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Preparation of temperature-controlled salt storage materials and application in ultra-thin friction course

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

作者： Yixue Shang Peng Guo Junfeng Gao Yunxia Feng Yuhong Luo Yuanzhao Chen Yang Liu Feng Wang National and Local Joint engineering Research Center of transportation and civil engineering Materials， Chongqing Jiaotong University School of civil engineering and transportation， North China University of Water Resources and Electric Power transportation Comprehensive Administrative Law Enforcement Detachment，Chizhou transportation Bureau China Merchants Chongqing Highway engineering Testing Center Co.，Ltd.

Salt-storage anti-icing ultra-thin friction courses （SAUTFC） are an effective preventive maintenance treatment to improve road performance and ensure the safety of winter pavement traffic. However， the addition of salt storage agents and precipitates decreases the engineering and anti-icing performance. Hence， this study used the temperature-controlled salt-controlled-release deicer （SCD） to prepare and characterize SAUTFC. The microstructure and properties of SCD were investigated. The SAUTFC preparation procedures and content of SCD were determined. Subsequently， the interlayer bonding properties， skid resistance performance， and anti-freeze properties were evaluated. The results indicated that SCD with a glass transition temperature of 0.2 °C can control the precipitation of salts before the winter. The SCD dosing in SAUTFC is 75% of the replacement mineral powder， and interlayer shear strength reaches its maximum when the application rate of the tack coat is 1 kg/m2. The wear resistance of SAUTFC was investigated by accelerated loading tests， which showed that SAUTFC still provides excellent skid resistance after four years. In addition， the SAUTFC accelerates the melting rate of snow and ice and decreases the bonding force between ice and the specimen surface， with excellent anti-freeze durability. Therefore， the application of salt storage materials in ultra-thin friction courses to provide active snow and ice removal on winter pavements is feasible.

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Urban Flood Mitigation Strategies with Coupled Gray–Green Measures: A Case Study in Guangzhou City, China

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International Journal of Disaster Risk Science 2024年第3期15卷 467-479页

作者： Jiayue Li Jiajun Zeng Guoru Huang Wenjie Chen School of civil engineering and transportation South China University of Technology School of Architecture South China University of Technology State Key Laboratory of Subtropical Building and Urban Science South China University of Technology College of Water Conservancy and civil engineering South China Agricultural University

The integration of gray and green infrastructure has proven to be a feasible approach for managing stormwater in established urban areas. However, evaluating the specific contributions of such coupled strategies is challenging. This study introduced a novel integrated hydrological-hydrodynamic model that takes into account the layout of low-impact development(LID)facilities along with pipeline alignment and rehabilitation. Reliable results from modeling were used to assess the individual contribution of LID and improved drainage facilities to urban flooding mitigation. We selected a natural island in Guangzhou City, China, as the study site. The results indicate that combining three LID measures, namely green roofs, sunken green spaces, and permeable pavements, can reduce total runoff by 41.7% to 25.89% for rainfall recurrence periods ranging from 1year to 100 years, and decrease the volume of nodal overflow by nearly half during rainfall events of less than 10-year return period. By integrating LID measures with the upgraded gray infrastructure, the regional pipeline overloading condition is substantially alleviated, resulting in a significant improvement in pipeline system resilience. For urban flooding control, it is recommended to integrate sufficient green space and avoid pipe-laying structural issues during urban planning and construction. The findings may assist stakeholders in developing strategies to best utilize gray and green infrastructure in mitigating the negative eff ects of urban flooding.

关键词： Coupled hydrodynamic model Gray–green approach Guangzhou City LID Pipe renovation Urban inundation

Road sub-surface defect detection based on gprMax forward simulation-sample generation and Swin Transformer-YOLOX

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Frontiers of Structural and civil engineering 2024年第3期18卷 334-349页

作者： Longjian LI Li YANG Zhongyu HAO Xiaoli SUN Gongfa CHEN School of civil and transportation engineering Guangdong University of TechnologyGuangzhou 510006China JSTI Group Guizhou engineering Survey and Design Co. Ltd.Guangzhou 510800China Guangzhou Municipal engineering Testing Co. Ltd.Guangzhou 510520China

Training samples for deep learning networks are typically obtained through various field experiments,which require significant manpower,resource and time ***,it is possible to utilize simulated data to augment the training *** this paper,by comparing the actual experimental model with the simulated model generated by the gprMax[1]forward simulation method,the feasibility of obtaining simulated samples through gprMax simulation is ***,the samples generated by gprMax forward simulation are used for training the network to detect objects in existing real *** the same time,aiming at the detection and intelligent recognition of road sub-surface defects,the Swin-YOLOX algorithm is introduced,and the excellence of the detection network,which is improved by augmenting the simulated samples with real samples,is further *** comparing the prediction performance of the object detection models,it is observed that the model trained with mixed samples achieved a recall of 94.74%and a mean average precision(maP)of 97.71%,surpassing the model trained only on real samples by 12.95%and 15.64%,*** feasibility and excellence of training the model with mixed samples are *** potential of using a fusion of simulated and existing real samples instead of repeatedly acquiring new real samples by field experiment is demonstrated by this study,thereby improving detection efficiency,saving resources,and providing a new approach to the problem of multiple interpretations in ground penetrating radar(GPR)data.

关键词： ground penetrating radar gprMax forward modeling sample generation Swin-YOLOX object detection

A novel tunnel waterproof-drainage system based on double-bonded waterproofing materials and its seepage characteristics

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Frontiers of Structural and civil engineering 2024年第9期18卷 1321-1336页

作者： Xiaohe SUN Chenghua SHI Guoqing XIAO Yangyang GE Chengyong CAO School of civil engineering Central South UniversityChangsha 410075China PowerChina ZhongNan engineering Corporation Limited Changsha 410014China State Key Laboratory of Special Functional Waterproof Materials Beijing Oriental Yuhong Waterproof Technology Co.Ltd.Beijing 101111China College of civil and transportation engineering Shenzhen UniversityShenzhen 518060China

Double-bonded spray membrane waterproofing materials have excellent waterproofing performance and can improve the load-bearing capacity of tunnel linings,leading to an increasing global ***,due to the double-bonded capability of spray membrane materials,traditional interlayer drainage methods cannot be *** limitation makes it difficult to use them in drainage-type tunnels,significantly restricting their range of *** this regard,a novel tunnel waterproof-drainage system based on double-bonded spray membrane materials was proposed in this *** proposed drainage system primarily comprises upper drainage sheets and bottom drainage blind pipes,both located in the tunnel circumferential direction,as well as longitudinal drainage pipes within the ***,numerical calculation methods are employed to analyze the seepage characteristics of this system,revealing the water pressure distribution around the *** results indicate that in the novel waterproof-drainage system,the water pressure in the secondary lining exhibits a“mushroom-shaped”distribution in the circumferential direction,while the water pressure in the longitudinal direction exhibits a“wave-like”***,comparative results with other waterproof-drainage systems indicate that under typical working conditions with a water head of 160 m and a rock permeability coefficient of 10^(−6)m/s,the maximum water pressure in the secondary lining of the novel waterproof-drainage system is 0.6 *** represents a significant reduction compared to fully encapsulated waterproofing and traditional drainage systems,which respectively reduce the water pressure by 65%and 30%.The applicability analysis of the double-bonded waterproofing and drainage system reveals that it can reduce at least 40%of the static water pressure in any groundwater *** novel drainage system provides a valuable reference for the application of double-bonded spray membr

关键词： tunnel drainage spray-applied waterproofing membrane numerical simulation water pressure

Influence of cutterhead opening ratio on soil arching effect and face stability during tunnelling through non-uniform soils

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Underground Space 2024年第4期17卷 45-59页

作者： Xue-Jian Chen Pei-Pei Fang Qiu-Nan Chen Jun Hu Kai Yao Yong Liu State Key Laboratory of Water Resources engineering and Management Wuhan UniversityWuhan 430072China Hubei Technology Innovation Center for Smart Hydropower Wuhan 430000China College of civil engineering Anhui Jianzhu UniversityHefei 230601China School of civil engineering Hunan University of Science and TechnologyXiangtan 411201China School of civil and Architectural engineering Hainan UniversityHaikou 570228China School of Qilu transportation Shandong UniversityJinan 250002China

Tunnelling has increasingly become an essential tool in the exploration of underground space.A typical construction problem is the face instability during tunnelling,posing a great threat to associated *** face instability often occurs with the soil arching *** study investigates the combined effect of cutterhead opening ratio and soil non-uniformity on soil arching effect and face stability,via conducting random finite-element analysis coupled with Monte–Carlo *** results underscore that the face stability is strongly associated with the evolution of stress *** obtained stability factors in the uniform soils can serve as a reference for the design of support pressure in practical tunnelling *** addition,non-uniform soils exhibit a lower stability factor than uniform soils,which implies that the latter likely yields an underestimated probability of face *** tunnel face is found to have a probability of failure more than 50%if the spatial non-uniformity of soil is *** the end,a practical framework is established to determine factor of safety(FOS)corresponding to different levels of probability of face failure considering various opening ratios in non-uniform *** required FOS is 1.70 to limit the probability of face instability no more than 0.1%.Our findings can facilitate the prediction of probability of instability in the conventionally deterministic design of face pressure.

关键词： Tunnel Face stability Soil arching effect Cutterhead opening ratio Non-uniform soil Random field

Challenges in Li-ion battery high-voltage technology and recent advances in high-voltage electrolytes

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Journal of Energy Chemistry 2024年第4期91卷 73-98页

作者： Jianguo Liu Baohui Li Jinghang Cao Xiao Xing Gan Cui Shandong Key Laboratory of Oil&Gas Storage and transportation Safety College of Pipeline and Civil EngineeringChina University of Petroleum(East China)Qingdao 266580ShandongChina

The electrolyte directly contacts the essential parts of a lithium-ion battery,and as a result,the electrochemical properties of the electrolyte have a significant impact on the voltage platform,charge discharge capacity,energy density,service life,and rate discharge *** raising the voltage at the charge/discharge plateau,the energy density of the battery is ***,this causes transition metal dissolution,irreversible phase changes of the cathode active material,and parasitic electrolyte oxidation *** article presents an overview of these concerns to provide a clear explanation of the issues involved in the development of electrolytes for high-voltage lithium-ion ***,solidstate electrolytes enable various applications and will likely have an impact on the development of batteries with high energy *** is necessary to improve the high-voltage performance of electrolytes by creating solvents with high thermal stabilities and high voltage resistance and additives with superior film forming performance,multifunctional capabilities,and stable lithium *** offer suggestions for the future development of high-energy lithium-ion batteries,we conclude by offering our own opinions and insights on the current development of lithium-ion batteries.

关键词： Lithium-ion battery High voltage Electrolyte additive Solid electrolyte

Construction of shallow buried large-span metro stations using the small pipe roof-beam method

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Frontiers of Structural and civil engineering 2024年第1期18卷 122-136页

作者： Qian BAI Wen ZHAO Yingda ZHANG Pengjiao JIA Xiangrui MENG Bo LU Xin WANG Dazeng SUN School of Resources and civil engineering Northeastern UniversityShenyang 110819China Centre for Infrastructure engineering and Safety School of Civil and Environmental EngineeringThe University of New South WalesNSW 2052Australia School of Rail transportation Soochow UniversitySuzhou 215131China China Northeast Architectural Design and Research Institute Co. Ltd.Shenyang 110006China

In relation to the Shifu Road Station project on Line 4 of the Shenyang Metro in China,a small-pipe roof-beam method for constructing subway stations is ***,a numerical simulation was performed to optimize the supporting parameters of the proposed method and determine the design ***,the deformation of the pipe roof and surface settlement during the construction process were ***,the surface settlement attributed to the excavation was studied through field monitoring,and the proposed method was compared with other *** results show that an increase in the pipe-roof spacing has little effect on the surface settlement and piperoof *** bearing capacity of the pipe roof can be efficiently utilized once the flexural stiffness reaches 2EI,and the flexural stiffness is not the dominant factor controlling the *** essential stages in controlling surface settlement are the excavations of the transverse pilot tunnels and the soil between *** final settlement value of the ground was 24.1 mm,resulting in a reduction in the construction period by at least five months while satisfying the control requirements.

关键词： subway station pipe-roof method surface settlement simulation on-site monitoring

A hybrid contact approach for modeling soil-structure interaction using the material point method

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Journal of Rock Mechanics and Geotechnical engineering 2024年第5期16卷 1864-1882页

作者： Qinyang Sang Yonglin Xiong Rongyue Zheng Xiaohua Bao Guanlin Ye Feng Zhang Key Laboratory of Impact and Safety engineering Ministry of EducationSchool of Mechanical Engineering and MechanicsNingbo UniversityNingbo315211China Institute of Geotechnical engineering Ningbo UniversityNingbo315211China College of civil and transportation engineering Shenzhen UniversityShenzhen518060China Department of civil engineering Shanghai Jiao Tong UniversityShanghai200240China Department of civil engineering Nagoya Institute of TechnologyShowa-kuGokiso-choNagoya466-8555Japan

The grid-based multi-velocity field technique has become increasingly popular for simulating the Material Point Method(MPM)in contact ***,this traditional technique has some shortcomings,such as(1)early contact and contact penetration can occur when the contact conditions are unsuitable,and(2)the method is not available for contact problems involving rigid-nonrigid materials,which can cause numerical *** study presents a new hybrid contact approach for the MPM to address these limitations to simulate the soil and structure *** approach combines the advantages of point-point and point-segment contacts to implement contact detection,satisfying the impenetrability condition and smoothing the corner contact *** proposed approach is first validated through a disk test on an inclined ***,several typical cases,such as granular collapse,bearing capacity,and deformation of a flexible retaining wall,are simulated to demonstrate the robustness of the proposed approach compared with FEM or analytical ***,the proposed method is used to simulate the impact of sand flow on a deformable *** results show that the proposed contact approach can well describe the phenomenon of soil-structure interaction problems.

关键词： Material point method Soil-structure interaction Numerical simulation Contact algorithm

Fatigue Resistance of RCA Modified Asphalt Based on Dielectric Properties

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 91-101页

作者：陆佳宝王国忠 HU Jiangsan LIU Zhongning College of Energy and transportation engineering Inner Mongolia Agricultural UniversityHohhot 010018China

In order to study the anti-fatigue performance of RCA modified asphalt (RMA),the performance of RMA and 90#matrix asphalt with different modifier content were measured by asphalt penetration,ductility,softening point,Brookfield viscosity,rheological index,infrared spectrum and dielectric constant *** paper discusses the changes of asphalt basic indexes,fatigue properties and asphalt components based on dielectric properties under different modifier contents,and analyzes the grey correlation degree between components and asphalt pavement performance *** results show that the optimum content of RCA modifier is 16.7%of the asphalt quality according to the penetration,ductility,softening point,Brockfield viscosity,viscosity temperature curve and fatigue *** the phase angle-strain curve,there is disorder in the latter part of the *** to the strain (ε_(d)) corresponding to the disorder point,a new fatigue failure criterion is proposed and *** on the new asphalt fatigue failure criterion,the fatigue prediction model of asphalt mixture is improved,and the fatigue life predicted by the improved fatigue model is compared with the fatigue life obtained by four-point bending fatigue *** results show that the proposed new asphalt fatigue failure criterion is reasonable,and the fatigue life predicted by the improved asphalt mixture fatigue prediction model is *** research method of classifying asphalt components based on dielectric properties is simple and effective,and the components have a high correlation with the road performance of base asphalt and modified asphalt.

关键词： dielectric properties anti-fatigue performance fatigue failure criterion RCA modified asphalt