bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic mechanical properties of jointed soft rock samples subjected to cyclic triaxial loading: a FEM-DEM-based study
Authors: Liu Mingxing , Liu Enlong , Feng Jili , Zheng Qingsong , Fu Jie , Luo Wenjun 
Published: March 2021

Abstract
In order to investigate the fatigue behavior of jointed soft rock samples with different joint dip angles, cyclic triaxial tests under different stress amplitudes and confining pressures were numerically simulated using the combined finite-discrete element method (FEM-DEM). The dynamic strength and deformation rules were revealed, including the masing effect, the ratcheting effect, the volumetric strain properties and the failure modes influenced by joint dip angles. During the first hysteresis loop, the nonlinearity of the loading curve is much stronger than that in subsequent cycles, and the damage and deformation are almost the most, which demonstrates that the effect of stress history on soft jointed samples subjected to cyclic loading is great, especially the first loading cycle. When the applied static and dynamic maximum deviatoric stress are the same, the vertical compressive stress of the dynamic case is found to be lower than that of the static case, and the vertical tensile stress exists in some local position, which may be the reason why the cracks can increase and propagate gradually when the dynamic maximum stress is lower than the static strength.
Theoretical Analyses and Experimental Research on Transmission of Electromagnetic Wave Passing through Concrete Materials Surface
Authors: Zhou Daochuan 
Published: March 2021

Abstract
Simplified theoretical model of electromagnetic wave propagation on concrete materials surface is established first by only considering the normal incidence case. In order to investigate the impact of concrete component to the wave transmission, concrete materials specimens with different composite were casted, which were tested by electromagnetic pulse testing method. Study shows that the transmission rate is only relevant with the concrete materials relative dielectric parameter. The greater relative dielectric constant, the smaller transmission rate in materials surface is. Among all this concrete casting components, unit volume water content has the most obvious influence on transmission rate. To change the transmission rate of electromagnetic wave, it is necessary to control the unit volume water content in concrete materials design process.
Study on the axial compression performance of partially prefabricated steel concrete columns after fire
Authors: Yang Yong , Yao Xukun , Zhou Pan , Xue Yicong 
Published: March 2021

Abstract
In combination with the advantages of steel reinforced concrete columns, high strength and high performance concrete and precast assembled structures, a new type of partially precast assembled steel reinforced concrete columns (SRHCC) was proposed in this paper. In order to study its post-fire axial compression performance, the finite element analysis software ABAQUS was used to simulate its temperature field under standard fire based on experiments. The results show that the core temperature of the specimen increases with the increase of the thickness of the section steel protective layer and decreases with the increase of the firing time. On this basis, the limit equilibrium theory was used to propose the formula for calculating the residual carrying capacity of SRHCC after fire. The calculated results were close to the test results and tended to be safe.
Seismic Demand Analysis of Stacked Box Structure in Battery Storage Power Station
Authors: Li Sheng , Lu Zhicheng , Zhu Zhubing , Lin Sen 
Published: March 2021

Abstract
The modular construction of building manufactures most part of a building in factories and assemblies the modular units in construction site. It reduces the construction period and has less impact on the environment. The self-supported modular building has been adopted in hotel buildings, hospital buildings and school buildings, et al.. However, due to relatively short history of application, the modular construction has not beenwidely used in multi-storeys industry building. This paper proposed the application of modular structure in electrical installations. In current practice, theenergy storage station installs dozens of modular battery container on ground. When these container boxes are stacked together to form multi-storey structure, land occupation can be significantly reduced. On the other hand, this building manner will make the structural more vulnerable in earthquake. This paper investigated the performance of the structure during earthquakes and found that increasing the structural rigidity under lateral load was necessary. The analysis result also provided suggestion on the shear demand of inter modular connector.
Research on the secondary design of prefabricated buildings based on Three-Dimensional
Authors: Wang Yamin , Li Teng , Su Jizhi , Cheng Nan , Liu Zhong , Wu Hailiang , Zhang Wuchen 
Published: March 2021

Abstract
With the improvement of design requirements and computer technology, the three-dimensional design with multi-professional collaborative design, refined design and engineering digitization as the core, is being popularized and used in the substation engineering design of State Grid Corporation. This paper will use the three-dimensional software to deepen the design of prefabricated buildings, and refine assembly building design, embed pipeline and set openings reasonably, which would reduce the site labor input, shorten the construction period, and reduce the site construction risk, and improve the quality and technological level of engineering construction at the same time.
The Application of Cohesive Element Method in the Stability Analysis of Jointed Slope
Authors: Ma Liangliang , Peng Kai , Ye Xiangfei , Liu Yaolai , Wang Xiaoping , Li Xueyong 
Published: March 2021

Abstract
a coupled numerical method (FEM/DEM) is generated to model the complete fracture processes of rock material. cohesive elements are inserted along the boundaries of the discretized elements to model the fracture initiation and propagation in rock material. Then this method is applied to the jointed slope, and the stability of the slope under different joint cohesion is studied. By comparing theoretical values and numerical results, it is verified that this numerical method can effectively and reliably study the stability of jointed slopes.
Influence of Different Number of the Open Exhaust Outlets in Tunnel Lateral Exhaust System on Smoke Exhaust Effect
Authors: Huang Yang , Zhang Li , Han Xuefeng 
Published: March 2021

Abstract
In this paper, firstly, the parameters of the tunnel fire model are set up, the tunnel model is established, the reasonable grid is divided, and the appropriate fire power is selected. Secondly, the data of exhaust mode, layout position, exhaust power and wind speed of exhaust outlet of lateral exhaust system are selected reasonably. Finally, by using the FDS simulation software, the motion, visibility, smoke spreading distance and temperature of the tunnel fire smoke are simulated by changing the number of smoke vents opened in the lateral exhaust system under the same fire environment. The result of the simulation shows the number of open smoke outlets is 4 groups(upstream 1 group, downstream 3 groups), the smoke control effect is the best.
The hindrances of using modular constructions in Sichuan Province of China: A comprehensive literature review
Authors: Zhou Zhenquan 
Published: March 2021

Abstract
In global construction markets, environmental sustainability plays a significant role in the sustainable development goals (SDGs) presented by the United Nations. To improve building sustainability, an increasing number of investigations have indicated the effectiveness of replacing the cast-in-place building method with modular constructions. However, the practical promotion of modular constructions has been facing various obstacles, especially for those developing countries. This article aims to explore the main hindrances of using modular constructions in the Sichuan Province of China, where the construction conditions are more complicated than other Chinese regions. Through a comprehensive literature review, dozens of previous studies on the barriers of promoting modular constructions outline the critical hindrances in Sichuan’s construction industries. The top five interdependent factors are related to the higher initial costs, insufficient working experiences, high degree of dependency on cast-in-place methods, complexity of stakeholder management, and defective policy support. The research findings can assist in promoting the local modular constructions more smoothly, which can efficiently improve the environmental sustainability of Sichuan under SDGs. To consolidate the research findings and supplement other potential barriers, a formal questionnaire on cultural resistance of ethnic minority groups in Sichuan is required for further investigation.
Settlement Characteristics and Prediction of Weak Expansive Soil Subgrade Based on Track Geometry Measurements
Authors: Huang Qiyun 
Published: March 2021

Abstract
The weak expansive soil subgrade of the railway in operation is prone to settlement in a high-temperature climate, which results in a rapid deterioration in the geometric dimensions of the track, and affecting the safety of the train operation. This paper uses Track Geometry Measurements (TGM) to analyze the deterioration characteristics of track geometry parameters in the subgrade settlement of weak expansive soil. Also establishes a Settlement Prediction Model (SPM) to identify the settlement time of subgrade and predict the value of track geometry parameters before track maintenance. SPM applies to the mileage k285+000∼k300+000 of the weakly expansive soil subgrade section of the Han-Dan Railway. It was verified by the TGM of the 20 subgrade settlement positions of this section. The results show that SPM has a high application value.
Research on Railway Ballast With the Optimal Sphere Filling by Using Discrete Element Model
Authors: Liu Hao , Liu Ganhzong , Wei Xiankui , Liang Chen 
Published: March 2021

Abstract
DEM (discrete element method) is an effective method to study the dynamics of ballast track. The DEM assumes that the ballast is composed of spheres and the optimal combination of spheres in single ballast is the key to study ballast tracks by using DEM. A track ballast model using DEM is established with accurate ballast profile that is filled with spheres obtained by using a binocular 3D scanner and the Bubble Pack algorithm; In this paper, a direct shear test is adopted to study mechanical properties of the track ballast filled differently. The optimal sphere filling method is chosen using a ballast model based on DEM. The results show that: the volume filling rate ω of the ballast is negatively correlated with the radius ratio r of the small ball and the large ball that are adjacent, and positively correlated with the overlap angle ϕ of the two adjacent balls; with the same volume filling rate, the smaller ratio r is, the greater number of spheres is, and the closer the maximum shear stress of numerical calculation is to the measured level; for general engineering calculations, the optimal combination with a volume filling rate of 0.8 should be used for calculation.
Surface Distribution and Sources of Pb content in the ocean current of Jiaozhou Bay
Authors: Yang Dongfang , Lin Dong , Zhang Longlei , Wang Qi , Li Haixia 
Published: March 2021

Abstract
According to the data on the investigation of Jiaozhou Bay in May, August and October, 1992, the Pb content and the horizontal distribution in the surface of Jiaozhou Bay were studied. The results show that in May, in the waters of Jiaozhou Bay, there were three Pb high content sources - open ocean current, ships and wharf, and Licun River. The open ocean current entered Jiaozhou Bay from the bay outside into the bay inside through the bay mouth with a high content of Pb. The Pb content in the mouth of the bay was 20.79 μg/L. In the bay, the ocean current moved forward the shore of the northeast and reached southeast waters of the bay, transporting 5.54 μg/L Pb content. Then, the ocean current continued to move along the nearshore to the northeast and reached the eastern nearshore waters of Jiaozhou Bay. Here, Pb content was transported via ships and wharf and was 16.34 μg/L. After that, the ocean current continued to move along the nearshore to the northeast and reached the waters in the northeast of the bay, with the Pb content 7.09 μg/L. The ocean current continued to move along the nearshore to the northeast and got the coastal waters near the mouth of the Licun River. Here, Pb content was transported via the Licun River and the Pb content was 37.90 μg/L. Afterwards, the ocean current continued to move along the shore to the northeast and reached the waters in the northeast of the bay, carrying 18.27 μg/L Pb content. Then, the ocean current turned westward along the near-shore direction and got the northern waters of the bay, where the Pb content transported via ocean current was 13.72 μg/L. The ocean current continued to run along the shore to the west and got to the westernmost waters in the northwest of the bay. The Pb content transported via the ocean current was 12.84 μg/L. After that, the ocean current turned southward along the near-shore and reached the waters in the southwest of the bay transporting 8.62 μg/L Pb content. At this moment, a low Pb content area of 7.37 μg/L appeared in the central waters of Jiaozhou Bay.
Research on Risk Evaluation of Flooding in Immersed Tunnels During Operation
Authors: Senyang Wu , Peng Cao 
Published: March 2021

Abstract
As more and more immersed tunnels are built in China, due to the characteristics of closed space, long-term structure in deep water, and complicated surrounding environment, if an accident occurs during the operation period, it will cause immeasurable losses. The safety risks faced during the period must also be taken seriously. This paper analyzes the causes of flooding risks and identifies the sources of flooding risks for the flooding risks faced during the operation of the immersed tunnel. Based on the scenario design and simulation analysis, the impact on the tunnel structure at different depths of flooding and the consequences of flooding on immersed tunnels are proposed. Based on this, anti-flooding measures and related suggestions for immersed tunnels during operation are proposed.
Analysis of the trend change in water quality and its influencing factors in Changsha section of the Xiangjiang River
Authors: Lv Zhengze , Huang Guoxian , Zhang Qinghuan , Hu Wei , Sun Xianren , Liu Fuzhen 
Published: March 2021

Abstract
Based on the measured water quality data of national control stations in Changsha city of Xiangjiang River from 2016 to 2019, the principal component analysis method was used to evaluate the water quality at each section. The annual trends in concentrations of ammonia nitrogen and total phosphorus were analysed and the influencing factors were explored. The results show that the water quality of the tributaries of the Xiangjiang River was worse than that of the main stream. The average score of the principal component of Shengli section is the highest, which is 4.412. This suggests that the water quality is poor, where the main pollution sources are domestic sewage and agricultural discharge. From 2016 to 2019, the concentrations of ammonia nitrogen and total phosphorus in each tributary showed a downward trend. The variations of the water quality in each year were mainly affected by rainfall, e.g., the water quality concentration in the dry season was higher than that in the flood season.
The land use pattern and its changes in the upper reaches of the Yangtze River from 1980 to 2015
Authors: Liu Yuting , Xu Jijun , Yao Liqiang , Guo Pengzhe , Yuan Zhe 
Published: March 2021

Abstract
Using the land use data in 1980, 1990, 1995, 2000, 2005, 2010 and 2015 in the upper reaches of the Yangtze River(UYRB), the area and changes of various types of land use in the study area were analyzed, and the transformation characteristics of various land use types were expounded. Suitable landscape indices such as Patch Number(NP), Patch Density (PD), Connectivity Index (COHESION) and Shannon Diversity Index (SHDI)were used to explore and analyze the land use pattern of the study area. The results showed that from 1980 to 2015, farmland, forest and grassland were the main land use types in the UYRB. The area of construction land and grassland increased, the area of farmland, forest, wetland and desert decreased, and the area of lake/river did not change much. The main direction of land use type transfer in the study area was the conversion of farmland to forest, grassland and construction land, grassland to forest, wetland to lake/river, and desert to grassland. Through the analysis of landscape level indicators, it is concluded that the degree of landscape fragmentation in the UYRB in the past 20 years has gradually increased, the heterogeneity of the landscape has gradually increased, and the types of land use have developed towards diversification. Through the analysis of the patch type level indicators in the study area, results showed that farmland, forest and grassland occupied an absolute dominant position in the study area, resulting in a large separation of the rest of the landscape types. The separation of farmland and construction land under the strong interference of human activities, Fragmentation showed a trend of first decreasing and then increasing.
Analysis and assessment on the catastrophe progression evaluation method of slope safety
Authors: Yu Junping , Wu Jiangpeng , Zhu Liqing , Sun Yang , Zhang Chengke 
Published: March 2021

Abstract
Comprehensive assessment of slope safety based on catastrophe theory has been studied and improved in recent years, because of its advantage of simplicity and objective. However, as the evaluation index of slope safety, the result of catastrophe progression has problems on the accuracy and the threshold, and there is no solution available. So the ROC curve (receiver operating characteristic curve), which is commonly used in medical, has been used in the slope engineering for the first time. The ROC curve can intuitively reflect the accuracy of the evaluation method and calculate the threshold of catastrophe progression. Thus, the concept of degree of safety comes forward, which can quantify the safety of slope. The study results of engineering cases show that this method of results evaluation using ROC curve is simple and intuitive, and it plays a good role on the examination of evaluation method. Besides, it can be used as a comparative analysis of different evaluation methods, which provides a new idea for the assessment of evaluation methods of slope safety.
Experimental Study on Wharf yard Foundation Reinforced by Drain Board and Dynamic Consolidation Method
Authors: Yuan Fanglong , Yu Zhifa 
Published: March 2021

Abstract
The intelligent reconstruction project of the old wharf yard faces the problems of soil layer uneven horizontal distribution, hard concrete shell layer on the surface and high groundwater level of the site. Improper treatment can easily induce uneven settlement of the foundation, which will affect the normal operation of the intelligent wharf. Based on the actual project, this paper carries out the experimental research on the dynamic consolidation effect of the foundation with or without the drain board, compares and analyzes the monitoring and detection results of the foundation under two working conditions, and gives the calculation formula of the effective consolidation depth. The results show that: the insertion of the drain board can quickly dissipate the excess pore water pressure caused by the dynamic consolidation construction, and effectively shorten the consolidation time of the soft soil foundation; Compared with the area without drain board, the effect of foundation reinforcement is more obvious in the drain board area, In the range of effective reinforcement depth, it is more conducive to improve the mechanical properties of soft clay layer; Groundwater level is an important factor affecting the effective reinforcement depth of dynamic consolidation foundation, in the coastal areas with high water level, reasonable and effective precipitation measures should be considered; The estimation range of effective reinforcement depth correction coefficient is given, which can provide a reference for the design and construction of foundation dynamic consolidation in similar sites.
Characteristics of a far-dam channel evolution downstream of the Three Gorges Reservoir
Authors: Ge Hua , Deng Chunyan 
Published: March 2021

Abstract
Due to the influence of distance, there is a lag effect of channel erosion and deposition in the far reaches of the lower reaches downstream from the reservoir. In this paper, the scouring and silting characteristics of Wuhan reach in the middle and lower reaches of the Yangtze River after the impoundment of the Three Gorges Reservoir was analysed based on the five times plane topographic data. The results show that although there is some scouring in this reach at the beginning of the impoundment of the Three Gorges Reservoir, the intensity is not large. With the increase of the operation time of the Three Gorges Reservoir, the scour gradually develops to this reach, and the scour intensity increases greatly, but it is still concentrated in the basic channel.
Multi-objective Optimization for Roadway Maintenance Engineering Based on ev-MOGA
Authors: Chen Huilin , Wang Jinmei 
Published: March 2021

Abstract
The performance of roadway maintenance is a highly correlated factor on national socio-economic issues. Roadway maintenance work is a complex task, involving market game, engineering, planning and scheduling. Taking such aspects as quality, schedule and cost into account, this paper develops a multi-objective roadway maintenance system, in which ev-MOGA is adopted to optimize the decisions concerning roadway maintenance. The experimental results can provide a references for fuzzy multi-objective optimization (MOP) problems.
Control of temperature and humidity in geosynthetics test
Authors: Zheng Airong , Fang Yuhang 
Published: March 2021

Abstract
The temperature and humidity of conditioning and test environment are one of the important factors affecting the test results of geosynthetics. The raw materials of geosynthetics are various, and the manufacturing processes are different, so the sensitivity to temperature and humidity is quite different. Determining reasonable temperature and humidity control requirements are of great significance to the quality control of geosynthetics. In order to grasp the status quo of temperature and humidity control in geosynthetics testing, a statistical analysis was carried out on the temperature and humidity control requirements in 55 geosynthetics tests and product standards, and the temperature and humidity control status of 29 laboratories were investigated.
Study on evolution characteristics of a near-dam channel downstream of the Three Gorges Reservoir
Authors: Ge Hua , Deng Chunyan 
Published: March 2021

Abstract
Riverbed scouring and silting is strongly related to flood control, navigation, water intake and so on. Therefore, a deep understanding of the scouring and silting characteristics of the near dam river reach is the premise of the optimal operation of the Three Gorges Reservoir. Based on the four times topographic data of the near dam reach after the impoundment of the Three Gorges Reservoir, the scouring and silting characteristics were studied in this paper. The results show that, after the impoundment of the Three Gorges Reservoir, except for the siltation of deep channel in some years, the other reaches had shown a scouring, and the scouring is concentrated in the low flow channel, and the change of channel above the flat is small.