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Full-Text Articles in Materials Science and Engineering

Multi‑Dimensional And Multi‑Point Random Seismic Response Analysis Of Long‑Span Cable‑Stayed Bridges At Different Sites, Shi Yi, Lu Lu, Fan Shuli, Shen Meng, Zuo Chunyuan, Sun Xinguo, Cao Feifei Oct 2024

Multi‑Dimensional And Multi‑Point Random Seismic Response Analysis Of Long‑Span Cable‑Stayed Bridges At Different Sites, Shi Yi, Lu Lu, Fan Shuli, Shen Meng, Zuo Chunyuan, Sun Xinguo, Cao Feifei

Journal of China & Foreign Highway

To study the random seismic response of long-span cable-stayed bridges at different sites,the site transfer function was used to evaluate the influence of different site conditions on ground motion propagation.By considering the traveling wave effect and the coherence effect,the multi-point power spectrum under different site conditions was generated.By using the pseudo excitation method for solving the absolute displacement,the seismic responses of cable-stayed bridges under uniform excitation and multi-dimensional and multi-point excitation at different sites were compared.A long-span cable-stayed bridge was selected as an example,and Ansys finite element software was used to analyze the random seismic response of the bridge.By considering …


Rigid Domain Optimization Of Steel Truss Joint With Reference To Multi‑Scale Model, Liu Gaocheng, Liu Jian, Dong Chuangwen, Li Chuanxi Oct 2024

Rigid Domain Optimization Of Steel Truss Joint With Reference To Multi‑Scale Model, Liu Gaocheng, Liu Jian, Dong Chuangwen, Li Chuanxi

Journal of China & Foreign Highway

The rigidity enhancement effect of the integral gusset plate is often simulated in the calculation of an integral nodal steel truss bridge by using a beam element with a rigid arm to improve the calculation accuracy.By taking Zhongshan Lianshwan Bridge as the engineering background,an optimization method based on a multi-scale truss model for nodal rigid domain simulation was proposed and verified.Five consecutive standard sections were selected as the study objects,and the beam element model with rigid arm and the multi-scale model of gusset plate substructure were established by using Ansys.The same boundary and loading conditions were applied.The deflection of the …


Impact Resistance Of Ecc Pipe Piles Based On Ls‑Dyna, Zeng Qingyou, Ye Chenfeng, Liu Junjun, Feng Kai, Cheng Peiyuan, Chen Weihong Oct 2024

Impact Resistance Of Ecc Pipe Piles Based On Ls‑Dyna, Zeng Qingyou, Ye Chenfeng, Liu Junjun, Feng Kai, Cheng Peiyuan, Chen Weihong

Journal of China & Foreign Highway

To study the impact resistance of Engineering Cementitious Composite (ECC) pipe piles,this paper used ANSYS/LS-DYNA to simulate the impact of a vertical drop hammer on the pipe piles.The HJC constitutive model of ECC was established based on key parameters obtained from static tension and compression tests and dynamic compression tests.The correctness of the finite element model was verified by split Hopkinson Pressure Bar (SHPB) tests.The parametric analysis conducted on the pipe pile models compounded with different hammer mass and impact velocity yielded dynamic responses including the displacement,time-history curve of energy,and effective plastic strain diagrams of the pipe piles under various …


Comparative Study Of Different Ventilation Methods During Tunnel Construction, Yue Kun, Bao Xiaohua, Ao Xiang, Liu Kuan, Wu Han, Li Tao, Shen Jun Oct 2024

Comparative Study Of Different Ventilation Methods During Tunnel Construction, Yue Kun, Bao Xiaohua, Ao Xiang, Liu Kuan, Wu Han, Li Tao, Shen Jun

Journal of China & Foreign Highway

The continuous improvement of tunnel construction technology brings a rapid increase in the speed and mileage of tunnel excavation,during which ventilation is a main problem affecting construction efficiency and safety.Taking the Zhuhai Xingye Express (West Line ) tunnel project as an example,this paper studied the influences of forced ventilation,exhaust ventilation,and hybrid ventilation on the dilution and discharge of harmful gas CO near the tunnel face and the wind speed in the tunnel.The results show that hybrid ventilation performs better in CO dilution,while exhaust ventilation has higher CO emission efficiency with a lower wind speed near the working face.Therefore,although forced ventilation …


Stability Of Excavation Face Of Double‑Mode Shield In Earth Pressure Mode Crossing Fault Zone Of Pearl River, Tong Bin, Zhang Bin, Zhu Hanbiao, Wang Shuying Oct 2024

Stability Of Excavation Face Of Double‑Mode Shield In Earth Pressure Mode Crossing Fault Zone Of Pearl River, Tong Bin, Zhang Bin, Zhu Hanbiao, Wang Shuying

Journal of China & Foreign Highway

In view of the stability of the excavation face of the double-mode shield crossing the fault zone of the Pearl River,the project of the section from Hongshengsha Station to Yufengwei Station of the second phase of Guangzhou Metro Line Seven was studied.Through numerical simulations conducted to analyze the whole area and the local high-risk area of the shield crossing the fault zone of the Pearl River,this paper explored the construction risk of the shield crossing process.Besides,this paper analyzed the influence of different support stresses and grouting pressures on the stability of the excavation face and ground deformation,and finally,the tunneling parameters …


Development Trend On Raw Materials Market Of Ready‑Mixed Concrete Under Green Construction, Ding Hu, Ding Qingjun, Lin Haojun, Zhang Zhen Oct 2024

Development Trend On Raw Materials Market Of Ready‑Mixed Concrete Under Green Construction, Ding Hu, Ding Qingjun, Lin Haojun, Zhang Zhen

Journal of China & Foreign Highway

In the face of resource depletion,high energy consumption in production,high carbon emissions,and serious pollution brought by traditional pumpcrete raw materials,a variety of new raw materials have been gradually developed and promoted to conform with the green construction promoted by China ’s civil engineering industry,witnessing a stable increase in quality,output,and social recognition.High-quality natural river sand and pebbles are in short supply at the origin,and they can be explored in old silted river channels.Gravel and manufactured sand produced using large particle size natural pebbles,limestone,construction waste,and others as raw materials will become new substitutes.In the transformation and upgrading of production enterprises which tend …


Review Of Snow And Ice Melting Techniques For Road And Bridge In Cold Regions, Tang Liyun, Shao Haitao, Tang Huaming, Qiu Peiyong, Du Xiaoqi, Zhang Lei, Peng Hui Oct 2024

Review Of Snow And Ice Melting Techniques For Road And Bridge In Cold Regions, Tang Liyun, Shao Haitao, Tang Huaming, Qiu Peiyong, Du Xiaoqi, Zhang Lei, Peng Hui

Journal of China & Foreign Highway

Snow and ice melting of road and bridge surfaces is crucial for traffic safety,but current research on snow and ice melting techniques mainly focuses on engineering effects and technical evaluation,without the analysis and elaboration from the perspective of their mechanisms.To this end,based on the different mechanisms,this study divided snow and ice melting techniques into three types and summarized them:passive deicing,active deicing,and energy utilization deicing.This study systematically evaluated the advantages and disadvantages of traditional deicing methods such as deicing agents and mechanical deicing,analyzed two active deicing techniques,namely inhibitive freezing pavement and phase change material pavement,discussed the environmental-friendly method for road deicing …


Post‑Evaluation Method For Decision‑Making And Implementation Of Highway Maintenance Projects Based On Ahp‑Dematel, Yu Wei, Yang Na, Li Jue Oct 2024

Post‑Evaluation Method For Decision‑Making And Implementation Of Highway Maintenance Projects Based On Ahp‑Dematel, Yu Wei, Yang Na, Li Jue

Journal of China & Foreign Highway

Addressing the current lack of post-evaluation management systems related to highways,particularly highway maintenance,this paper proposed a post-evaluation method for the decision-making and implementation of highway maintenance projects based on the combination of analytic hierarchy process (AHP) and decision-making trial and evaluation laboratory (DEMATEL ).After building a post-evaluation model for the decision-making and implementation of highway maintenance projects and designing the evaluation process,this paper calculated key factors influencing the post-evaluation of the decision-making and implementation of highway maintenance projects and their respective comprehensive weights.The research results indicate that decision-making can possess higher accuracy and efficiency under the above calculation method,providing a …


Effect Of Aging Temperature On Properties Of Sealant Under Field Construction Conditions, Liu Hanchao, Teng Xinhua, Zhang Jingyan, Zhang Kaihua, Lin Hui Jul 2024

Effect Of Aging Temperature On Properties Of Sealant Under Field Construction Conditions, Liu Hanchao, Teng Xinhua, Zhang Jingyan, Zhang Kaihua, Lin Hui

Journal of China & Foreign Highway

In order to study the influence of short-term aging temperature on the properties of sealant,a sealant was prepared,and field construction conditions were simulated.The properties of the sealant before and after short-term aging at 180‒220 ℃ were tested.The viscoelastic properties,physicochemical properties,and microstructures of the sealant were studied,and the mechanism of property changes was discussed.The results show that the cone penetration and flow value of the aged sealant decrease,while the softening point and elastic recovery rate increase.Aging at high temperature (>180 ℃) for a short time and low temperature (160 ℃) for a long time will cause obvious property changes.The tensile …


Experimental Study On Capillary Water‑Holding Characteristics Of Loess Backfill In Ecological Ditches, Nan Yalin, Zhang Xiaoyu, Chen Hong, An Peng, Liu Kui, Camara Ibrahima Kalil Jul 2024

Experimental Study On Capillary Water‑Holding Characteristics Of Loess Backfill In Ecological Ditches, Nan Yalin, Zhang Xiaoyu, Chen Hong, An Peng, Liu Kui, Camara Ibrahima Kalil

Journal of China & Foreign Highway

The municipal ecological ditches have the basic functions of accumulating water for infiltration in the rainy season and conserving moisture in the dry season.However,the design of loess backfill in ecological ditches is based on no evidence,which often leads to landscape vegetation drowning in the rainy season or dying in the dry season.For this reason,a study was carried out by remoulding loess with a small-size capillary water rise height test,a large-size water-holding characteristic model test,and an unsaturated numerical analysis.The results show that the final capillary water rise height of the soil column can reach 100 cm when the dry density is …


Research On Performance Of Coal Gangue Concrete, Wang Jiliang, Ma Wenhui, Xu Weidong, Lyu Zhigang Jul 2024

Research On Performance Of Coal Gangue Concrete, Wang Jiliang, Ma Wenhui, Xu Weidong, Lyu Zhigang

Journal of China & Foreign Highway

Coal gangue is an industrial solid waste produced in the process of raw coal mining.It has a large stock and a relatively low utilization rate.Using coal gangue as concrete aggregate can not only solve the environmental pollution caused by coal gangue storage but also make up for the shortage of natural sand and gravel resources,which opens up an effective way for the large-scale utilization of coal gangue.According to the application characteristics of coal gangue as concrete aggregate,the chemical component,mineral composition,and physical properties of coal gangue were systematically analyzed.The influence of coal gangue as aggregate on the working performance,mechanical properties,volume stability,and …


Experimental Study On Shear Performance Of Uhpc‑Nc Interface, Wan Zhiyong, Chen Jianping, He Shaohua, Huang Xu, Sun Xiangdong Jul 2024

Experimental Study On Shear Performance Of Uhpc‑Nc Interface, Wan Zhiyong, Chen Jianping, He Shaohua, Huang Xu, Sun Xiangdong

Journal of China & Foreign Highway

Ultra-high performance concrete (UHPC) has great application prospects in engineering structure reinforcement.The reliability of the bonding properties at the interface between the new UHPC reinforcement layer and the old concrete structure is critical for ensuring the serviceability of the reinforced structures.To determine the influence of different interface treatments on the bonding properties at the interface between the UHPC and normal concrete (NC),six Z-shaped UHPC-NC bonding specimens were designed,and the bonding properties of the UHPC-NC with three different kinds of interface,namely smooth,chisel,chisel + reinforced,were investigated.In addition,nonlinear finite element models for the concrete interface were established to determine the distribution law of …


Application Of Sequential Quadratic Programming Method In Cable Force Adjustment Of Cable‑Stayed Bridges, Xu Yufeng, Zhu Mengyang, Chen Si, Xie Yunfei Jul 2024

Application Of Sequential Quadratic Programming Method In Cable Force Adjustment Of Cable‑Stayed Bridges, Xu Yufeng, Zhu Mengyang, Chen Si, Xie Yunfei

Journal of China & Foreign Highway

When the construction of a cable-stayed bridge enters the completion stage,due to various factors,there is a certain error between the actual alignment and internal force of the structure and the theoretical completion state,and it is usually necessary to adjust the cable force.In order to calculate the cable force adjustment of a cable-stayed bridge in the adjustment stage,a method based on an influence matrix and sequential quadratic programming was proposed to solve the cable force adjustment.A large-span hybrid girder cable-stayed bridge was taken as the background,and the alignment and internal force response values of the structure with varying cable units were …


Protection Design Of Middle Piers Of Overpass Bridges Based On Double Protection Concept, Lyu Sizhong, Wang Xin, Guo Jianmin, Liu Siyuan, Li Yuxin, Yang Fuyu Jul 2024

Protection Design Of Middle Piers Of Overpass Bridges Based On Double Protection Concept, Lyu Sizhong, Wang Xin, Guo Jianmin, Liu Siyuan, Li Yuxin, Yang Fuyu

Journal of China & Foreign Highway

The collision accident types of middle piers of overpass bridges were summarized and analyzed,and it was proven that anti-collision and anti-scratching were two important requirements of pier protection.Then,the new concept of double protection and corresponding technical schemes were put forward.The first protection adopted the way of setting concrete barriers or ship-shaped elevating members on the periphery of the pier to prevent vehicles from impacting the pier,and the second protection used the self-wrapped steel plate or aluminum foam plate to prevent vehicles from scratching the pier.The safety of the pier protection structure schemes was verified by computer simulation and unit test,and …


Research On Yolov 5‑Ganomaly Joint Algorithm For High‑Strength Bolt Detection, Xie Haibo, Zhu Weijun, Zhang Bi2, Zhang Dahai Jul 2024

Research On Yolov 5‑Ganomaly Joint Algorithm For High‑Strength Bolt Detection, Xie Haibo, Zhu Weijun, Zhang Bi2, Zhang Dahai

Journal of China & Foreign Highway

High-strength bolt loosening detection of bridges faces problems such as heavy workload,small targets,many anomalies,and difficult collection.Therefore,this paper proposed a semi-supervised deep learning model,which could obtain the bolt loosening detection model even with a small number of negative samples and solve the problem of unbalanced model training samples.The accuracy of the YOLOv 5-CT model for bolt target detection reached 98.33%.By preprocessing bolt data,the reconstruction ability of bolt images by the Ganomaly model was improved.When the hidden space vector value was 100,the model had the highest SAUC and the best discriminant performance.In the model test stage,the threshold of abnormal fraction was set …


Experimental Study On Effect Of Temperature On Bound Water Adsorption And Deformation Of High Liquid Limit Soil, Zi Yinhui, Shen Xuning, Zhang Hao, Zhang Rui, Li Lu Jul 2024

Experimental Study On Effect Of Temperature On Bound Water Adsorption And Deformation Of High Liquid Limit Soil, Zi Yinhui, Shen Xuning, Zhang Hao, Zhang Rui, Li Lu

Journal of China & Foreign Highway

In order to study the effect of temperature change on the bound water content adsorbed by high liquid limit clay and the deformation law of high liquid limit clay embankment,the high liquid limit clay in Hainan Province was selected as the primary research object and compared with the low liquid limit sand in Hunan Province.The effect of temperature on the bound water content adsorbed by high liquid limit clay was explored through a nuclear magnetic resonance test.In addition,the effect of temperature on the deformation of high liquid limit clay embankments was analyzed through the consolidation test with a temperature-controlled consolidometer.The …


Temperature And Strain Development Characteristics Of Tunnel Concrete Based On Double Grating Sensors, Fang Jianping, Zhang Mengxi, Yao Xiaonan Jul 2024

Temperature And Strain Development Characteristics Of Tunnel Concrete Based On Double Grating Sensors, Fang Jianping, Zhang Mengxi, Yao Xiaonan

Journal of China & Foreign Highway

In order to better prevent tunnel concrete from cracking,the development law of concrete temperature and strain was studied.Based on the connection project of Sanjiang Middle Road in the Smart New City of Quzhou,a data acquisition system was established to monitor concrete temperature and strain on site.The defects of the traditional method that the temperature and strain monitoring are insensitive,and the monitoring data is discontinuous were overcome.In addition,the high-performance double grating temperature-strain sensor was used to simultaneously monitor the temperature and strain at the same position,and the temperature compensation method was used to overcome the influence of the ambient temperature on …


Properties And Mechanism Of Reclaimed Asphalt Based On Sbs Structure Repair, Feng Xinjun, Yang Hongyang, Xiao Honghai, Zhu Ziqiang Jul 2024

Properties And Mechanism Of Reclaimed Asphalt Based On Sbs Structure Repair, Feng Xinjun, Yang Hongyang, Xiao Honghai, Zhu Ziqiang

Journal of China & Foreign Highway

At present,the common asphalt regenerant is used for treating the aged styrene-butadiene-styrene (SBS) modified asphalt in China,which fails to repair the SBS cross-networking structure,resulting in the poor regeneration effect of the aged SBS modified asphalt.In this study,a new reactive regenerator containing a structural repair agent,extractive oil,plasticizer,solubilizer,and a small amount of SBS was used to regenerate the aged SBS modified asphalt.The conventional properties and rheological properties of reclaimed SBS modified asphalt were studied by three index tests,Brookfield viscosity test,dynamic shear rheological test,and low temperature bending rheological test.Then,a fluorescence microscope and infrared spectrometer were used to study the regeneration mechanism of the …


Research On General Drawing Design Technologies For Cover Culverts In Hunan Province, Peng Xiaoming, Li Yukun, Hu Qiong, Xia Yutao Jul 2024

Research On General Drawing Design Technologies For Cover Culverts In Hunan Province, Peng Xiaoming, Li Yukun, Hu Qiong, Xia Yutao

Journal of China & Foreign Highway

As one of the main structures of highways,a culvert has the characteristics of large quantity and wide range.Affected by design and construction factors,engineering diseases of culverts have been prominent for a long time.With the extensive promotion of the green highway construction concept and the continuous updating of technical standards and design specifications,the original general drawing of culverts fails to meet the needs of the sustainable and healthy development of highway construction under the new situation.Hunan Provincial Communications Planning,Survey & Design Institute has conducted extensive and in-depth investigation and research on the key technologies of highway culvert design and prepared a …


Transverse Deformation And Countermeasures Of Cantilever Assembly Of Super‑Wide Steel Box Girder Of Zhongshan Bridge Over Shenzhen‑Zhongshan Link, Zhou Yu Jul 2024

Transverse Deformation And Countermeasures Of Cantilever Assembly Of Super‑Wide Steel Box Girder Of Zhongshan Bridge Over Shenzhen‑Zhongshan Link, Zhou Yu

Journal of China & Foreign Highway

In view of the transverse deformation of super-wide steel box girders of cable-stayed bridges during the cantilever assembly,the construction characteristics of the two-way eight-lane super-wide steel box girder of Zhongshan Bridge over Shenzhen-Zhongshan Link were analyzed,and the main causes of the transverse deformation during the cantilever assembly of the super-wide steel box girder were investigated.According to the matching height difference adjustment technology in the cantilever assembly construction of the wide box girder in China and abroad,this paper innovatively proposed a matching process of straight beam locking + initial tension of hanging cables,which better solved the problem of poor transverse deformation …


Fume Emission And Environmental Impact Assessment In Fresh Asphalt Tunnel Construction Site, Deng Wenti, Zou Guilian, Zhang Yuan, Yu Liang, Xie Huiduan Jul 2024

Fume Emission And Environmental Impact Assessment In Fresh Asphalt Tunnel Construction Site, Deng Wenti, Zou Guilian, Zhang Yuan, Yu Liang, Xie Huiduan

Journal of China & Foreign Highway

In view of the random monitori ng of fum e emission in asphalt pavement construction sites,combined with the engineering application of fresh asphalt in the construction of hot-mixed and hot-spread asphalt pavement in large and long tunnels for fume emission reduction,the fume collection and evaluation method of asphalt pavement construction sites were studied,and the emission reduction effect of fresh asphalt was evaluated.The Summa tanks were used to collect the asphalt fume at different positions of the paver,and the asphalt fume was quantitatively analyzed by gas chromatograph-mass spectrometer (GC-MS).The results show that compared with the non-fresh asphalt from the same source,the …


Stability Analysis Of High And Steep Bank Slope Of Jinqi Bridge On Wudang‑Changshun Expressway, Wang Hao Jul 2024

Stability Analysis Of High And Steep Bank Slope Of Jinqi Bridge On Wudang‑Changshun Expressway, Wang Hao

Journal of China & Foreign Highway

Jinqi Bridge on the Wudang-Changshun Expressway in Guizhou Province crosses the Maotiao River,and the poor geological conditions such as dangerous rock mass and collapse accumulation body on the bank slope of the river are relatively developed,which seriously affects the site selection and safety of the bridge.In order to study the stability of the high and steep bank slope of the bridge,the paper explored the main poor geological conditions in the bridge site through a comprehensive air-ground investigation.By means of numerical analysis,InSAR,and other technologies,the movement range of dangerous rock mass on the bank slope was quantitatively evaluated.The stability and deformation mode …


Shear Creep Characteristics And Slope Deformation Mechanism Of Siliceous Slate, Li Jian, Yan Liangyu, Yu Kaibing, Li Ming, Yan Tingzhou, Zhao Jia Jul 2024

Shear Creep Characteristics And Slope Deformation Mechanism Of Siliceous Slate, Li Jian, Yan Liangyu, Yu Kaibing, Li Ming, Yan Tingzhou, Zhao Jia

Journal of China & Foreign Highway

To study the time-dependent creep effect of siliceous slate and the deformation and failure evolution law of high slope,in this paper,the shear creep test of indoor rock mass was carried out to plot the shear creep duration curves of siliceous slate under different normal stresses,the shear displacement-time curve,and the creep rate-time curve under different normal loads and shear loads.The average creep rate and shear load variation of siliceous slate were studied,and the long-term shear strength parameters of siliceous slate were determined by the steady-state creep rate method.The results show that in the creep test,the sensitivity of cohesion is significantly greater …


Rotating Wheel Tracking Tester And Torsional Resistance Of Asphalt Mixtures, Yao Hongru, Wang Qiang, Lu Guangyan, Zhou Xiaolong Jul 2024

Rotating Wheel Tracking Tester And Torsional Resistance Of Asphalt Mixtures, Yao Hongru, Wang Qiang, Lu Guangyan, Zhou Xiaolong

Journal of China & Foreign Highway

Asphalt pavement is prone to pla stic deformation and aggregate raveling when it is in torsion.At present,there is no standard test method and equipment to evaluate the torsional resistance of asphalt mixtures.In order to study the effective evaluation method for the torsional shear resistance of asphalt mixtures,this paper introduced the structures and working principles of three kinds of equipment developed in Japan.The torsional resistance of five typical asphalt mixtures was evaluated by rotating wheel tracking tests,and factors affecting the torsional resistance of asphalt mixtures were analyzed.The results show that the types of structures and binders of asphalt mixtures have an …


Construction Of Carbon Emission Monitoring And Management System For Commercial Vehicles, Chang Zheng, Song Yan, Ji Meichen, Liu Yuqing, Wang Jing Jul 2024

Construction Of Carbon Emission Monitoring And Management System For Commercial Vehicles, Chang Zheng, Song Yan, Ji Meichen, Liu Yuqing, Wang Jing

Journal of China & Foreign Highway

To construct a comprehensive carbon emission monitoring and management system for commercial vehicles,firstly,this article described the background and significance of carbon emission monitoring and management of commercial vehicles and summarized the research in relevant fields in China and abroad.Then,this article expounded on the carbon emission monitoring system for commercial vehicles,which covered three major levels:monitoring target layer,monitoring implementation layer,and monitoring summary layer,so as to achieve comprehensive and accurate carbon emission monitoring.Finally,combined with the carbon emission monitoring data of commercial vehicles,this article put forward a carbon emission management system for commercial vehicles based on data information,including carbon emission data sharing and opening,data …


Experimental Study On Reinforced Geogrid Of Construction And Demolition Wastes Based On Dic Technology, Tan Peng, Li Hai, Li Xiangping, Gu Fan, Zhang Junhui Jul 2024

Experimental Study On Reinforced Geogrid Of Construction And Demolition Wastes Based On Dic Technology, Tan Peng, Li Hai, Li Xiangping, Gu Fan, Zhang Junhui

Journal of China & Foreign Highway

In order to control differential settlement caused by new and old subgrade connections after expressway reconstruction and expansion,this paper proposed a layered treatment structure for the loose steps of the old road with high water content.A layer of construction and demolition waste was laid on the step surface of the old road to wrap the geogrid.The treatment effect was compared with that of sand wrapping and lime mixing,and the digital speckle correlation (DIC) was used to observe the reinforced influence zone,so as to determine the thickness of different layers of the subgrade wrapped by construction and demolition wastes.The particle rotation …


Working Performance Of Rigid Airfield Runway Considering Influence Of Cavity Depth, Dai Xuan, Li Zhao, Cai Jing, Li Yue, Liu Guoguang, Qi Lin Jul 2024

Working Performance Of Rigid Airfield Runway Considering Influence Of Cavity Depth, Dai Xuan, Li Zhao, Cai Jing, Li Yue, Liu Guoguang, Qi Lin

Journal of China & Foreign Highway

In order to analyze the influence of cavity depth on runway safety,a numerical simulation was carried out using the finite difference method.A total of 208 sets of different working conditions were designed by taking into account factors such as different aircraft types,runway dimensions,and cavity depth and area.Based on the runway life model considering the exponential decay of the structural condition,an analytical method was proposed to evaluate the impact of the cavity on the runway life.The results show that the bending and stress of the runway increase gradually with the increase in the cavity depth,but the growth rate is getting slower …


Intelligent Compaction Of Asphalt Pavement And Its Key Influencing Factors, Zhu Huifang, Wang Liang Jul 2024

Intelligent Compaction Of Asphalt Pavement And Its Key Influencing Factors, Zhu Huifang, Wang Liang

Journal of China & Foreign Highway

Intelligent compaction,as a new type of road construction quality monitoring and management technology,has been widely used in the compaction process of asphalt pavement.However,due to the lack of understanding of the compaction process and the interaction mechanism between asphalt mixture particles,the problems of over-compaction and non-uniformity of compaction often occur in the actual construction,which seriously affects the quality of road construction and service performance.In this study,through the combination of the engineering field and indoor tests,the variation characteristics of asphalt mixture compaction with the number of compaction were analyzed by using the semi-variance function of the geostatistical model,and the effect of temperature …


Influence Of Lateral Constraint Conditions And Compactness On Compression Characteristics Of Compacted Loess In Northern Shaanxi, Chang Yinghong, Zhao Jinpeng, Zhang Xiaozhou, Yang Hao, Li Zhe, Shao Dengfeng, Liu Lulu Jul 2024

Influence Of Lateral Constraint Conditions And Compactness On Compression Characteristics Of Compacted Loess In Northern Shaanxi, Chang Yinghong, Zhao Jinpeng, Zhang Xiaozhou, Yang Hao, Li Zhe, Shao Dengfeng, Liu Lulu

Journal of China & Foreign Highway

In recent years,with the rapid development of road engineering construction,subgrade settlement caused by vertical compression of compacted loess has become increasingly serious.The previous research on the deformation of compacted loess mostly focuses on moisture content,porosity,saturation,and other aspects,ignoring the influence of lateral constraint conditions and different compaction on compacted loess.To address these issues,based on the reconstruction and expansion project of G 307 road in northern Shaanxi,this paper selected compacted soil samples of subgrade on site to carry out indoor compression tests.By applying different lateral constraint conditions,the stress-strain curves of compacted loess subjected to vertical multistage load under different compactness and confining …


Performance Of Composite Modified Permeable Concrete With Nano‑Silicon And Polypropylene Fiber, Liu Benli, Zhang Peng, Shan Jingsong, Zhao Haijian, Su Benjun, Li Chao Jul 2024

Performance Of Composite Modified Permeable Concrete With Nano‑Silicon And Polypropylene Fiber, Liu Benli, Zhang Peng, Shan Jingsong, Zhao Haijian, Su Benjun, Li Chao

Journal of China & Foreign Highway

In order to improve the comprehensive performance of permeable concrete,nano-silicon and polypropylene fiber were added to permeable concrete to study the performance of the composite modified permeable concrete.Firstly,the influence of single-doped nano-silicon on the performance of cement paste and permeable concrete was studied,and the content of nano-silicon and the optimal water-to-binder ratio were determined.On this basis,different proportions of polypropylene fiber were mixed,and the reasonable content of polypropylene fiber was determined.The results show that nano-silicon improves the porosity of permeable concrete and increases the optimal water-to-binder ratio.When the content of nano-silicon is 0.5%,and the water-to-binder ratio is 0.32,the compressive strength of …