were analyzed using SPSS software.The results of this study showed that the management of the workshop and its role in the control and implementation of projects is a complex process,which can be implemented at high levels and effectively by combining scientific and experimental training.And a very important point in the discussion of workshop management is applying scientific management to the use of valuable experiences from others.Because management knowledge not only does not negate the use of these experiences,but also emphasizes the necessity of using them.In other words,improving the knowledge of workshop management is one of the requirements for the implementation of value engineering in construction projects,especially road construction,and it is very important.

关键词： construction projects Workshop management Snowball road construction

road construction and landscape fragmentation in China

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Journal of Geographical Sciences 2005年第1期15卷 123-128页

作者： LIShuangcheng ZHOUQiaofu WANGLei CollegeofEnvironmentalSciences PekingUniversity TheKeyLaboratoryforEarthSurfaceProcesses MinistryofEducationBeijing100871China

The landscape fragmentation caused by road construction has many direct and indirect impacts on wildlife and ecosystems. By using the GIS and statistic software of fragmentation computation, a comprehensive index, road-induced landscape fragmentation index (RLFI), is proposed to quantify the degree of landscape fragmentation resulting from different levels of road constructions. The results show that road-induced fragmentation index in China ranges from 0.987 to 3.357, with a mean of 1.846 in 2002. The regional differences of landscape fragmentation are obvious and scoring sequence is: North China (2.65) > East China (2.62) > Central China (2.60) > South China (2.51) > Southwest China (2.34) > Northeast China (2.19) > Inner Mongolia (1.88) > Northwest China (1.67) > Qinghai-Tibet Plateau (1.65). The anisotropic analysis indicates that the variation of fragmentation index in east-west direction is larger than that in south-north direction.

关键词： landscape fragmentation road construction China

Measurement of dust emission from a road construction using exposure-profiling method

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Natural Science 2013年第12期5卷 1255-1263页

作者： Jia Qi Al-Ansari Nadhir Knutsson Sven Department of Civil Environmental and Natural ResourcesDivision of Soil Mechanics and Foundation EngineeringLuleaSweden

road construction is one example of heavy constructions that may have a substantial temporary impact on local air quality. construction of Lule? road during the summer of 2013 generated a great deal of dust emission. US EPA recommended exposure-profiling method was used to measure dust emission. Inexpensive BSNE dust samplers were used instead of high volume samplers. The objective was to give a general idea of the amount of dust generated due to the construction work. Dust generation related to weather was discussed under conditions. Estimated threshold wind velocities for road surface materials at the height of 2 m were 12.88 m/s, 12.88 m/s and 24.76 m/s which were lower measured wind velocities, indicating no dust generated from wind erosion. Dust masses for 7 sampling periods show dust generation had a close relation with moisture content of surface material. Wind speed, humidity had minor or no effect. The estimated dust emission rate in the construction work during the measuring period was 22.86 kg TSP/d, 6 kg/d was from construction work and 16.86 kg/d was generated due to traffic on temporary roads.

关键词： Dust Emission road construction Exposure-Profiling BSNE

Advanced industrial informatics towards smart,safe and sustainable roads:A state of the art

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第2期10卷 143-158页

作者： Hui Yao Zijin Xu Yue Hou Qiao Dong Pengfei Liu Zhoujing Ye Xin Pei Markus Oeser Linbing Wang Dawei Wang Beijing Key Laboratory of Transportation Engineering Faculty of ArchitectureCivil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China Department of Civil Engineering Swansea UniversitySwansea SA28PPUK School of Transportation Southeast UniversityNanjing 211189China Institute of Highway Engineering RWTH Aachen UniversityAachen D52074Germany National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China Department of Automation Tsinghua UniversityBeijing 100084China School of Environmental CivilAgricultural and Mechanical EngineeringUniversity of GeorgiaAthensGA 30602USA School of Transportation Science and Engineering Harbin Institute of TechnologyHarbin 150006China

The road is one of the most important civil infrastructures for serving society,where its service quality and life have direct impacts on the safety and comfort of users.Therefore,road construction,condition detection and monitoring,and timely maintenance are particularly important for engineers.Many engineering applications of industrial informatics approaches,like image processing technology,widely used computer-based algorithms,and advanced sensors,have been initially and gradually applied to roads.This state-of-the-art review first summarized the research on industrial applications of advanced information technologies in recent years,while analyzing and comparing the advantages and disadvantages of each technology.Especially,five topics were focused on road construction,road maintenance with decision strategy,road structure evaluation,smart sensing in the road,and cooperative vehicle infrastructure system.It is expected that advanced industrial informatics can help engineers promote the development of smart,safe,and sustainable roads.

关键词： Advanced industrial informatics road construction road maintenance Decision strategy Pavement structure and material Smart sensing Cooperative vehicle infrastructure system

Effects of Tidal Channels and roads on Landscape Dynamic Distribution in the Yellow River Delta, China

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Chinese Geographical Science 2020年第1期30卷 170-179页

作者： YU Xiaojuan ZHANG Zhongsheng XUE Zhenshan WU Haitao ZHANG Hongri Shangdong University of Science and Technology Qingdao 266590China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 1301012China

Landscape characters in estuarine regions generally controlled by tidal regimes and human activities like road construction.In this work,tidal channels and road construction in the Yellow River Delta(YRD)were extracted by visual interpretation methods so as to decipher impacts of tidal channel development and road construction on landscape patch change during 1989–2016.Spatial distribution history of three wetlands,which covered by Phragmites australis(freshwater marsh,FM),Suaeda salsa(salt marsh,SM),and mudflats(MD)were also established.Results indicated that tidal channel,number,frequency,and fractal dimension were all the maximum in 2003,and the minimum in 1998,respectively.road length,number,and density showed increasing trend during 1989–2016.MD were the predominant landscape type,followed by FM and SM during 1989-2016.Principal component analysis implied two extracted factors,F1 and F2,which could represent 91.93% of the total variations.F1 mainly proxied tidal channel development,while F2 represented road construction.A multiple linear regression analysis showed positive effects of both F1 and F2 on FM patch numbers and negative impacts on SM patch areaes with R^2 values of 0.416 and 0.599,respectively.Tidal channels were negatively related to MD patch numbers,while roads were positively related to that.In any case,road construction showed larger impacts on landscape type shifting than that of tidal channel development in the YRD.

关键词： tidal channel development road construction principal component analysis multiple linear regression analysis the Yellow River Delta

Analysis of the Application of Windbreak and Sand Fixation Technology in Desert roads

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Journal of World Architecture 2023年第4期7卷 45-50页

作者： Qianrong Yang China Merchants Chongqing Communications Technology Research&Design Institute Co. LTD.Chongqing 400067China

In order to solve the problems in the construction of desert roads and improve the quality of desert roads in China,this paper discusses the current windbreak and sand fixation technologies in desert areas in China,and puts forward relevant suggestions and corresponding solutions for each problem.This paper is written with hopes of contributing to the development of windbreak and sand fixation technologies in China as well as the development of the economy,society and environment in China's deserts.

关键词： Desert Windbreak and sand fixation road construction

PERTURBATION SOLUTION FOR THERMAL EXPANSION BUCKLING OF NO EXPANSION JOINT SLOPE PAVEMENT PLATE

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Applied Mathematics and Mechanics(English Edition) 1993年第3期14卷 277-284页

作者：陈建康王汝鹏 Jiangsu Agricultural College YangzhouShanghai College of Architectural and Municipal Engineering Shanghai

The mechanical mechanism of thermal expansion buckling of no expansion joint slope pavement undergoing the action of a temperature field was analyzed. By using the regular perturbation method, the formula of perturbation solution for this problem was derived, the relationship between critical laying temperature difference of slope pavement and of level straight pavement was studied, and the unified solution as well as its numerical results was also obtained. In terms of this research, the reasonable laying temperature of no expansion joint slope pavement was given.

关键词： Buckling Failure (mechanical) Perturbation techniques Plates (structural components) road construction Thermal expansion

Traffic organization during urban road constructions

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Journal of Beijing Institute of Technology 2012年第2期21卷 216-221页

作者：宋丽英 School of Traffic and Transportation Beijing Jiaotong University

This research presented a bi-level programming approach to optimize the schedule of ur- ban road construction activities based on a hypothetical transport network, with an objective of mini- mizing the overall traffic delays. A heuristic algorithm was utilized to identify a set of road construction schedules, while PARAMICS was adopted to estimate the total travel time in the network under each road construction scenario. To test the performance of proposed heuristics-simulation methodology, a numerical test was implemented. The overall results suggested that the proposed methodol- ogy could quickly find the optimum solution with good convergence.

关键词： artificial intelligence microscopic traffic simulation road construction road network