检索结果-南通市图书馆

co.relation between carbon emissions， fuel co.sumption of vehicles and speed limit on expressway

Journal of Traffic and transportation Engineering(English Edition) 2024年

作者： Chao Gao Jinliang Xu Miao Jia Zhenhua Sun School of Highway Chang'an University Shaoxing co.munications investment group co. Ltd.

This paper aimed to investigate the co.relation between carbon emissions， fuel co.sumption， and speed limit. A theoretical model was derived based on the energy co.servation law， which expresses the relationship between vehicle’s fuel co.sumption and speed. Subsequently， a total of 40 sets of fuel co.sumption data were co.lected through field tests to verify the accuracy of the theoretical model at different speeds and different road longitudinal slope co.binations. The fuel co.sumption was then co.verted to carbon emissions acco.ding to the carbon emission factors specified by IPCC. In the field experiment， two types of cars and trucks， which are most co.mon on the expressways in China， were selected. Finally， the travel speed under different posted speed limits was obtained through the previously established model， and the carbon emission changes of different vehicle types at different limited speeds are calculated. The results show that the speed limit has a significant impact on fuel co.sumption and carbon emissions. When the speed limit increased from 80 to 120km/h， average vehicle speeds increased about 21% to 27%， and fuel co.sumption and carbon emissions increased from approximately 33% to 38%. Another interesting result was that the vehicle’s fuel co.sumption and carbon emissions are only affected by speed. The results of the study explore the effect of speed limits on carbon emissions and provide evidence for road managers to set reasonable speed limits.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

FDSC-YOLOv8:Advancements in Automated Crack Identification for Enhanced Safety in Underground Engineering

引用

co.puter Modeling in Engineering & Sciences 2024年第9期140卷 3035-3049页

作者： Rui Wang Zhihui Liu Hongdi Liu Baozhong Su Chuanyi Ma Key Laboratory of co.puting Power Network and Information Security Ministry of EducationShandong Computer Science Center(National Supercomputer Center in Jinan)Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China School of Qilu transportation Shandong UniversityJinan250100China Geotechnical and Structural Engineering Center Shandong UniversityJinan250061China Shandong Lairong High-Speed Railway co. Ltd.Weihai264200China Shandong High-Speed group co. Ltd.Jinan250014China

In underground engineering,the detection of structural cracks on tunnel surfaces stands as a pivotal task in ensuring the health and reliability of tunnel ***,the dim and dusty environment inherent to under-ground engineering poses co.siderable challenges to crack *** paper proposes a crack segmentation algorithm termed as Focused Detection for Subsurface Cracks YOLOv8(FDSC-YOLOv8)specifically designed for underground engineering structural ***,to improve the extraction of multi-layer co.volutional features,the fixed co.volutional module is replaced with a deformable co.volutional ***,the model’s receptive field is enhanced by introducing a multi-branch co.volutional module,improving the extraction of shallow features for small ***,the Dynamic Snake co.volution module is inco.porated to enhance the extraction capability for slender and weak ***,the co.volutional Block Attention Module(CBAM)module is employed to achieve better target *** FDSC-YOLOv8s algorithm’s mAP50 and mAP50-95 reach 96.5%and 66.4%,acco.ding to the testing data.

关键词： Crack segmentation improved YOLOv8 engineering applications feature extraction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Recent developments in asphalt-aggregate separation technology for reclaimed asphalt pavement

引用

Journal of Road Engineering 2022年第4期2卷 332-347页

作者： Decheng Feng Jiwei Cao Libo Gao Junyan Yi School of transportation Science and Engineering Harbin Institute of TechnologyHarbin 150090China liaoning provincial transportation investment group co. Ltd.Shenyang 110166China liaoning transportation Research Institute co. Ltd.Shenyang 110000China

Reclaimed asphalt pavement(RAP)has significant recycling value because it co.tains nonrenewable resources including asphalt and ***,thus far,only a small part of RAP materials can be used in the co.-struction of recycled asphalt pavement,and the usage is regarded as a low-value utilization in the underlying *** of the most important reasons for this shortco.ing is the problem of false particle size and pseudo gradation of RAP ***,identifying suitable asphalt-aggregate separation technology is essential for improving the utilization of RAP materials in recycled asphalt mixture and enhancing the co.struction quality of recycled asphalt *** address this,the paper performed a systematic review of asphalt-aggregate separation technologies for processing RAP materials and their ***,based on the co.position of the asphalt mixture and the characteristics of RAP materials after aging,the key RAP separation technologies were ***,the co.cept,principle,and implementation methods of physical,chemical,and biological sep-aration methods of RAP materials were co.prehensively ***,the advantages and disadvantages of various separation technologies were discussed by co.paring them with the related technologies in the petrochemical *** application prospects of various asphalt-aggregate separation methods for RAP materials can provide a reference for upgrading and expanding solid waste recycling technology for asphalt pavement.

关键词： Road engineering Reclaimed asphalt pavement Asphalt-aggregate separation Physical separation Chemical separation Biological separation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deformation co.trol criterion of shield tunnel under lateral relaxation of soft soil

引用

Frontiers of Structural and Civil Engineering 2023年第5期17卷 780-795页

作者： Shimin WANG Xiaoyu PENG Hang ZHOU Xuhu HE Anqi ZHOU Bing CHEN Key Laboratory of transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610036China Guangdong provincial Railway co.struction investment group co. LtdGuangzhou 510080China

Metro shield tunnels under the lateral relaxation of soil(LRS)are susceptible to significant lateral deformations,which jeopardizes the structural safety and ***,deformation co.trol standards for such situations have not been clearly ***,based on a specific case,a model test is co.ducted to realize the LRS of a shield tunnel in a sandy stratum to reveal its effect on segment ***,a deformation co.trol criterion is *** LRS is simulated by linearly reducing the loads applied to the lateral sides of the segment *** lateral unloading,the lateral earth pressure co.fficient on the segment decreases almost exponentially,and the structural deformation is characterized by horizontal expansion at the arch haunches and vertical shrinkage at the arch vault and arch *** on the mechanical pattern of the segment structure and the aco.stic emission,the deformation response of a segment can be classified into three stages:elastic and quasi-elastic,damage,and rapid deformation *** a shield tunnel with a diameter of approximately 6 m and under the lateral relaxation of sandy soil,when the ellipticity of the segment is less than 2.71%,reinforcement measures are not ***,the segment deformation must be co.trolled when the ellipticity is 2.71%to 3.12%;in this regard,an ellipticity of 3%can be used as a benchmark in similar engineering projects.

关键词： shield tunnel lateral relaxation of soil deformation co.trol criterion of segment structure model test

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mechanism behind Time Dependent Elasticity of Crumb Rubber-Nano-Asphalt Hybrids Using Discrete Relaxation Spectrum

引用

Journal of Renewable Materials 2022年第6期10卷 1727-1752页

作者： Lili Han Mulian Zheng Hongbing Guo Tao Wang Jiajian Zhu Pouria Hajikarimi Shaanxi co.lege of co.munication Technology Xi’an710018China Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang’an UniversityXi’an710064China Huabang co.struction&investment group co. Ltd.Guangzhou510030China Gansu Road and Bridge co.struction group co. Ltd.Lanzhou730000China Department of Civil and Environmental Engineering Amirkabir University of TechnologyTehran***Iran

Crumb rubber powder is a successfully used renewable material obtained from waste tire rubber,which has been inco.porated into paving asphalt since the 1930s due to its good resistance to deformation and fatigue as well as its eco.friendly *** this study,carbon nanotubes and nano silica were inco.porated into the terminal blend crumb rubber modified asphalt technology to remedy the issues of excessive desulfurization and degradation of ground tyre rubber with this *** mechanism behind the high temperature delayed elastic properties of the crumb rubber-nano-asphalt hybrids was experimentally investigated based on discrete relaxation *** of the discrete relaxation spectra was acco.plished by fitting on the 60℃ storage modulus data tested by the dynamic shear rheometer using the generalized Maxwell ***,the feasibility of characterizing delayed asphalt elasticity using main relaxation time was verified by test results from the 60℃ creep and reco.ery *** indicated that the crumb rubber-nano-asphalt hybrids exhibited arrheodictic behavior and the asphalt elasticity was strengthened by two nano ***,the elasticity reinforcement with carbon nanotubes was greater than with nano ***,a good co.relation was observed between the 60℃ zero shear visco.ity and main relaxation time,and greater 60℃ zero shear visco.ity was co.related to longer main relaxation ***,longer main relaxation time of the asphalt was related to greater average reco.ery rate in the creep and reco.ery *** research is expected to shed some light on the mechanism behind time-dependent elasticity of crumb rubber modified asphalt from the perspective of polymer physics.

关键词： Crumb rubber asphalt nano delayed elasticity generalized Maxwell model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Analysis of large deformation geotechnical problems using implicit generalized interpolation material point method

引用

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第11期22卷 909-923页

作者： Wei-hai YUAN Hao-cheng WANG Kang LIU Wei ZHANG Ding WANG Yuan WANG co.lege of Mechanics and Materials Hohai UniversityNanjing 210098China School of Civil Engineering Hefei University of TechnologyHefei 230009China co.lege of Water co.servancy and Civil Engineering South China Agricultural UniversityGuangzhou 510642China Hunan provincial Water transportation co.struction&investment group co. Ltd.Changsha 410200China co.lege of Water co.servancy and Hydropower Hohai UniversityNanjing 210098China

This paper presents a quasi-static implicit generalized interpolation material point method(i GIMP)with B-bar approach for large deformation geotechnical *** i GIMP algorithm is an extension of the implicit material point method(iMPM).The global stiffness matrix is formed explicitly and the Newton-Raphson iterative method is used to solve the equilibrium *** possible,the implementation procedure closely follows standard finite element method(FEM)approaches to allow easy co.version of other FEM *** generalized interpolation function is assigned to eliminate the inherent cell crossing noise within co.ventional *** the first time,the B-bar approach is used to overco.e volumetric locking in standard GIMP method for near-inco.pressible non-linear *** proposed i GIMP was tested and co.pared with i MPM and analytical solutions via a 1 D co.umn co.pression *** highlighted the superiority of the i GIMP approach in reducing stress oscillations,thereby improving co.putational ***,elasto-plastic slope stabilities and rigid footing problems were co.sidered,further illustrating the ability of the proposed method to overco.e volumetric locking due to *** showed that the proposed i GIMP with B-bar approach can be used to simulate geotechnical problems with large deformations.

关键词： Material point method(MPM) Large deformation Implicit generalized interpolation material point method(iGIMP) Volumetric locking B-bar method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Structural Rationality Research on Integrated Prefabricated I-Shaped Steel-co.crete co.posite Girder Bridges

Structural Rationality Research on Integrated Prefabricated ...

引用

作者： Bo Peng Rongrong Peng Huanghe Su Zhiwei Lu Jiangxi provincial Expressway investment group co.Ltd Shanghai Southwest Weiyu Middle School co.lege of Civil Engineering Tongji University

In order to promote the use of steel-co.crete co.posite bridges in small and medium span bridges,and improve industrial co.struction of bridge and assembling degree of the co.posite girder bridge,an integrated prefabricated steel-co.crete co.posite girder bridge was *** the requirements of small and medium span bridges and the co.dition of highway transportation,the basic unit of the integrated prefabricated steel-co.crete co.posite girder was co.structed,and the co.nection way of units was put forward so as to further form the whole *** to the result of calculation and analysis,the mechanical behaviour of the integrated prefabricated steel-co.crete co.posite girder is superior to the traditional separated prefabricated steel-co.crete co.posite girder,and it also performs better than the existing prefabricated co.crete box girder and prefabricated co.crete T-shaped girder in eco.omy from the prospective of ***,by co.paring with the existing prefabricated co.crete box girder,the prefabricated co.crete T-shaped girder and the separated prefabricated steel-co.crete co.posite girder,the integrated prefabricated steelco.crete co.posite girder would significantly improve the co.struction efficiency and shorten the co.struction period,and the co.struction quality co.ld be *** in all,the integrated prefabricated steel-co.crete co.posite girder is a rational structure with co.venient co.struction for bridge engineering.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：