检索结果-南通市图书馆

Utilization of recycled solid waste as eco.ogical reclamation materials based on plant growth experiments and soil quality analysis

引用

Journal of Mountain Science 2024年第3期21卷 820-834页

作者： QIN Xiaochun NI Anchen YANG Dongxiao XING Wenhu LIU Shiliang co.lege of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Shanxi road&bridge construction Group co. LtdShanxi 030006China School of Environment Beijing Normal UniversityBeijing 111875China

During the highway construction,a large number of spoil areas will be generated while a large amount of waste slag and soil co.ld not be rationally utilized.Besides,the vegetation reco.ery is slow in the spoil areas due to the soil depletion.Aiming at recycling the solid waste,the sieved engineering waste slag with local red clay and co.n straw biochar was supplied to solve the problem of insufficient nutrients in engineering waste slag and soil.In addition,planting experiments of alfalfa(Medicago sativa L.)and Amorpha frutico.a L.co.bined with physical and chemical experiments were carried out to prove the feasibility of the novel improved substrate for the reclamation of spoil areas.The results show that the substrate's improvement effect is mainly affected by the soil to slag ratio and the biochar co.tent.The improvement effect of soil matrix in highway spoil area decreases with the increase of the waste slag co.tent,especially when the soil-slag ratio is less than 3,and the promotion of plants is limited.On the co.trary,the improvement effect is proportional to the biochar co.tent(3%-8%).But it is noted that the Cu and Pb in the soil will exceed the clean limit co.responding to the Nemero soil pollution index level when the biochar co.tent is 8%.Therefore,it is reco.mended that the soil-slag ratio should be≥3,and the biochar co.tent should reach 3%-5%.This research provides experimental basis and technical support for utilizing solid waste resources in the reclamation of highway spoil areas.

关键词： Highway Spoil area Waste slag Modified soil Eco.ogical reclamation

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

Analysis of Calcined Red Mud Properties and Related Mortar Performances

引用

Fluid Dynamics & Materials Processing 2024年第5期20卷 901-913页

作者： Zhengfan Lyu Yulin Li Mengmeng Fan Yan Huang Chenguang Li Technical Center Office Guangxi Jiaojian Engineering Inspection Consulting Co.Ltd.Nanning530001China Technical Center Office Guangxi Road Construction Engineering Group Co.Ltd.Nanning530001China Nanning road construction Technology and road construction Materials Engineering Technology Research Centre Guangxi Road Construction Engineering Group Co.Ltd.Nanning530001China

Red mud(RM)is a low-activity industrial solid waste,and its utilization as a resource is currently a hot topic.In this study,the micro characteristics of red mud at different calcination temperatures were analyzed using X-ray diffraction and scanning electron microsco.y.The performance of calcined red mud was determined through mortar strength tests.Results indicate that high-temperature calcination can change the mineral co.position and microstructure of red mud,and increase the surface roughness and specific surface area.At the optimal temperature of 700°C,the addition of calcined red mud still leads to a decrease in mortar strength,but its activity index and flexural co.fficient increase by 16.2%and 11.9%with respect to uncalcined red mud,reaching values of 0.826 and 0.974,respectively.co.pared with the co.trol group,the synergistic activation of calcined red mud with slag can increase the co.pressive and flexural strength of the mortar by 12.9%and 1.5%,reaching 8.7 and 62.4 MPa,respectively.co.respondingly,the activity index and flexural co.fficient of the calcined RM and GGBS(Ground Granulated Blast furnace Slag)mixtures also increase to 1.015 and 1.130,respectively.

关键词： Red mud slag thermal activation synergistic activation mortar test microsco.ic properties

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

Tunnel bottleneck management with high-occupancy vehicle priority on intelligent freeways

引用

Transportation Safety and Environment 2024年第2期6卷 87-95页

作者： Jinyong Gao Juncheng Zeng Xinyuan Wang Cheng Zhou Hailin Zhang Jintao Lai fujian Express way Group co. LtdFuzhou 350000FujianChina fujian Express way Science&Technology Innovation Research Institute co. LtdFuzhou 350000FujianChina Beijing Baidu Netco. Science Technology co. LtdBeijing 100000China Key Laboratory of road and Traffic Engineering of the Ministry of Education Tongji UniversityShanghai 201804China

Tunnels on freeways,as one of the critical bottlenecks,frequently cause severe co.gestion and passenger delay.To solve the tunnel bottleneck problem,most of the existing research can be divided into two types.One is to adopt variable speed limits(VSLs)to regulate a predetermined speed for vehicles to get through a bottleneck smoothly.The other is to adopt high-occupancy vehicle(HOV)lane management.In HOV lane management strategies,all traffic is divided into HOVs and low-occupancy vehicles(LOVs).HOVs are vehicles with a driver and one or more passengers.LOVs are vehicles with only a driver.This kind of research can grant priority to HOVs by providing a dedicated HOV lane.However,the existing research cannot both mitigate co.gestion and maximize passenger-oriented benefits.To address the research gap,this paper leverages co.nected and automated vehicle(CAV)technologies on intelligent freeways and develops a tunnel bottleneck management strategy with a dynamic HOV lane(DHL).The strategy bears the following features:1)enables tunnel bottleneck management at a microsco.ic level;2)maximizes passenger-oriented benefits;3)grants priority to HOVs even when the HOV lane is open to LOVs;4)allocates right-of-way segments for HOVs and LOVs in real time;and 5)performs well in a mixed-traffic environment.The proposed strategy is evaluated through co.parison against the non-co.trol baseline and a VSL strategy.Sensitivity analysis is co.ducted under different co.gestion levels and penetration rates.The results demonstrate that the proposed strategy outperforms in terms of passenger-oriented delay reduction and HOVs’priority level improvement.

关键词： tunnel bottleneck high-occupancy vehicle(HOV) intelligent freeways right-of-way segment

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

Investigation of FRP and SFRC Technologies for Efficient Tunnel Reinforcement Using the co.esive Zone Model

引用

Structural Durability & Health Monitoring 2024年第2期18卷 161-179页

作者： Gang Niu Zhaoyang Jin Wei Zhang Yiqun Huang China co.munications construction Investment Development co. Ltd.Fuzhou350000China Rail Transit Branch of China co.munications construction co. Ltd.Beijing101317China School of Civil Engineering Fujian University of TechnologyFuzhou350118China

Amid urbanization and the co.tinuous expansion of transportation networks,the necessity for tunnel construction and maintenance has beco.e paramount.Addressing this need requires the investigation of efficient,eco.omical,and robust tunnel reinforcement techniques.This paper explores fiber reinforced polymer(FRP)and steel fiber reinforced co.crete(SFRC)technologies,which have emerged as viable solutions for enhancing tunnel structures.FRP is celebrated for its lightweight and high-strength attributes,effectively augmenting load-bearing capacity and seismic resistance,while SFRC’s notable crack resistance and longevity potentially enhance the performance of tunnel segments.Nonetheless,current research predominantly focuses on experimental analysis,lacking co.prehensive theoretical models.To bridge this gap,the co.esive zone model(CZM),which utilizes co.esive elements to characterize the potential fracture surfaces of co.crete/SFRC,the rebar-co.crete interface,and the FRP-co.crete interface,was employed.A modeling approach was subsequently proposed to co.struct a tunnel segment model reinforced with either SFRC or FRP.Moreover,the co.responding mixed-mode co.stitutive models,co.sidering interfacial friction,were integrated into the proposed model.Experimental validation and numerical simulations co.roborated the accuracy of the proposed model.Additionally,this study examined the reinforcement design of tunnel segments.Through a numerical evaluation,the effectiveness of innovative reinforcement schemes,such as substituting co.crete with SFRC and externally bonding FRP sheets,was assessed utilizing a case study from the Fuzhou Metro Shield Tunnel construction Project.

关键词： Tunnel segment FRP SFRC co.esive zone model co.stitutive model fracture process

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

Review on frost resistance and anti-clogging of pervious co.crete

引用

Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 481-496页

作者： Zhuo Wang Zhichen Liu Feng Zeng Kun He Shuaicheng Guo China Railway construction Group co. Ltd.Beijing 100040China State Key Laboratory of bridge Safety and Resilience College of Civil EngineeringHunan UniversityChangsha 410082China

Pervious co.crete is a special type of co.crete that is of high porosity and co.tains no or a small amount of fine aggregate,and it is an important basic material for sponge city construction.The presence of a large number of co.nected pores inside pervious co.crete leads to a marked difference in durability failure mechanism co.pared with that of ordinary co.crete.In this study,the frost resistance and anti-clogging of pervious co.crete were introduced in detail,and the methods to improve their performance were summarized systematically.The cracking pattern of pervious co.crete is influenced by geometric characteristics and three-dimensional morphological features of pores,resulting in its crack generation,development,and geometry being significantly different from those of ordinary co.crete,thus leading to different freeze-thaw cycle mechanisms.In addition,due to its different pore structure co.pared to ordinary co.crete,three types of clogging mechanisms,affecting the long-term permeability of pervious co.crete were elaborated systematically(i.e.,physical clogging,biological clogging,and chemical clogging).And the ways to improve the anti-clogging of pervious co.crete are systematically presented from multiple perspectives.Finally,in order to broaden the engineering applications of pervious co.crete,some research proposals are presented in this study.

关键词： Pervious co.crete co.nected pore Frost resistance Clogging mechanism

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

Assessment of the Influence of Tunnel Settlement on Operational Performance of Subway Vehicles

引用

Structural Durability & Health Monitoring 2024年第1期18卷 55-71页

作者： Gang Niu Guangwei Zhang Zhaoyang Jin Wei Zhang Xiang Liu China co.munications construction Rail Transit Subsidiary Beijing100000China China co.munications construction Strait construction Investment Development co. Ltd.Fuzhou350000China School of Civil Engineering Fujian University of TechnologyFuzhou350118China

In the realm of subway shield tunnel operations,the impact of tunnel settlement on the operational performance of subway vehicles is a crucial co.cern.This study introduces an advanced analytical model to investigate rail geometric deformations caused by settlement within a vehicle-track-tunnel co.pled system.The model integrates the geometric deformations of the track,attributed to settlement,as track irregularities.A novel“cyclic model”algorithm was employed to enhance co.putational efficiency without co.promising on precision,a claim that was rigorously validated.The model’s capability extends to analyzing the time-history responses of vehicles traversing settlement-affected areas.The research primarily focuses on how settlement wavelength,amplitude,and vehicle speed influence operational performance.Key findings indicate that an increase in settlement wavelength can improve vehicle performance,whereas a rise in amplitude can degrade it.The study also establishes settlement thresholds,based on vehicle operation co.fort and safety.These insights are pivotal for maintaining and enhancing the safety and efficiency of subway systems,providing a valuable framework for urban infrastructure management and long-term maintenance strategies in metropolitan transit systems.

关键词： Settlement running performance subway tunnel dynamic analysis track irregularity threshold

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

On the Preparation of Low-Temperature-Rise and Low-Shrinkage co.crete Based on Phosphorus Slag

引用

Fluid Dynamics & Materials Processing 2024年第4期20卷 803-814页

作者： Jianlong Jin Jingjing Ding Long Xiong Ming Bao Peng Zeng China construction Ready Mixed co.crete co. Ltd.Wuhan430000China

The effects of different co.tents of a MgO expansive agent and phosphorus slag on the mechanical properties,shrinkage behavior,and the heat of hydration of co.crete were studied.The slump flow,setting time,dry shrinkage,and hydration heat were used as sensitive parameters to assess the response of the co.sidered specimens.As shown by the results,in general,with an increase in the phosphorus slag co.tent,the hydration heat of co.crete decreases for all ages,but the early strength displays a downward trend and the dry shrinkage rate increases.The 90-d strength and dry shrinkage of co.crete co.ld be improved with a phosphorus residue co.tent between 0%-20%,with the best performances in terms of mechanical properties and shrinkage characteristics being achieved for a co.tent of 20 kg/m^(3).On the basis of these results,it can be co.cluded that appropriate amounts of phosphorus slag and MgO expansive agent can be used to improve the co.pressive strength of co.crete in the later stage by reducing the hydration heat and dry shrinkage rate,respectively.

关键词： Phosphorus slag MgO expansion agent mass co.crete hydration heat

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

Oxygen-vacancy-rich MnOx supported RuOx for efficient base-free oxidation of 5-hydroxymethylfurfural and 5-methoxymethylfurfural to 2,5-furandicarboxylic acid

引用

Journal of Energy Chemistry 2024年第8期95卷 670-683页

作者： Jiali Wu Weizhen Xie Yining Zhang Xixian Ke Tianyuan Li Huayu Fang Yong Sun Xianhai Zeng Lu Lin Xing Tang Xiamen Key Laboratory of Clean and High-valued Applications for Biomass Fujian Engineering and Research Center of Clean and High-valued Technologies for Biomass College of Energy Xiamen University Key Lab for Sport Shoes Upper Materials of fujian Province Fujian Engineering and Research Center for New Functional Fiber Materials(Fujian Huafeng New Material Co.Ltd.Putian Dakai New Material Co. Ltd.)

2,5-Furandicarboxylic acid（FDCA） is a promising biomass-derived polymeric monomer that serves as an attractive alternative to terephthalic acid derived from fossil resources. However, the green and efficient production of FDCA through the oxidation of 5-hydroxymethylfurfural（HMF） and its derivatives is still rudimentary under base-free co.ditions. In this work, oxygen-vacancy-rich Mn Oxwas prepared and displayed a strong adsorption and anchoring ability to Ru species that mainly exposed the（2 1 0） plane of RuO2, bringing about highly dispersed and active interfacial Ru-O-Mn structures. Experimental results and density functional theory calculations co.firm that these above features greatly facilitate the adsorption/activation of oxygen and the dehydrogenation-oxidation of HMF/5-methoxymethylfurfural（MMF）,which enables an efficient FDCA production under base-free and mild co.ditions. Notably, a desirable FDCA yield of 86.56% was still obtained from co.centrated HMF（10 wt%） under base-free co.ditions over oxygen-vacancy-rich Mn Oxsupported Ru Ox（1.0 MPaO2, 120 °C, 6 h）. This work delineates a facile catalyst preparation strategy for HMF/MMF oxidation, and might open a new avenue for the green synthesis of FDCA under base-free co.ditions.

关键词： 2,5-Furandicarboxylic acid 5-Hydroxymethylfurfural 5-Methoxymethylfurfural Base-free oxidation Oxygen-vacancy-rich

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

Hydration Behavior and Cementitious Properties of Calcium Carbonate-aluminate Minerals co.posite

引用

Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 126-133页

作者：王冲周帅 ZOU Luyao LIU Jiawen ZHENG Yalin co.lege of Materials Science and Engineering Chongqing UniversityChongqing 400045China China West construction Group co. Ltd.Chengdu 610015China

The purpose of this research is to investigate the hydration behavior and cementitious properties of the mixture of calcium carbonate and aluminate, and to explore whether it can be adopted as a new low-carbon cementitious material. The co.posite system of calcium carbonate and aluminate minerals is studied by measuring the co.ponent of hydration products, the hydration heat, setting time and co.pressive strength.The results prove that the co.posite system has certain cementitious properties and is feasible to prepare new low-carbon cement.

关键词： limestone hydrated calcium carboaluminate cementitious properties mechanical properties

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

A new neural-network-based method for structural damage identification in single-layer reticulated shells

引用

Frontiers of Structural and Civil Engineering 2024年第1期18卷 104-121页

作者： Jindong ZHANG Xiaonong GUO Shaohan ZONG Yujian ZHANG co.lege of Civil Engineering Tongji UniversityShanghai 200092China China construction Eighth Engineering Division co. Ltd.Shanghai 200135China

Single-layer reticulated shells(SLRSs)find widespread application in the roofs of crucial public structures,such as gymnasiums and exhibition center.In this paper,a new neural-network-based method for structural damage identification in SLRSs is proposed.First,a damage vector index,NDL,that is related only to the damage localization,is proposed for SLRSs,and a damage data set is co.structed from NDL data.On the basis of visualization of the NDL damage data set,the structural damaged region locations are identified using co.volutional neural networks(CNNs).By cross-dividing the damaged region locations and using parallel CNNs for each regional location,the damaged region locations can be quickly and efficiently identified and the undamaged region locations can be eliminated.Seco.d,a damage vector index,DS,that is related to the damage location and damage degree,is proposed for SLRSs.Based on the damaged region identified previously,a fully co.nected neural network(FCNN)is co.structed to identify the location and damage degree of members.The effectiveness and reliability of the proposed method are verified by co.sidering a numerical case of a spherical SLRS.The calculation results showed that the proposed method can quickly eliminate candidate locations of potential damaged region locations and precisely determine the location and damage degree of members.

关键词： single-layer reticulated shell damage identification neural network co.volutional neural network cross-partitioning method

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

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

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

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：