bluuebunny/crossref_metadata_2025 huggingface dataset:
Construction Simulation Analysis and Application of Attached Lifting Scaffold in the Structure with Inward Retraction of Super High-Rise Building
Authors: Li Jiachen , Ou Yazhou , Huo Yaodong , Wang Long , Chen Yunfei
Published: December 2023

Attached lifting scaffold (referred to as climbing frame) is an important construction technology in the field of super high-rise construction. Especially since the beginning of this century, the domestic construction technology of attached lifting scaffold has been rapidly iterated and developed. It changes the high operation into the low operation, and the hanging operation into the internal operation of the frame, which has the characteristics of economy, safety, convenience and so on, and the low carbon benefit is also more significant. The all-steel fire-proof full-protection intelligent lifting platform is used as the external protection frame of the standard floor of the building in Suzhou Huamao Center project area C project. Due to the sky garden set up in building 3# and building 5#, there is a structural retraction in some floors of building 3# and building 5#, resulting in the normal installation and lifting of the conventional climbing frame unavailable. To solve this problem, special columns can be used. This paper mainly focuses on the adhesion measures of the climbing frame at the inward contraction of the structure, studies the construction technology, simulates and analyzes its mechanical performance, summarizes the difficulties in the practice of the technology and gives solutions.
Investigation on Applicability of Common Failure Criteria of Interlayer Staggered Zone Under Unloading Conditions of High Geostress
Authors: Duan Shuqian , Cao Zhongsui , Xiong Jiecheng , Cao Bei , Li Chenyang
Published: December 2023

Based on the experimental results obtained from the undrained triaxial unloading tests of interlayer staggered zone (ISZ), the validity and applicability of five conventional strength criteria are investigated to describe the unloading failure and strength parameters of ISZ through the assessment indexes of the sum of absolute deviation. It is indicated that Mogi-Coulomb criterion has relatively low sum of absolute deviation and Euclidean norm, thus it has a preferable applicability to the description of the strength property of ISZ unloading failure, not only for the stress path of the axial and confining pressure unloading, but also for the course of loading axially and unloading of confining pressure. Considering the influence of the intermediate principal stress and the non-linearity of the Parabolic criterion with relatively high sum of absolute deviation and Euclidean norm, it is more complicated to calculate the derivative with less applicability. Mohr-Coulomb criterion may not be favorable to fit experimental results under higher confining pressure, and hence not be the best choice. Hoek-Brown criterion and Drucker-Prager criterion need to be carefully considered as the two criteria tend to cause the regression result to lack fidelity and cannot describe the strength property of unloading failure of ISZ. Although the above five strength criteria seem to be with high correlations (R2 ≥ 0.95), the fitting deviations vary widely. Therefore, the correlation coefficient does not fully demonstrate the reliability of the criteria, which is suggested to combine with the least sum of absolute deviation to evaluate the applicability of unloading failure criteria of ISZ. The research lays the foundation for the selection of the plastic potential function and the solution of partial differential equations in the follow-up research.
Numerical Analysis of Reinforced Soil Considering Ground Water
Authors: Hai Dapeng , Zheng Jie , Wang Dan , Zheng Zhineng , Lin Mengyu , Wang Xiaoqiang
Published: December 2023

Moisture has a great influence on not only the strength and deformation characteristics of soil, but also on the friction coefficient of interface between filler and reinforcement, thereby on the performance of the reinforced subgrade structure. In this paper, seep/W software is used to analyze the internal water distribution law of reinforced soil retaining wall under different groundwater levels, and then sigma/W software is used to analyze the deformation characteristics of reinforced subgrade structure under water field distribution. The results show that with the decline of groundwater level, the volume moisture content of each part in the vertical direction of reinforced subgrade structure changes greatly, and the moisture content at the bottom of the wall redistributes, and the closer it is to the bottom of the wall, the denser the moisture content distribution is; When the buried depth of groundwater is greater than 8m, the groundwater level has little influence on the performance of reinforced subgrade structure, and the influence of groundwater can increase the lateral deformation of reinforced retaining wall by more than 20%. Groundwater condition and rainstorm condition should be considered in the design of reinforced subgrade structure in order to reflect the influence of water on the performance of reinforced structure and to ensure the safety of reinforced structure.
Traveling Wave Solution to Filtration Model in Porous Medium
Authors: Kuzmina Liudmila , Osipov Yuri
Published: December 2023

Suspension and colloid filtration in porous rocks is encountered in problems of underground hydromechanics associated with construction. The formation of grout sediment in the pores of loose rock increases the water resistance of the soil and strengthens the foundation. A one-dimensional model of filtration in a porous medium considers the particles transport by the flow of a carrier fluid and the deposition of particles on the framework of a porous medium. The purpose of the work is to study the concentrations of suspended and settled particles of a suspension over a long time. Exact and asymptotic methods are used to obtain a solution to the model. The exact solution is presented in an implicit integral form. A set of solutions in the form of traveling waves with an arbitrary initial condition and their asymptotics are constructed. An explicit second-order asymptotic solution for a long time is obtained as an expansion in decreasing exponents. Comparison of the asymptotic solution with the traveling waves makes it possible to choose a single traveling wave corresponding to the exact solution. The closeness of the traveling wave to the exact solution of the filtration model is verified numerically. The traveling wave found determines the explicit asymptotics of the concentration of deposited particles for a long time.
Deformation and Failure Mechanism of Anchoring Rock Beam Protective Layer in Large Underground Powerhouse Based on Multi-Index Under Complex Conditions
Authors: Huang Xiaoying , He Zhou , He Jianhua
Published: December 2023

Taking the protective layer of Yebatan anchoring rock beam as research object, aiming at the phenomenon that deformation and failure mechanism of surrounding rock is difficult to reveal under unfavorable factors such as high geostress, strong excavation and multiple faults, based on the excavation design scheme, by means of numerical simulation, deformation and failure mechanism of surrounding rock of protective layer is analyzed from stress, strain and Hoek index. The results show that the maximum principal stress at the observation point of rock anchor beam protection layer increases at first and then decreases with excavation process, and the maximum value reaches 58.3 MPa, surrounding rock is easy to be damaged. Shear failure range of rock mass around cave extends to deep and lower part of rock mass. Plastic shear strain increases at the same part, and damage degree and distribution range on the downstream side are significantly greater than that on the upstream side. Hoek index at the intersection of the downstream side wall and the bottom plate is the largest in the range of 0.42∼0.56, indicating that serious stress type failure may occur in this disturbed area.
Nonlinear Analysis of Stress-Strain of Reinforced Concrete Beam in Ansys Using the Menetrey-Willam Model
Authors: Mestnikov V.V. , Mestnikova I.V. , Mestnikov V.V.
Published: December 2023

This paper presents a study of nonlinear stress-strain analysis of reinforced concrete beam using the Menetrey-Willam model implemented within the ANSYS software platform. Reinforced concrete stands as an indispensable construction material within the realm of civil engineering, and it is of paramount importance to attain a precise comprehension of its nonlinear response to facilitate the design of structures that are both secure and optimally efficient. The modeling of the stress-strain distribution within a solitary-span reinforced concrete beam was meticulously executed through the utilization of the finite element method as facilitated by the ANSYS software package. Specifically, SOLID185 finite elements, in conjunction with the Menetrey-Willam model, were employed to represent the concrete material, while REINF264 finite elements were enlisted for the reinforcement, incorporating a bilinear isotropic hardening model. Subsequently, the computed results were methodically compared to experimental data obtained by F.J. Vecchio and W. Shim. The numerical computations demonstrated a commendable concordance with the experimental observations, with an associated discrepancy of a mere 0.56% in terms of breaking load and a relatively slight deviation of 7.31% with regard to deflection measurements.
Experimental Study on the Influence Range of Vibroflotation Device Encryption
Authors: Ding Peng , Liu Zhiguo , Mao Hui , Li Menglin , Jiao Zhichao , Kou Weifeng , Lin Peng , Deng Zhiyun
Published: December 2023

In order to study the influence range of vibroflotation device (VD) on the formation during vibroflotation pile densification, based on the physical model test of vibroflotation pile, the relationship curve of the main key construction control parameters during vibroflotation densification was established. The analysis showed that: under the test conditions, the main influence range of the VD on the surrounding soil pressure and acceleration was about 1r in the horizontal direction (r = VD radius), and about ± 2r in the vertical direction. The influence on pore water pressure in surrounding soil was about 2r in horizontal direction and ± 3r in vertical direction. In the process of densification, the pore pressure concentration in the soil around the VD had a certain delay compared with the increase of current intensity, which was manifested as the delayed accumulation effect of pore water pressure in the vibroflotation densification. The peak acceleration was 1r ahead of the peak current intensity, which showed the effect of vibroflotation pre-densification. The research conclusions could provide useful reference for the design and construction of vibroflotation piles.
Effect of Microbial Stabilization on High, Intermediate and Low Compressible Clay
Authors: Sekharan Hridya K , Adil Muhammed , Musammil K M , Vijayakumar Kalyani
Published: December 2023

Engineers may have to construct structures on sites having expansive soil. By treating the soil with admixtures such as cement, bitumen, plastic, etc. Soil stabilization improves strength characteristics such as bearing capacity and unconfined compressive strength. The conventional approaches are time-intensive and are not economically viable. Through the utilization of the Microbial-Induced Calcite Precipitate technique (MICP), microbes have recently emerged to be known as a component that significantly improves the characteristics of soil. It is economical and environmentally friendly. They work on the soil to increase compaction by reducing water absorption and minimizing the void spaces between soil particles. The stabilization of soil takes place by the process of bio-cementation and bio-clogging. Calcite precipitated at the void spaces when the cementation reagent and bacterial solution were introduced to the clayey soil in various proportions. Improvements in density and strength of clayey soil are studied using Bacillus subtilis bacterium concentrations of 1 x 107 cells/ml, cementation reagent composed of urea and calcium chloride (0.5M, 1M, 1.5M, and 2M), and treatment intervals of (7, 14, and 28 days). An unconfined compressive strength test was used to evaluate the optimum bacterial solution concentration, cementing solution molarity, and treatment duration. Maximum strength improvement ratios among the three different expansive soils were also studied. SEM analysis is carried out for the optimum combinations in the three types of soil to confirm the presence of calcite. Hence, an attempt is made to research how bacteria affect the strength of high, intermediate, and low-compressible clay.
Performance Evaluation of Nano TiO2/SBR Composite Modified Asphalt Emulsion and Its Micro-Surfacing Mixture
Authors: Zhu Zhenxiang , Fan Liang , Wang Lin , Li Yongzhen
Published: December 2023

This paper investigated the preparation process and performance of nano-TiO2 and SBR composite modified emulsified asphalt, as well as its application in micro-surface treatment. The experiment results suggest that incorporating 2% nano-TiO2 into emulsified asphalt can improve its viscosity and high-temperature performance, decrease residue normal force, enhance construction characteristics, and boost bonding performance. This paper optimized and determined the dosage range of composite modified emulsified asphalt based on the MS-2 micro-surface treatment grade, and evaluated the cohesion, wet wheel wear and load wheel wear of the micro-surface. The findings indicate that the emulsified asphalt, which has been modified with composite materials, exhibits a rapid dewatering rate and high early strength of the mixture. This allows for an earlier opening of traffic without compromising the final strength or overall technical performance indicators compared to unmodified mixtures.
Experimental Study on Strength Characteristics of Soil-Rock Mixture Under Different Water Contents
Authors: Liu Shunqing , Wen Chuan , Cheng Peiyu , Zhang Zhichao , Wu Zhongteng
Published: December 2023

In order to analyze the softening properties of the strength of soil-rock mixture under different water contents, two different types of soil-rock mixture were selected to study the strength characteristics of soil-rock mixture under different water contents by indoor direct shear test. The results show that the cohesion of soil-rock mixture generally decreases with the increase of water content under the same VBP. When the VBP is small, the internal friction angle of soil-rock mixture decreases with the increase of water contents, but the relationship between the internal friction angle and water content of soil-rock mixture becomes ambiguous when the VBP is high. The shear displacement and shear stress relationship curve of each soil-rock mixture sample is approximately hyperbolic. Under the same volumetric block proportion conditions, the shear stress of soil-rock mixture decreases with the increase of water contents. The research results provide calculation parameters for the stability evaluation of soil-rock slopes, which have practical engineering significance.
The Role of Fine Ground Limestone Powder on Tensile Ductility of HTPP-ECC
Authors: Felekoğlu Burak
Published: December 2023

In this study four different fiber reinforced composites have been prepared with different fine ground limestone powder (FLP)/ cement (C) ratios as 1/1, 1.5/1, 2/1 and 2.5/1, respectively. HRWR admixture and HTPP fiber dosage were kept constant for all mixtures. The W/C ratio was in the range of ∼0.50–0.55. Cement paste volume has been decreased by increasing FLP/C ratios. Fresh state characteristics of ECC mixtures such as the marsh cone flow times of matrix phases (without mortar) and spread-flow diameters have been measured. The uniaxial tensile properties of dogbone shaped specimens have been determined. Tensile stress-strain curves plotted and the crack pattern photographs at definite strain values (0–4%) were captured. Results showed that there is an optimum fine ground limestone powder (FLP)/ cement (C) ratio as 1.5 where tensile ductility of 2.32% can be reached at 4.02 MPa tensile strength without any significant strength loss and fiber clumping problem.
Quantification of the Environmental Effects of Freezing and Thawing in the Yalong River Basin
Authors: Liu Liwu , Wang Song , Sun Qinglin , Ma Chong , Lu Qunfu , Shi Zhenze , Zhou Bingyang
Published: December 2023

In this paper, through the statistics of Yalong River Basin environmental climate data in the past 30 years. Firstly, the statistical method of the number of freeze-thaw times was determined; secondly, the research was carried out from the temperature, solar irradiation, elevation and cooling rate, and the influence on the annual average number of freeze-thaw cycles in the basin was analyzed one by one, and it was found that there was a good correlation between the temperature, solar irradiation and elevation and the number of freeze-thaw cycles; finally, the average atmosphere temperature of the coldest month and the average irradiation of the unit elevation were selected for regression analysis, and the quantitative model of the number of freeze-thaw cycles in the basin was obtained. Finally, the average atmosphere temperature of the coldest month and irradiance per unit elevation were selected for regression analysis, and a quantitative model of the freeze-thaw cycle in this basin was obtained, which is more practical and has higher prediction accuracy than the traditional model, and can better guide the design of concrete engineering in Yalong River basin.
Study on the Evaluation of Water Ecological Security Status of Sanhekou Reservoir Based on DPSIR Model
Authors: Chen Hang , Ma Chao , Wang Ying , Zhou Xiaode , Wang Qianzhou , Zhang Xin
Published: December 2023

This study takes Sanhekou Reservoir as the research area, uses the DPSIR model to construct the water ecological security index system of Sanhekou Reservoir. Analyzing the distribution characteristics and influencing factors of evaluation indicators, and completing the evaluation of the water ecological security status of Sanhekou Reservoir from 2013 to 2021. The comprehensive evaluation results show that the water ecological security evaluation results of Sanhekou Reservoir from 2015 to 2020 were good, and the evaluation results of 2013, 2014, and 2021 were all excellent. The evaluation results of each subsystem also show temporal differences. During the period from 2013 to 2021, the contribution rate of the state index to the water ecological security of the Sanhekou Reservoir Area was the highest, and the evaluation values of the pressure index and impact index in 2013 were much higher than those in 2016. In terms of driving force indicators and response indicators, the changes in the evaluation values between 2013 and 2021 were not significant, indicating that the construction of water conservancy projects has a significant impact on regional water ecological security.
Dam Safety Monitoring and Early Warning Method Based on Knowledge Graph
Authors: Gong Shilin , Sun Futing , Chen Keng
Published: December 2023

Aiming at the problems of monitoring points in the dam with characteristics of numerous and complex spatial relationships, a dam safety monitoring and early warning method based on graph database and aggregation model is proposed. Referring to the knowledge graph element characteristics, the dam monitoring points naming rules were clarified. According to the distribution characteristics of dam monitoring points, the decision rules of spatial adjacency relationship of monitoring points are drawn up, and the dam safety monitoring knowledge graph is constructed. Furthermore, based on the multi-level relationship query capability of the graph database, the correlation response mechanism for monitoring points is established to achieve automatic identification and intelligent grouping of abnormal monitoring points. Finally, an aggregation scoring model for dam monitoring points is proposed to achieve multi monitoring point dam safety monitoring and early warning under the condition of considering the number and spatial distribution of monitoring points comprehensively.
Prediction of Suspended Sediment Concentration by ANN with Immune Genetic Algorithm
Authors: Fan Jinsheng , Luo Qiushi , Bai Yuchuan
Published: December 2023

This paper used the immune genetic algorithm (IGA) for optimizing artificial neural network (ANN) and constructed a new model ANN-IGA to predict suspended sediment concentration(SSC) based on the daily SSC and flow discharge data observed at the hydrological station near Puerto Rico, USA. Moreover, the performances of ANN-IGA were compared with those of ANN with particle swarm optimization (ANN-PSO), ANN, generalized regression neural network (GRNN), radial basis neural network (RBNN) and the traditional sediment rating curve (SRC). The root mean square error (RMSE), mean root square error (MRSE), and coefficient of determination (R2) were adopted as indicators for the evaluation of the prediction accuracy of all models. According to the different settings of the input and output variables, the predictions for four different scenarios were carried out. The comparative analysis results show that we can gain the best prediction results when the current day’s flow is designed as the input variable and the current day’s SSC designed as the output variable for the hydrological Quebrada Blanca station. The MRSE value of ANN-IGA, ANN-PSO, ANN, RBNN, GRNN and SRC is respectively 0.7689, 0.8494, 0.9684, 1.0481, 1.0995 and 1.6742. It is obvious that ANN-IGA and ANN-PSO boast superior performances to ANN, GRNN, RBNN, and SRC. Furthermore, ANN-IGA is slightly superior to ANN-PSO, and ANN is slightly superior to GRNN and RBNN.
Assess Impacts of Well Configuration and Boundary on CO2-Based Geothermal Production Using Response Surface Models
Authors: Chen Mingjie , Al-Hashimi Sulaiman , Al-Maktoumi Ali
Published: December 2023

Geothermal harvest by using sequestered CO2 in underground reservoirs as the working fluid is an effective approach to reduce CO2 emission and fossil energy consumption. The integrated impact of reservoir boundary conditions, well placement and operations on this CO2 geothermal production (CGP) is unclear. This study aims to analyse these influences continuously in a multi-dimensional parameter space, not just several scenarios in the previous studies. A total 200 samples are drawn from a 6-D input parameter space using Latin-Hypercube sampling method. A suite of numerical CGP reservoir models is constructed using the 200 input samples and executed. Five performance outputs are defined and calculated from the simulation results. Response surface (RS) models for each output are developed based on the 200 input-output dataset. Using the fast RS models, sensitivity indices of each output to each input are efficiently calculated to screen sensitive parameters. Pairwise RSs are visualized for evaluation of the impacts of the sensitive inputs on each output. The results show well space is the controlling parameters of the system. Overpressure positively affects CO2 circulation and storage, and heat recovery. Longer horizontal well perforation lengths can enhance CO2 circulation. Boundary conditions won’t affect the system performance except the Y lateral boundaries, which show a positive impact on CO2 storage.
Fuzzy Comprehensive Evaluation Method of Bridge Durability in Freezing Thawing and Chloride Ion Environment Based on Reliability
Authors: Wu Zhijian , Wang Xiangyang , Xie Kaiyue , Xiao Bin
Published: December 2023

Set up a fuzzy comprehensive evaluation method of bridge durability based on reliability. In the freezing-thawing and chloride ion environment, the ultimate and serviceability limit states reflect the mechanical properties of bridge deterioration, the limit states are subdivided into bending limit states and shear limit states, as well as cracking, freezing, and chlorine resistance limit states and limit state equations are obtained based on specifications and literatures; using the Monte Carlo method to analyze local reliability, and the fuzzy evaluation method obtains the reliability index of the bridge systemIn the fuzzy evaluation method, the relative importance of each limit state is analyzed, and the importance judgment matrix of limit state is computed through pairwise comparison. This method is used to calculate and analyze the durability of a prestressed concrete bridge. It shows that the durability of the bridge in the freeze-thaw and chloride ion environment is gradually reduced, and the durability of the bridge is less than 100 years. This method can provide a new reference methodology for bridge durability evaluation.
Evaluation of High Temperature Stability of Asphalt Mixture Improved by Qingchuan Rock Asphalt Based on Accelerated Loading Test
Authors: Guo Hao , Zhuang Chuanyi , Hao Yan , Li Gen
Published: December 2023

The resistance of Chinese Qingchuan rock asphalt to rutting at high temperatures was examined in this paper. Base asphalt, SBS modified asphalt, China Qingchuan rock asphalt modified asphalt (CQRMA), composite modified asphalt by China Qingchuan rock asphalt and SBS modified asphalt (CQR-SBSMA) were created. The high temperature stability of “AC-10C + AC-16C” double-layer asphalt mixture composite rutting specimen was evaluated by 1/3 scale accelerated loading test. The results showed that the dynamic stability of asphalt mixture was increased by about 40% after modified by CQRMA. The time-dependent rutting curve of 1/3 scale accelerated full thickness rutting test is basically consistent with that of constant thickness conventional rutting test, the accelerated loading test can more accurately characterize the high-temperature rutting resistance of asphalt mixture or pavement and its performance attenuation lawThe contributions of different types of as-phalt binders to the high temperature stability of asphalt mixtures were in the order of CQR-SBSMA, SBSMA, CQRMA, and 70-A.
Research on Diagonal Cracks in the Mid Span of Prestressed Concrete Composite Box Girder Bridge
Authors: Zhu Kunning
Published: December 2023

Based on the mid span diagonal crack defect of a reinforced composite box girder on highway, the finite element model is established, the stress distribution in composite box beams under temperature and different live load conditions is analysed, and the changes in shear stress and principal tensile stress before and after reinforcement is researched to analysis the causes of diagonal cracks in the mid span after reinforcement. The results show that the degree of impact of structural stress caused by temperature gradient and vehicle load different before and after reinforcement, and the impact on the edge beam is greater than that on the middle beam. The variation of structural stress before and after reinforcement caused by vehicle load is bigger than that caused by temperature gradient. When the impact coefficient of vehicles and the impact of overloading are considered, after adding mid span diaphragm, due to the reinforcement of the box girder, the principal tensile stress in the edge beam caused by vehicle load is almost 2.9MPa, and this lead to significant risk of cracking. It is necessary to consider the impact of relevant reinforcement measures on the structural stress in the design of reinforcement, especially when the reinforcement plan has an impact on the original stress system of the structure, special attention should be paid to detailed analysis.
Investigation and Treatment for Floor Heave of Highway Tunnels in Gansu Province
Authors: Zhang Gang , Hu Bo , Lu Zhifang , Wu Weipeng , Niu Rong , Liu Guofeng
Published: December 2023

With the increase of tunnel operational time, more and more tunnels have entered the period of high incidence of diseases. Among many tunnel diseases, floor heave is particularly prominent, which seriously affects the traffic and structural safety of tunnels. Through the detailed field investigation of 12 operating highway tunnels of Gansu Province, the main manifestations of floor heave were counted. The floor heave is mainly the result of single or combined action of high ground stress, groundwater, expansive surrounding rock and construction quality. Based on the analysis of the influencing factors of floor heave and the literature research, the common treatment measures for tunnel floor heave disease were summarized. And the application analysis was carried out for the treatment of floor heave disease in Qinlingguan tunnel. The research results have certain guiding significance for the mechanism analysis and prevention practices of floor heave in soft rock tunnel.
Analysis of the Influence of the Stiffness of Vibration Isolating Elements on the Coupled Vibration of Vehicle and Steel Spring Floating Slab Track
Authors: Li Qiuyi , Luo Wei , Wei Yuxuan , Zuo Zhiyuan
Published: December 2023

In order to study the influence of stiffness of different vibration isolation elements on the dynamic performance of steel spring floating slab track of metro, Fuzhou Metro Line 2 is taken as the research object, and based on the combination of online measurement and simulation modeling, the influence law of fastener stiffness and steel spring stiffness on the vehicle steel spring floating slab track coupling dynamic response is analyzed. The research shows that with the increase of fastener stiffness, the vehicle body displacement and rail displacement decrease, and the rail acceleration, track plate displacement and acceleration increase accordingly. The track plate acceleration is most significantly affected by the fastener stiffness, and the acceleration amplitude increases from 4.479 m/s2 to 9.223 m/s2; As the steel spring stiffness increases, the rail acceleration and track plate acceleration will increase, and the vehicle body displacement and acceleration, rail displacement and track plate displacement will decrease. The smaller the steel spring stiffness is, the greater the decrease of the four dynamic response amplitudes mentioned above.
Evaluation of Shale Gas Resource Potential of Carboniferous Dawuba Formation in Southwestern Guizhou Province
Authors: Miao Miao , Wang Chao , Yuan Kun , Chen Xianglin , Lin Tuo , Guo Tianxu , Li Shizhen
Published: December 2023

As a rapidly developing low-carbon energy source, shale gas plays an important role in promoting China’s goal of “carbon peak and carbon neutrality” and ensuring national energy security. Good shale gas was encountered in the Carboniferous Dawuba Formation by Well Qianshuidi 1 and Well Qianziye 1 in southwestern Guizhou province, which confirms the good prospect of shale gas resources in this area. In view of the characteristics of high carbonate mineral content and relatively low siliceous composition in this area, considering the current shale gas exploration status and situation, an evaluation parameter and area selection method featuring “low silicon and high calcium” was introduced to delineate four prospective areas for Carboniferous shale gas in southwestern Guizhou province. In-place shale gas is estimated at 6.37×1012 m3 in the prospective areas, among which 6.11×1012 m3 is distributed outside the ecological protection area. The economic recoverable resources is estimated at 0.62×1012 m3 at a cost below 2 RMB (0.28 USD)/m3.
The Development and Application of a Virtual Simulation Experimental System for Observing the Advanced Abutment Pressure in a Coal Face
Authors: Wu Jingang
Published: December 2023

The research aims to solve the problem pertaining to the field training condition limitation on the observation of advanced abutment pressure of a coal face. To this end, a virtual simulation experimental system for observing the advanced abutment pressure of a coal face is developed by taking an actual coal face in mines as the background. The system developed with C# language shows the B/S architecture and its three-dimensional (3D) model and animation are achieved by applying 3ds Max; the human-computer interaction is realized through Unity 3D. The software system involves five function modules, i.e. experimental introduction, scene navigation, simulation experiment, theoretical examination and experimental report. Through interactive operation, the simulation experiment enables virtual operation training and observation analysis on advanced abutment pressure under various experimental parameters. The monitoring function of the system based on virtual reality (VR) for the ground pressure is extended through the SQL Server database. The development achievement shows practical value in the practical teaching and the system is promising in ground pressure monitoring.
Experimental Study on Seepage Characteristics of Horizontal Well in Porous and Low Permeability Medium
Authors: He Jibin , Feng Jianyue , Zhao Yujun , Zhang Jianwei , Li Xiaojie , He Jin
Published: December 2023

Horizontal well technology is widely used in groundwater, oil and gas exploitation and other fields. However, the permeability characteristics of horizontal wells in low permeability formation need to be further explored. Based on this, according to the field test model, this paper uses the self-designed horizontal well physical model test system, combined with the monitoring of pore water pressure in the process of horizontal well dewatering, real-time collection of groundwater seepage rules in the process of constant head and variable head horizontal well dewatering, The experimental data can be easily obtained: (1) The Internet of things can continuously collect data in real time, and it is convenient to obtain test data; (2) The results show that the pore pressure of horizontal well decreases rapidly before 60 min of variable head dewatering, and then decreases slowly and tends to be stable; In addition, the change of pore pressure in the first half of horizontal well is larger than that in the second half; The horizontal well dewatering in low permeability formation has the phenomenon that the dewatering height does not coincide with the horizontal well wall; (3) From the recharge end to the front end of the horizontal well, the pore pressure changes from large to small and forms a gentle funnel on the cross slope. In conclusion, it can provide a reference for horizontal well exploitation in low permeability formation.
On Mitigation of Damages on Landslide Prone Regions of Uzbekistan
Authors: Abirov Rustam , Miralimov Mirzakhid
Published: December 2023

Inability to guarantee the reliable protection to society lead to risk based approach in provision of protection of infrastructure and human beings. According to the Kyoto Protocol of the UN, one of the priorities for mitigating geological hazards is risk’s management, which includes the development of a set of measures that minimizes the possible damage resulting from the emergence of natural disasters. Successful and competent implementation of the whole range of measures to protect against landslide hazard is an important technical, economic and social aspect of the construction and operation of infrastructure facilities. There are informations about ongoing measures to protect the population, territory and infrastructure due hazards associated with landslides and their consequences is provided in this paper. The whole complex of measures aimed to the solution the engineering tasks of anti-landslide protection are turned into the recognition and assessment of threats, stabilization and retention of the landslide massif.
Research on Intrinsically Safe Power Supply to Large Penetration Distance Radio Wave Penetration Transmitter in Mine
Authors: Li Yunbo , Peng Hongling
Published: December 2023

Radio wave penetration is currently one of the most effective technical means for detecting geological anomalies. With the increase in width of the working surface, the penetration distance of commercially available detection instruments cannot meet the needs of detecting the working surface over 200m. For obtaining a greater penetration distance, it is a difficult task for radio wave transmission technology to further improve the transmitting efficiency and transmit electromagnetic wave signals with stable amplitude. In this paper, the intrinsically safe power supply protection technology, design of intrinsically safe power supply circuit, and protection and testing of intrinsically safe power supply are studied according to explosion-proof standard requirements in GB/T 3836.4. The results show that the intrinsically safe power supply protection circuit is effective in providing protection, with the pulse energy lower than the specified value; therefore, the intrinsically safe power supply meet the explosion-proof requirements stated in the national explosion-proof standard.
Research and Application of Intrinsically Safe Temperature Measurement and Thermal Imager for Mining
Authors: Wang Dongping
Published: December 2023

Based on the demand for temperature detection in coal mines, the types and implementation principles of commonly used temperature sensors were summarized, including DS18B20 digital, PT100 platinum resistance type, distributed fiber optic temperature measurement, infrared temperature measurement type, etc. A thermal imager based on infrared technology has been designed to meet the requirements of non-contact, large area, and continuous temperature measurement, mainly composed of integrated movement, power conversion and isolation circuit, Ethernet switch board, RS485 interface driver circuit, switch input and output interface driver circuit, etc. The hardware design and window material design of the thermal imager were introduced in detail, and the main application scenarios of the thermal imager were analyzed, applied to underground concealed fire source monitoring in coal mines, coal yard temperature monitoring, surface temperature monitoring of equipment, prediction of roof caving and permeability, and monitoring of violations by operators. The actual test results show that the thermal imager has accurate temperature measurement, clear and visible temperature measurement results, and good application prospects.
Road Helmet Wear Detection Based on Improved YOLOv5s
Authors: Wang Chao , Sun Xiaolin , Han Jinxin
Published: December 2023

At present, in order to protect the personal safety of riders, electric vehicle riders wearing helmets has become a mandatory requirement of the traffic control department. In order to improve the supervision of cyclists and protect the safety of cyclists. This paper proposes a road helmet detection algorithm based on improved YOLOv5s. Firstly, the SE attention module is embedded in the backbone network of YOLOv5s to solve the problem that small target detection is easy to miss, and secondly, the C3 residual module of the backbone network is replaced by the lightweight ShuffleNetV2 module to reduce the complexity of the network and improve the speed of target detection and identification. Finally, the network is trained and tested on self-made dataset and compared with the original model detection effect. The experimental results show that the detection precision, recall, and mAP0.5 are increased by 4.5%, 3.6, and 4.1%, respectively, after the improvement, and the improved YOLOv5s model can effectively improve the efficiency and timeliness of EV helmet recognition.
Dynamic Shrinkage Model Design and Frequency Similarity Relationship Verification for Steel Containment of Floating Nuclear Power Plant
Authors: Zhang Chenming , Li Huapeng , Ying Yuchen , Zhang Meng , Liu Hongbing
Published: December 2023

In recent years, with the continuous adjustment and optimization of energy structure, as well as the ongoing promotion of marine power strategies, there has been increasing attention on the technology of offshore nuclear power generation in China. Due to the complexity of the marine environment where the floating nuclear power station is located, the load borne by the containment shell is far more complicated than that of the onshore nuclear power station. Therefore, it is necessary to study the dynamic performance of the containment shell of the floating nuclear power station through experimental methods to ensure the rationality of the containment design. In this paper, the dimensional analysis is based on the similarity second theorem (π theorem), and the dynamic experiments of containment are designed with the scale ratio of 1:10 and the plate thickness ratio of 1:3. The sensitivity analysis of natural frequency is carried out by the distortion series model of design scale and plate thickness, and the similarity criterion of model frequency distortion is listed to verify the rationality of the design of the dynamic experimental model of containment. This study determines the design method of the dynamic experimental model of the containment of floating nuclear power plant, which has application value for the dynamic model design of various complex spherical structures.
Pilot Application of Micropile Foundation in Mountainous Areas in Fujian
Authors: Xiao Dairui , Hang HaiFeng , Hang Pengxian , Dang Bo , Li Chenlei , Wang Hongfei , Liu Ruijun
Published: December 2023

At present, the foundation of mountain transmission lines in Fujian is mostly manually dug foundations, with a depth of up to 10–15m, and there are risks such as poisoning and suffocation in limited space operations, object blows and high falls. In order to reduce the risk in the excavation of foundation pits, the pilot use of mountain micropile foundation in Fujian area, which is a multi-pile bearing foundation with small aperture, uses mountain micro drilling rig to excavate into holes, without personnel entering the foundation pit operation, compared with the traditional manual digging foundation operation, it can effectively reduce the risk of poisoning and suffocation, object blow and high fall in limited space operation.
Impact of Lightning-Induced Wildfires on Power System Based on Satellite Data and Climatological Projections
Authors: Božiček Amalija , Ðurović Marta , Filipović-Grčić Božidar , Stipetić Nina , Franc Bojan
Published: December 2023

The Mediterranean is one of the most cyclogenetic regions in the world. One of the most significant cyclone characteristics that can influence power systems is lightning. Except in the Mediterranean basin, favorable conditions for convection development and lightning appearance can be developed in other warm and moist conditions and in the mountain area. Every season, heavy lightning appears in Croatia, a small Mediterranean country through which the Dinaric Alps stretch. Lightning can cause various damages to the power system network, but also cause wildfire that can lead to additional enormous damages. It is well known that lightning can be very well forecasted by combining different meteorological models and satellite data. Various satellite data can also be used in forest fire monitoring, analysis, and risk prediction. Among the others, fire spreading depends on the vegetation and soil moisture conditions that can also be obtained by satellite. Some climate projections indicate that in the future, it is possible to expect more extreme conditions, more thunderstorms on one side, and more droughts on the other side. Thunderstorms can cause fire development and spread, especially when there is not enough humidity for rain and showers. During the drought, due to soil moisture decrease and vegetation dryness, wildfire spreading becomes easier daily. This paper will present the analysis of lightning-induced wildfires, endangered power system components in Croatia, and a climatic review of wildfires. A method for wildfire protection, vegetation growth monitoring, and post-fire landscape recovery monitoring will be suggested. Conducted analysis and suggested methods can be applied in power system planning and everyday operation through N-k (N-1) analysis. In the analysis, various satellite, meteorological, climatological data, lightning location system, and power system data are used.
A GIS Digital Twin Modeling Approach Applied to Partial Discharge Live Test
Authors: Fang Yizhi , Lin Yuling , Qiu Zicong , Huang Minhua , Li Tianshu , Shen Daoyi , Zeng Dan
Published: December 2023

Gas Insulated Switchgear (GIS) ultra high frequency (UHF) live test presently stands as the most widely employed technique for partial discharge detection in the field. With the ongoing digital transformation of the power grid, the imperative has arisen to advance partial discharge detection toward intelligence and automation. Accordingly, this paper puts forth a digital twin modeling approach for GIS live test, through a comprehensive examination of digital twin technology. This approach encompasses the establishment of a GIS digital twin model, the assessment of both internal and external UHF signals of the GIS, as well as the intelligent guidance for the deployment of UHF sensors, among other aspects. The findings of this study hold significant implications for the maintenance and servicing of GIS equipment.
Investigation on the Aging State Assessment of Transformer Insulation Paper Based on Multi-Feature Comprehensive Assessment Method
Authors: Zhang Liang , Sun Wei , Wei Bing , Wang Yudong , Cheng Song
Published: December 2023

The aging state of transformer insulation papers was not assessed accurately. In this paper, multi-feature comprehensive assessment method was proposed to convert the nonlinear problem into a linear problem fitting for assessing the aging state of insulation papers. The whole aging process was divided into two stages with the degree of polymerization of 500 as the dividing point. The backward multiple linear regression analysis model was established and the error of the fitting results was analyzed. Most of the relative assessment errors were within ± 5 %. It compensated for the deficiency of aging assessment of transformer insulation paper based on single feature, and the accuracy of assessment results was improved.
Performance Analysis of a Carbon Dioxide Transcritical Two-Stage Compression Refrigeration System
Authors: Wei Zhiyong , Wang Jinfeng , Xie Jing , Xu Hao , Wu Chenlong , Ye Guosen , Jiang Jilin , Han Xinrong
Published: December 2023

In this paper, based on the energy analysis method is established across the critical CO2 two-stage compression refrigeration system simulation model. LabVIEW software was used to write simulation programs, and the operation of the refrigeration system under different working conditions was simulated through different parameter Settings. Data analysis of the simulation results was conducted to explore the main factors that affect the COP of the system. The results show that the COP of the system increases with the rise of suction superheat of the compressor. As the evaporation temperature increases, the COP of the system gradually increases. There is an optimal intermediate pressure corresponding to COP
Conceptual Structures in Statutory Interpretation
Authors: Araszkiewicz Michał
Published: December 2023

This paper introduces a framework of conceptual structures allocated to statutory expressions during interpretive heuresis. Drawing from cognitive science research on conceptual structures, the study seeks to enhance existing computational models of legal reasoning across various domains. A comprehensive set of conceptual structures applicable in statutory interpretation is reconstructed. This framework increases awareness of potential interpretive options and contributes to the transparency of legal reasoning.
Automating Business Process Compliance for the EU AI Act
Authors: Novelli Claudio , Governatori Guido , Rotolo Antonino
Published: December 2023

The EU AI Act is the first step toward a comprehensive legal framework for AI. It introduces provisions for AI systems based on their risk levels in relation to fundamental rights. Providers of AI systems must conduct Conformity Assessments before market placement. Recent amendments added Fundamental Rights Impact Assessments for high-risk AI system users, focusing on compliance with EU and national laws, fundamental rights, and potential impacts on EU values. The paper suggests that automating business process compliance can help standardize these assessments and outlines some methodological guidelines.