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Full-Text Articles in Materials Science and Engineering

Design Of Super Large Cantilever Wing ⁃Box Girder Bridge, Zhong Hao Jul 2023

Design Of Super Large Cantilever Wing ⁃Box Girder Bridge, Zhong Hao

Journal of China & Foreign Highway

In recent years, with the rapid development of urban bridge construction, the bridge inevitably needs to cross the existing railway and road in the construction project. This kind of bridge has the characteristics of a large span and limited pier space. At the same time, in order to meet the increasing traffic demand, the transverse width of the bridge is increasing, so the application of large cantilever wing-box girder structures is becoming more and more extensive. Based on the overspan railway bridge project of the northern section of the Wuhan Fourth Ring Line (Wuhu–Wujiashan), this paper introduced the design difficulties …

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Study On Reasonable Seismic System Of Long ⁃Span Concrete Beam Bridge In Strong Earthquake Areas, Yu Deen, Han Shanjian, Sun Pingkuan Jul 2023

Study On Reasonable Seismic System Of Long ⁃Span Concrete Beam Bridge In Strong Earthquake Areas, Yu Deen, Han Shanjian, Sun Pingkuan

Journal of China & Foreign Highway

In this paper, a three-dimensional finite element dynamic model of the Longtang Nandujiang Bridge in Hainan Province was established. Firstly, the selection of ground motion input and the establishment of the finite element model were introduced. Secondly, the influence of different design parameters (support radius) of the friction pendulum bearing on the seismic response of the bridge was discussed, and the optimal bearing parameters suitable for the bridge were obtained. Finally, the seismic responses of the bridge under three different constraint structures, namely conventional constraint system, seismic isolation system of friction pendulum bearing, and rigid frame bridge system, were compared. …

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Calculation Of Arch Rib Installation Alignment Of Large Span Cable Hoisting Arch Bridge, Xiong Shaohui, Guo Xin, You Zuoqiao Jul 2023

Calculation Of Arch Rib Installation Alignment Of Large Span Cable Hoisting Arch Bridge, Xiong Shaohui, Guo Xin, You Zuoqiao

Journal of China & Foreign Highway

Cable hoisting method is the most important construction method for long-span arch bridges. In the process of arch rib lifting, the partial consolidation of the joint caused by temporary bolt connection, the deflection of the tower caused by the temporary construction load of the main cable, and the free expansion of the anchor cable and the buckle cable caused by temperature change will have a great influence on the installation alignment of the arch rib. In this paper, a two-element model method considering stiffness loss was used to calculate the correction value of the arch rib installation alignment more accurately …

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Thickness Detection Of Reinforced Concrete Protective Layer Based On Environ Mental Calibration, Hong Hua, Xu Jianhong, Cao Sugong, Fu Junlei Jul 2023

Thickness Detection Of Reinforced Concrete Protective Layer Based On Environ Mental Calibration, Hong Hua, Xu Jianhong, Cao Sugong, Fu Junlei

Journal of China & Foreign Highway

In order to solve the problem of inaccurate detection of reinforced concrete protective layer thickness in engineering, this paper studied and formed a reasonable and perfect method and calibration procedure for the detection of reinforced concrete protective layer thickness in highway and water transportation engineering by using the analysis of influencing factors. The results show that the accuracy of measuring the protective layer thickness of reinforced concrete in practical engineering can be effectively improved. The production of standard instrument calibration specimens can be saved, and the testing process can be standardized.

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Correlation Analysis Between External Damages And Transverse Load Distribution Capacit Y Of Hollow Slab Bridges, Cao Hao, Sun Dunhua, Wang Zichen, Zhao Fuli, Sun Haipeng, Xiong Wen Jul 2023

Correlation Analysis Between External Damages And Transverse Load Distribution Capacit Y Of Hollow Slab Bridges, Cao Hao, Sun Dunhua, Wang Zichen, Zhao Fuli, Sun Haipeng, Xiong Wen

Journal of China & Foreign Highway

To correctly evaluate the service status of prefabricated hollow slab girder bridge, based on the measured data of apparent disease and load test of hollow slab girder bridge in reconstruction and expansion project, this paper first analyzed the data characteristics of the beam body, hinge joints, and support disease samples and obtained their statistical distribution rules. Then, according to the typical diseases (transverse cracks and hinge cracks at the bottom of the beam), the BP neural network was used to build a correlation model for them, and the close correlation between the two typical diseases of hollow slab girder bridge …

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Research Of Disease Analysis And Reinforcement Technology For Typical Orthotropic Bridge Deck, Guo Fukuan, Zhou Shangmeng Jul 2023

Research Of Disease Analysis And Reinforcement Technology For Typical Orthotropic Bridge Deck, Guo Fukuan, Zhou Shangmeng

Journal of China & Foreign Highway

In order to effectively solve the disease problem of orthotropic steel bridge decks, this paper relied on a steel box girder cable-stayed bridge deck reinforcement project to carry out steel bridge deck disease analysis and reinforcement technology research. The results show that the main disease of steel bridge decks is fatigue cracking. The fatigue cracks are numerous, short, and deep, and they continuously grow and cause more severe disease. The excessive fatigue stress amplitude is the main factor leading to the fatigue cracking of steel bridge decks. Once the crack occurs, the stress amplitude of the crack tip increases continuously, …

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Analysis Of Installation Method And Error Control Of Steel Girder Of Steel ⁃Concrete Composite Girder Cable ⁃Stayed Bridge, Xiong Xianyong, Fu Yajun, Huang Gen Jul 2023

Analysis Of Installation Method And Error Control Of Steel Girder Of Steel ⁃Concrete Composite Girder Cable ⁃Stayed Bridge, Xiong Xianyong, Fu Yajun, Huang Gen

Journal of China & Foreign Highway

Compared with cable-stayed bridges with pure steel girders, the installation of a steel main girder of the steel⁃concrete composite girder cable⁃stayed bridge is more complicated, and the installation error control is more difficult. In this paper, the composite girder with a double box section was taken as the research object, and a finite element model was established to compare the installation methods of steel main girders. The best installation method was selected according to the principle of safety loading, and the causes of the installation errors of steel main girders were analyzed. The corresponding error control methods were proposed.

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Cable⁃Stayed Bridge Of Cable Auxiliary Beam Arch Pylon ⁃Key Technologies Design Of Meishan Minjiang Bridge, Ma Zhendong, Lai Yaping, Chen Jiayong Jul 2023

Cable⁃Stayed Bridge Of Cable Auxiliary Beam Arch Pylon ⁃Key Technologies Design Of Meishan Minjiang Bridge, Ma Zhendong, Lai Yaping, Chen Jiayong

Journal of China & Foreign Highway

The newly built Minjiang Bridge in Meishan City, Sichuan Province applies the concept of cable-assisted girder bridge. P4 steel arch tower combined with three-stage balanced double-plane cable and P3 and P5 auxiliary towers combined with thin cable of single cable plane were used to assist the load on the beam body, making the 2.5 m-high concrete main beam meet the requirements of the main span of 2 × 120 m. Through the analysis of the bearing force, the angle between the double-limb arch tower was 43.6°, and two pairs of cables were set in the auxiliary tower to achieve the …

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Aesthetic Design Of Hechuan Qujiang Landscape Bridge, Zheng Guangqin, Chen Jiayong, Li Yue, Lai Yaping, Qiao Yunqiang Jul 2023

Aesthetic Design Of Hechuan Qujiang Landscape Bridge, Zheng Guangqin, Chen Jiayong, Li Yue, Lai Yaping, Qiao Yunqiang

Journal of China & Foreign Highway

Hechuan Qujiang Landscape Bridge is located at the junction of Qujiang River and Jialing River. It is a 1 × 400 m simple supported single-cable surface ground anchor suspension bridge. The main girder is a steel box girder arranged with curved branches. One side is the highway system to meet the needs of motor vehicles across the river, and the other side is the greenway system to meet the needs of pedestrians and non-motor vehicles. In the design process, the aesthetic design of the bridge was fully studied from four aspects: environment aesthetics, structure aesthetics, function aesthetics, and form aesthetics. …

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Study On Optimal Layout Of Cross ⁃Diaphragm In Oblique Small Box Girder, Mai Xinhao Jul 2023

Study On Optimal Layout Of Cross ⁃Diaphragm In Oblique Small Box Girder, Mai Xinhao

Journal of China & Foreign Highway

In order to determine the optimal layout of the cross⁃diaphragms in the oblique small box girder, a prestressed concrete small box girder bridge with a 50 m span was taken as the research object, and its internal force under the load of the moving beam was numerically simulated and measured. First, the model was modified according to the measured stress data, and the maximum distance between the cross⁃diaphragms was determined by using the warping-limited normal stress. Then, the height and thickness of the middle cross⁃diaphragms were determined according to the deflection difference coefficient of the bridge span. Finally, according to …

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Non⁃Gaussian Features Of Fluctuating Wind Pressures Under Combined Axle Condition, Chen Zhiqiang Jul 2023

Non⁃Gaussian Features Of Fluctuating Wind Pressures Under Combined Axle Condition, Chen Zhiqiang

Journal of China & Foreign Highway

In view of the non-Gaussian characteristics of wind pressure on the train surface of a typical high-speed railway train and bridge system, the Gaussian variable was expressed as a Hermite polynomial considering non-Gaussian variables by using Hermite series expansion method, and the probability density curve and peak factor of train surface were analyzed. The results show that the Davenport peak factor based on Gaussian distribution obviously underestimates the non-Gaussian peak factor, and its probability density curve deviates from the actual curve of the measuring point. The Hermite series peak factor method based on the modified method takes into account the …

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Application Of 3d Reconstruction Model In Inspection Of Bridge Apparent Defects, Xu Guangli, Li Shaoyong, Tang Jun, Liu Shuqi, Zhou Yin Jul 2023

Application Of 3d Reconstruction Model In Inspection Of Bridge Apparent Defects, Xu Guangli, Li Shaoyong, Tang Jun, Liu Shuqi, Zhou Yin

Journal of China & Foreign Highway

In view of problems such as low efficiency, poor accuracy, and imprecise three-dimensional (3D) location of defects in apparent defect inspection of bridges, this paper proposed a method for apparent defect inspection of bridges based on a 3D reconstruction model. By taking the indoor rectangular beam as the object, a three-dimensional bridge model was established, and its accuracy was verified. Then, based on the point cloud data derived from the model, a program was written in Python to realize the identification, measurement, and parameter derivation of apparent defects of bridges. Dade Bridge in Kunming, Yunnan Province was set as the …

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Design And Construction Of Steel Caisson For Inclined Pilecap Of Beitstadsund Bridge In Norway, Yang Dingjun Jul 2023

Design And Construction Of Steel Caisson For Inclined Pilecap Of Beitstadsund Bridge In Norway, Yang Dingjun

Journal of China & Foreign Highway

At present, the underwater bridge foundation construction technology in China and abroad has been relatively mature, but the different geographical environments, hydrogeological conditions, the form of basic structure, and the available construction equipment lead to different construction schemes and technologies. The Beitstadsund Bridge in Norway is located near the Arctic Circle in central Norway and across the strait. In the design and construction of the deep-water steel cofferdam of the inclined steel pile cap for the bridge, the overall installation of the steel cofferdam was realized by setting the cofferdam support on the inclined steel pipe group, the overall positioning …

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Study On Correction Method Of Cable Length Error In Construction Control Of Cable ⁃Stayed Bridges, Huang Gen, Chen Changsong Jul 2023

Study On Correction Method Of Cable Length Error In Construction Control Of Cable ⁃Stayed Bridges, Huang Gen, Chen Changsong

Journal of China & Foreign Highway

In order to effectively correct the stay cable length error during the construction of the cable-stayed bridge, this paper proposed a correction method with the exposure of the sockets as the error control index and analyzed the influence of the elastic modulus, temperature effect, and anchor point coordinates of the cable on the cable length error from the perspective of construction control. Then, error correction was achieved by adjusting the position of the manufacturing cable length and the nut at the anchor end. The results of application in Jiayu Yangtze River Highway Bridge show that this method can improve the …

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Analysis Of Mechanical And Deformation Characteristics Of Karst Tunnel Structure And Research On Treatment Technology, Huang Haifeng, Chang Zhenchao, Luo Junhui, Zhou Xiang, Ceng Fuquan, Tian Fapai Jul 2023

Analysis Of Mechanical And Deformation Characteristics Of Karst Tunnel Structure And Research On Treatment Technology, Huang Haifeng, Chang Zhenchao, Luo Junhui, Zhou Xiang, Ceng Fuquan, Tian Fapai

Journal of China & Foreign Highway

Combined with the construction process of Nongmo Karst Tunnel on Du’an–Bama Expressway, this paper used Midas-GTS finite element calculation software to conduct numerical simulation research on the stability of surrounding rock and treatment structure of tunnel with karst caves on either side, analyzed the influence of tunnel excavation on the stress and deformation characteristics of surrounding rock and supporting structure, and probed into the treatment effect of biased wall and root pile on the treatment of karst tunnel. The results show that the surrounding rock at the bottom of the tunnel, the top of the composite foundation, and the top …

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Influence Of Proximity Construction Of A New Pile Foundation On Adjacent Metro Tunnel, Jin Shengji, Mu Anxin, Bi Bo, Xu Chao, Yu He Jul 2023

Influence Of Proximity Construction Of A New Pile Foundation On Adjacent Metro Tunnel, Jin Shengji, Mu Anxin, Bi Bo, Xu Chao, Yu He

Journal of China & Foreign Highway

The construction of a bridge pile foundation and cap not only causes disturbance to its foundation and surrounding soil but also has a certain influence on adjacent existing structures. In order to study the influence of new pile foundation proximity construction on tunnels adjacent to subway sections, this paper took the pile foundation construction process of auxiliary bridge extension on both sides of Shenyang Changqing Bridge as the research object and adopted Midas/GTS finite element numerical simulation and construction monitoring methods to study the influence of new pile foundation proximity construction on tunnels adjacent to subway sections. The results show …

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Research On Crack And Permeability Characteristics Of Cement ⁃Modified Expansive Soil Under Dry ⁃Wet Cycles, Bao Guiyong, Xu Yangshaojun, Jiang Zhijie, Rong Hongliu, Wang Jinlong Jul 2023

Research On Crack And Permeability Characteristics Of Cement ⁃Modified Expansive Soil Under Dry ⁃Wet Cycles, Bao Guiyong, Xu Yangshaojun, Jiang Zhijie, Rong Hongliu, Wang Jinlong

Journal of China & Foreign Highway

In order to study the engineering permeability characteristics of cement-modified expansive soil under dry and wet cycles, the mix ratio of cement-modified expansive soil was designed, and the orthogonal design test method was adopted. Image analysis software PACS, unconfined compressive strength test, and laboratory permeability test were used to study the crack development, strength attenuation characteristics, and permeability changes of cement-modified expansive soil under dry and wet cycle conditions. The results show that soil permeability and strength are greatly affected by the number of dry and wet cycles. Under the condition of dry and wet cycles, the moisture content of …

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Study On Influence Of Freeze ⁃Thaw Cycles On Shear Properties Of Fly Ash Modified Saline Soil, Cheng Zhuo, Cui Gaohang, Gao Zening, Hou Zhao, Gang Haohang Jul 2023

Study On Influence Of Freeze ⁃Thaw Cycles On Shear Properties Of Fly Ash Modified Saline Soil, Cheng Zhuo, Cui Gaohang, Gao Zening, Hou Zhao, Gang Haohang

Journal of China & Foreign Highway

In order to explore the shear strength of fly ash-modified saline soil subgrade under the freeze-thaw cycle, saline soil samples from Suihua–Daqing Expressway were selected for direct shear test under different fly ash contents. The results show that the cohesive force and internal friction angle of the saline soil decrease after several freeze-thaw cycles. With the increase in fly ash content, the internal friction angle, cohesive force, and shear strength of the improved saline soil increase first and then decrease. When the fly ash content is 15%, the cohesive force, internal friction angle, and other mechanical indexes of the saline …

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Effect Of Temperature And Light On Characteristics Of Asphalt Emissions, Zhu Xuwei, Tian Bo Jul 2023

Effect Of Temperature And Light On Characteristics Of Asphalt Emissions, Zhu Xuwei, Tian Bo

Journal of China & Foreign Highway

In order to study the effects of temperature and light on the characteristics of asphalt emissions, atmospheric pressure chemical ionization–time-of-flight mass spectrometer (APCI‑TOF MS) and electron impact ionization mass spectrometry (EI‑MS) were used to quantitatively characterize the composition information of PG 62-22 asphalt emissions at different temperatures (40–200 °C). The effects of different temperatures and light on total emission factor, SOA conversion factor, intermediate volatile organic compound (IVOC)/semi-volatile organic compound (SVOC) volume fraction, and aromatics volume fraction of asphalt emissions were studied. The results show that the components of asphalt emissions change with temperature, and the components are complex and …

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Study On Triaxial Mechanical Properties Of Glass Fiber Reinforced Cement Soil In Short Age, Wang Wei, Dai Mengdan, Yu Wenjie Jul 2023

Study On Triaxial Mechanical Properties Of Glass Fiber Reinforced Cement Soil In Short Age, Wang Wei, Dai Mengdan, Yu Wenjie

Journal of China & Foreign Highway

In order to evaluate the improvement effect of fiber on the brittle damage of cement soil, a triaxial unconsolidated undrained (UU) test was carried out on glass fiber cement soil (GCS) with a curing age of 7 d and a mass fraction of glass fiber (GF) of 0, 2‰, 4‰, 6‰, and 8‰, respectively. The results show that: ① GCS retains the original strain softening characteristics of cement soil; ② For the same mass fraction of GF, the peak stress, peak strain, and residual strength of GCS samples increase gradually with the increase in confining pressure, but the brittleness index …

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Study On Experimental Application Of Xinjiang Steel Slag In Cement Stabilized Base, Chen Wei, Yu Haiming, Li Qian, Huang Yong, Si Yi Jul 2023

Study On Experimental Application Of Xinjiang Steel Slag In Cement Stabilized Base, Chen Wei, Yu Haiming, Li Qian, Huang Yong, Si Yi

Journal of China & Foreign Highway

Based on the experimental study of Xinjiang steel slag in cement-stabilized base, the physical and chemical characteristics of steel slag were analyzed, and the unconfined compressive strength, splitting strength, and dry shrinkage performance of cement-stabilized steel slag and gravel mixture with different cement dosages (4% and 5%) and steel slag contents (30%, 40%, and 60%) were analyzed. The test results show that steel slag can be used as a good engineering aggregate in a cement-stabilized base, and with the addition of steel slag, the unconfined compressive strength and splitting strength of steel slag and gravel mixture are increased to varying …

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Research On Cyclic Accumulative Strain Characteristics Of Structured Soft Clay, Ding Zhi, Yu Jiangang, Sun Miaomiao, Wang Jiawei, Ye Ke Jul 2023

Research On Cyclic Accumulative Strain Characteristics Of Structured Soft Clay, Ding Zhi, Yu Jiangang, Sun Miaomiao, Wang Jiawei, Ye Ke

Journal of China & Foreign Highway

Due to its structural properties, natural soft clay is prone to produce large cumulative deformation under cyclic loads such as traffic, which has a great impact on engineering. In order to solve the deformation problem caused by structural failure of soft clay under dynamic action, dynamic characteristics of undisturbed soft clay near a highway in Hangzhou were tested by the dynamic triaxial device under cyclic loading, and the dynamic characteristics of saturated undisturbed soft clay under different effective consolidation confining pressures, vibration frequencies, and dynamic stress ratios under K0 (static earth pressure coefficient) consolidation conditions were studied. The results show …

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Effect Of Activator On Compressive Strength Of Steel Slag Powder Cement Soil, Chen Fei, Wang Yanchun, Du Sujun Jul 2023

Effect Of Activator On Compressive Strength Of Steel Slag Powder Cement Soil, Chen Fei, Wang Yanchun, Du Sujun

Journal of China & Foreign Highway

In order to reasonably solve the environmental pollution caused by steel slag, steel slag powder was used to improve cement soil. The optimal mix ratio was determined by a laboratory unconfined compressive strength test to prepare steel slag powder cement soil. In view of of low activity and limited compressive strength enhancement effect of steel slag powder, three kinds of activators including sodium hydroxide, silica fume, and calcium chloride were selected to be added to steel slag powder cement soil, so as to study the strength variation rule. The results show that the strength of cement soil can be improved …

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Experimental Study On Time ⁃Varying Characteristics Of Saturated Water Content Of Granite Residual Soil In Acid⁃Etched Environment, Zhang Maolin, Xie Qingzhong, Fu Helin, Zhang Meng, Li Qinglong, Dong Hui Jul 2023

Experimental Study On Time ⁃Varying Characteristics Of Saturated Water Content Of Granite Residual Soil In Acid⁃Etched Environment, Zhang Maolin, Xie Qingzhong, Fu Helin, Zhang Meng, Li Qinglong, Dong Hui

Journal of China & Foreign Highway

In order to clarify the correlation between saturated water content variability and slope stability, characteristic tests on saturated water content of granite residual soil affected by acid were carried out. Direct shear tests were carried out to test the variation rule of saturated water content and its characteristic value under the influence of vertical loading and acidification time, and the internal causes of variation were deduced based on the structural characteristics obtained by microscope electron microscopy. The results show that: ① The vertical pressure σ = 300 kPa is the turning point of the linear and nonlinear relationship, and under …

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Mechanical Properties And Micro Analysis Of Cement Stabilized Steel Slag Macadam Base, Wan Tianbao Jul 2023

Mechanical Properties And Micro Analysis Of Cement Stabilized Steel Slag Macadam Base, Wan Tianbao

Journal of China & Foreign Highway

With steel slag as coarse aggregate, cement-stabilized steel slag macadam base material was designed and prepared by selecting three kinds of cement dosage and three kinds of steel slag content. The mechanical properties of cement-stabilized steel slag macadam base were studied through compaction and unconfined compressive strength tests, and XRD and SEM microscopic tests were carried out to analyze the mineral composition and microscopic morphology of steel slag and mixture and clarify the internal mechanism of hydration product formation and microstructure and strength formation. The results show that the maximum dry density and optimum moisture content of cement-stabilized steel slag …

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Analysis Of Influence Of Moisture Content ⁃Temperature Dual Factor On Mechanical Properties Of Red Clay, Wang Jiangtao, Bao Temenbaiyila, Yang Weiguang, Zhou Qi, Fu Helin Jul 2023

Analysis Of Influence Of Moisture Content ⁃Temperature Dual Factor On Mechanical Properties Of Red Clay, Wang Jiangtao, Bao Temenbaiyila, Yang Weiguang, Zhou Qi, Fu Helin

Journal of China & Foreign Highway

Under the new climatic environment and engineering construction requirements, engineering problems involving red clay are becoming more and more prominent, and it is urgent to deeply grasp the mechanical and engineering properties of residual slope red clay. The typical red clay in Hunan Province was studied in this paper. Based on the unconsolidated undrained direct shear test, this paper studied the mechanical properties of residual slope red clay under the influence of moisture content and temperature, focusing on the most unfavorable conditions affecting the mechanical properties of red clay. The results show that: ① The shear strength of red clay …

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Influence Of Steel Fiber And Polymer Emulsion On Mechanical Properties And Microstructure Of Concrete, Guo Guanglei, Sun Shiqiang, Li Ying, Zheng Yiwei, Mei Yingjun Jul 2023

Influence Of Steel Fiber And Polymer Emulsion On Mechanical Properties And Microstructure Of Concrete, Guo Guanglei, Sun Shiqiang, Li Ying, Zheng Yiwei, Mei Yingjun

Journal of China & Foreign Highway

The microstructure and mechanical properties of concrete were improved by adding steel fiber and polymer emulsion. The working properties and mechanical properties of steel fiber concrete, polymer emulsion-modified concrete, and steel fiber polymer concrete were tested at 3 d, 28 d, and 90 d. Nitrogen adsorption test, mercury injection test, and density method were used to obtain the total pore volume, median pore size, and closed porosity of concrete. The influence of steel fiber and polymer emulsion on the microstructure and mechanical properties of concrete was analyzed. The results show that the compressive strength of concrete after adding steel fiber …

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Effect Of Nano ⁃Metakaolin On Frost Resistance Of Concrete, Li Zhenfa Jul 2023

Effect Of Nano ⁃Metakaolin On Frost Resistance Of Concrete, Li Zhenfa

Journal of China & Foreign Highway

The denudation per unit area, relative dynamic elastic modulus, mechanical strength, and fracture characteristics of concrete with different nano-metakaolin contents before and after freezing and thawing were studied. The results show that nano-metakaolin can significantly improve the freezing resistance of concrete, and the denudation per unit area and relative dynamic elastic modulus loss rate of modified concrete are significantly improved compared with the reference group. The mechanical strength and fracture properties of nano-mekaolin-modified concrete before and after freezing and thawing are higher than those of the control group, and the mechanical strength, fracture toughness, and fracture energy loss rate are …

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Traffic Conflict Analysis Of Multila Neexpressway Based On Simulation, Ceng Yuekai, Zhou Tao, Chen Yazhen Jul 2023

Traffic Conflict Analysis Of Multila Neexpressway Based On Simulation, Ceng Yuekai, Zhou Tao, Chen Yazhen

Journal of China & Foreign Highway

In order to prevent traffic accidents on multi-lane expressways, the VISSIM traffic simulation model was established based on three types of multi-lane traffic conflicts: mixed passenger and cargo type, separated passenger and cargo type, and separated main and auxiliary type. SSAM software was used to obtain traffic conflict data, and the form, quantity, and location of the conflicts were analyzed. The results show that traffic conflicts are the most under the mixed passenger and cargo type, which are mainly distributed in the upper 100 m range of the innermost lane, outermost lane, and deceleration lane. The traffic conflicts under the …

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Risk Analysis Of Highway Nighttime Maintenance Operation Based On Sem, Fan Jinhua, Zou Leping, Qi Shaoren, Tian Zhen Jul 2023

Risk Analysis Of Highway Nighttime Maintenance Operation Based On Sem, Fan Jinhua, Zou Leping, Qi Shaoren, Tian Zhen

Journal of China & Foreign Highway

In order to analyze the factors affecting the risk of nighttime expressway maintenance operation and quantitatively assess the degree of influence of various factors on the risk of nighttime maintenance operation, this paper extracted five first-level indicators and 36 second-level indicators that affect the risk of operation through literature review, accident data, and questionnaire survey and built an evaluation system. The first-order and second-order confirmatory factor analysis models were constructed by using a structural equation model (SEM) based on 343 questionnaires of the nighttime maintenance operation risks. The results show that the driver factor has the greatest effect on the …

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