Non⁃Gaussian Features Of Fluctuating Wind Pressures Under Combined Axle Condition,
2023
Shandong Railway Investment Holding Group Co., Ltd., Jinan, Shandong 250014, China
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 …
Application Of 3d Reconstruction Model In Inspection Of Bridge Apparent Defects,
2023
1. Yunnan Kun-Chu Expressway Investment and Development Co., Ltd., Kunming, Yunnan 650100, China;
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 …
Design And Construction Of Steel Caisson For Inclined Pilecap Of Beitstadsund Bridge In Norway,
2023
Sichuan Road & Bridge (Group) Co., Ltd., Chengdu, Sichuan 610072, China
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 …
Study On Correction Method Of Cable Length Error In Construction Control Of Cable ⁃Stayed Bridges,
2023
School of Civil Engineering, Changsha University of Science & Technology, Changsha, Hunan 410114, China
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 …
Analysis Of Mechanical And Deformation Characteristics Of Karst Tunnel Structure And Research On Treatment Technology,
2023
1. Guangxi Beitou Traffic Maintenance Technology Group Co., Ltd., Nanning, Guangxi 530029, China;
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 …
Influence Of Proximity Construction Of A New Pile Foundation On Adjacent Metro Tunnel,
2023
School of Architecture and Civil Engineering, Shenyang University of Technology, Shenyang, Liaoning 110870, China
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 …
Research On Crack And Permeability Characteristics Of Cement ⁃Modified Expansive Soil Under Dry ⁃Wet Cycles,
2023
1. School of Civil Engineering and Architecture, Guangxi University, Nanning, Guangxi 530004, China;
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 …
Study On Influence Of Freeze ⁃Thaw Cycles On Shear Properties Of Fly Ash Modified Saline Soil,
2023
College of Civil Engineering, Northeast Forestry University, Harbin, Heilongjiang 150040, China
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 …
Effect Of Temperature And Light On Characteristics Of Asphalt Emissions,
2023
1. Experimental Teaching Center of Transportation Engineering, Tongji University, Shanghai 200092, China;
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 …
Study On Triaxial Mechanical Properties Of Glass Fiber Reinforced Cement Soil In Short Age,
2023
School of Civil Engineering, Shaoxing University, Shaoxing, Zhejiang 312000, China
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 …
Study On Experimental Application Of Xinjiang Steel Slag In Cement Stabilized Base,
2023
1. Xinjiang Communications Construction Group Co., Ltd., Urumqi, Xinjiang 830016, China; 2. Xinjiang Jiaojian Highway Planning Survey and Design Co., Ltd., Urumqi, Xinjiang 830016, China;
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 …
Research On Cyclic Accumulative Strain Characteristics Of Structured Soft Clay,
2023
1. School of Civil Engineering, Shaoxing University, Shaoxing, Zhejiang 312000, China; 2. Department of Civil Engineering, Hangzhou City University, Hangzhou, Zhejiang 310015, China
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 …
Effect Of Activator On Compressive Strength Of Steel Slag Powder Cement Soil,
2023
1. Shanxi Transportation Construction Engineering Quality Detection Center, Taiyuan, Shanxi 030000, China;
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 …
Experimental Study On Time ⁃Varying Characteristics Of Saturated Water Content Of Granite Residual Soil In Acid⁃Etched Environment,
2023
1. China Communications Fourth Highway Engineering Bureau Co., Ltd., Beijing 100022, China;
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 …
Mechanical Properties And Micro Analysis Of Cement Stabilized Steel Slag Macadam Base,
2023
Hebei Qiancao Expressway Development Co., Ltd, Tangshan, Hebei 063200, China
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 …
Analysis Of Influence Of Moisture Content ⁃Temperature Dual Factor On Mechanical Properties Of Red Clay,
2023
1. The First Engineering Co., Ltd., China Communications Fourth Highway Engineering Bureau, Beijing 10002, China;
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 …
Influence Of Steel Fiber And Polymer Emulsion On Mechanical Properties And Microstructure Of Concrete,
2023
1. Zhongjiao Road and Bridge South Engineering Co., Ltd., Beijing 101121, China;
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 …
Effect Of Nano ⁃Metakaolin On Frost Resistance Of Concrete,
2023
Guangdong Communication Planning & Design Institute Group Co., Ltd, Guangzhou, Guangdong 510507, China
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 …
Traffic Conflict Analysis Of Multila Neexpressway Based On Simulation,
2023
CCCC Second Highway Survey, Design and Research Institute Co., Ltd., Wuhan, Hubei 430050, China
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 …
Risk Analysis Of Highway Nighttime Maintenance Operation Based On Sem,
2023
1. Institute of Safety Science and Engineering, South China University of Technology, Guangzhou, Guangdong 510641, China;
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 …
