bluuebunny/crossref_metadata_2025 huggingface dataset:
Lead Contamination in Driver's Blood and Its Effects on Erythrocytes, Leukocytes, and Platelets as A Biomarker
Authors: Mariadi Pra Dian , Lubis Agnes Felicia , Septie Ch Lidwina
Published: December 2023

Lead as a component of air pollution has broad toxic effects and can be detrimental to humans, such as causing abnormalities in kidney function, digestive tract, nervous system, and hematopoietic disorders. Many people carry out their activities on the highway, one of which is an Angkot driver. Drivers who work on the road daily get direct exposure to air pollution, especially from lead (Pb). Therefore they are very vulnerable to the negative effects of lead (Pb). This study aimed to measure blood lead levels as a biomarker of lead contamination in a driving group in Palembang City. The subjects were drivers who had been working for more than 20 years (average 28 years) and the average age was 58 years. Testing blood lead levels using the APHA method and examining erythrocytes leukocytes and platelets using the impedance method and correlation test using the Spearman test. Based on the results of this study, there is a relationship between blood lead levels and erythrocyte (significance: 0.0019) and leukocyte (significance: 0.002) values, but there is no relationship between blood lead levels and platelet values (significance: 0.4), while blood lead levels in drivers are still within the threshold limit (average: 14.9804 µg/L).
Use of information and communication technologies in studying the school course of mathematics
Authors: Turka T.V. , Vertypokh T.O.
Published: December 2023

The article is devoted to the use of information and communication technologies (ICT) in remote mathematics lessons, highlighting the problems of using ICT, highlighting the advantages and disadvantages of using ICT during the educational process, as well as analyzing the results of research on the problems that teachers have when using information and communication technologies in preparation for separate parts of studying mathematics during distance learning.
Google Forms for adaptive testing
Authors: Yozhykov K.I. , Silin E.S.
Published: December 2023

The article discusses the possibility of using the Google Forms web service to create adaptive tests. Recommendations for teachers based on the analysis of the Forms are developed. The logical structure of the adaptive test and the trajectory of testing education applicants are also given.
Haemoglobinopathies: A Review on Statistical Modelling Perspective (Haemoglobinopathies: Statistical Modelling Techniques)
Authors: Angeline J. Kezia
Published: December 2023

Haemoglobinopathies indicate a group of monogenic disorders. The prevalence of Haemoglobinopathies differs based on geographical regions and is higher in tropical countries. Literature has identified that Haemoglobinopathies are higher in tribal and ethnic groups compared to the general population in India. This narrative review explores the methods to analyse data related to Haemoglobinopathies, identifies the research gaps and gains insights on model building and prediction of Haemoglobinopathies. This narrative review includes articles focusing on Haemoglobinopathies, Anaemia and other related disorders, published from 2008 onwards. Full-text and accessible articles found in relevant databases were included. Statistical and a few other techniques like Logistic Regression, Bayesian Modelling, Genetic Risk Scoring, Structural Equation Modelling, Multilevel Tests, Longitudinal Models, Machine Learning Algorithms and Genotyping methods were used to know the risk of acquiring Haemoglobinopathies and to identify important genetic variants. From the findings, it was observed that many studies were conducted to identify the prevalence of Haemoglobinopathies among the general population, but only few in the tribal population. Models based on machine learning algorithms were used for prediction involving haematological parameters and genetic variants, whereas the statistical techniques for prediction include demographic, nutritional, economic, cultural and social indicators.
El relato miniado de extranjería en México
Authors: Perucho Javier
Published: December 2023

Este inventario recopila los libros de minificción que se han publicado en México durante el siglo pasado. Sus autores provienen de América del sur, central y norte, además de escritores nativos de Europa y Estados Unidos cuyas traducciones se consignan para hacer justicia a su labor. A manera de apéndice, en tres tablas se concentra la información correspondiente a editoriales, años de publicación, país y autor.
Thermal Behavior of Old and Recent Façades
Authors: Khatib Milad , Mahmoud Bassam
Published: December 2023

Losing heat additionally results in greater energy expenses and waste of resources. In any construction building, the façades ensure the heat transfer between the exterior and the interior surfaces of the structure. The thermal transfer of a façade is dominated by conduction. This exchange makes them responsible for guaranteeing thermal comfort to the occupants. Uninsulated outside walls can cause substantial heat loss, particularly during the winter. The heat is able to pass via such façade, leaving it hard to keep the appropriate temperature inside the construction. Furthermore, there is traditional outside insulation that uses isolative boards, which come in a variety of materials. They require a coat of render on top to provide additional protection from the outdoors as well as a beautiful finish. Impermeability and additional costs are the main disadvantages of such systems. In recent façades (rainscreens), the use of ventilated or unventilated cavities influences the thermal resistance. The rainscreen tends to have lower thermal transmittance than the stone façade. The thermal transmittance of the curtain wall depends on the thermal transmittance of the glazing and that of the mullions/transoms including the spacer of the double-glazing, calculated from a 2D analysis, so the total thermal transmittance will be a weighted average value. Surface or interstitial condensation occurs when humid air touches a surface T less than the dew point temperature; it is less likely to occur in a recent façade than in an old one. The aim of this topic is to achieve an energy comparison between two identical resident structures. The first one was provided with an old façade; however, the other house had a recent façade. The obtained results show an important saving of energy of the recent façade (refund in electricity bills), ensures thermal comfort, reduces embodied carbon, and protects the planet, the atmosphere, and the environment.
Interlocking Elements Application in Concrete Filled Steel Tubular Columns
Authors: Krishan A.L. , Astafeva M.A. , Rimshin V.I. , Chernyshova E.P.
Published: December 2023

A circular cross-section tube-concrete columns (CFSTC) samples study under local compression with initial eccentricity was carried out. Interlocking steel elements were placed in the concrete core in order to increase the strength of eccentrically compressed pipe-concrete columns. They were laid in three rows in the space between the freshly laid concrete upper end and the steel pipe inner surface. Moreover, the interlocking elements lower and upper layers were made in the form of partially truncated tetrahedrons, obtained by cutting the cubes with planes passing through their middle edges into two equal parts. A cubes layer was placed between the truncated tetrahedrons layers so that all the elements were in close contact with each other with their faces. The performed experiments confirmed the interlocking structures ability, due to their high rigidity, to more evenly redistribute concentrated loads transmitted through them. It is shown that the rational geometry selection of the structural interlocking elements and the conditions for their interaction with each other can be an effective method for increasing the structures certain sections rigidity. The 3 layers interlocking elements structure use noticeably changed the pipe concrete columns samples deformation and destruction nature, which led to an increase in the studied samples strength by an average of 11%.
Calculation of the Lining of Construction of the Shallow Subway Tunnel
Authors: Abirov Rustam , Miralimov Mirzakhid
Published: December 2023

The alternative from the normative method for numerical calculating the construction of the lining of the shallow subway tunnel for standard loads are proposed in this issue. The most important drawback of existing regulatory models and calculation methods is the use linear properties of a material. Applying in practice of new materials, new types of reinforcement, including composite materials, require the use of a more advanced approach for calculation and design of newly constructed structures. It is vital when structures is constructed in seismic prone regions, where it is necessary to take into account seismic loads, as well as reserves of the bearing capability of materials. The proposed method is directed to use real loading diagrams of concrete and reinforcement steel specifications. This approach also allows us to trace the deformation’s character of a reinforced concrete structure in each site of it. By applying proposed below approach a more detailed analysis of the stress and strain state of various elements of the structure are shown here.
Study on Seismic Behavior of Prefabricated Shear Wall Structure with External Infill Wall
Authors: Ma Shanshan , Gao Quanping
Published: December 2023

In order to study the influence of external packed walls on the seismic performance of prefabricated shear walls, a 1:3 scale prefabricated shear wall specimen with two layers of prefabricated (PC) packed walls was designed and manufactured. The deformation form, maximum floor acceleration, maximum relative floor displacement and interfloor displacement Angle of shear wall structure under different seismic intensities were obtained by shaking table test, and the mechanical performance of the specimen was further studied by finite element simulation method. The results show that the prefabricated filled wall set in Y direction provides a certain lateral stiffness to the shear wall structure and reduces the structural deformation in this direction. It is suggested to consider its influence on the overall stiffness of the structure in the design of the structure. The wall cracks are mainly distributed in the parts of connecting beams, the corners of door and window openings and the parts of wall limbs, and eventually the bearing capacity is lost due to the concrete fracturing in the parts of wall limbs.
Construction Technology of Eaves System of Imitating Song Dynasty Buckwheat Wood Structure and Concrete Structure
Authors: Su Ziang , Mei Nan , Wan Chao , Wang Yihao , Yang Kai
Published: December 2023

Modern antique architecture is mainly based on reinforced concrete and steel structure. While inheriting the characteristics of traditional ancient architecture, it changes the stress system of traditional Chinese ancient architecture which is mainly composed of wood structure, and takes reinforced concrete structure and steel structure as the frame, making the whole building have classical appearance, superior structural performance and good durability. The Tea Culture Museum building group adopts a large number of Dougong components and wood-concrete structure connection technology, with complex nodes. Through analysis and summary, a series of key construction technologies such as concrete structure, Dougong structure and decoration of large-scale ancient Song Dynasty buildings are formed. Through this comprehensive construction technology, construction safety is ensured, construction quality is improved, and construction progress is accelerated. It has obtained remarkable economic and social benefits, and has important reference and guiding significance for similar projects, and has broad application prospects.
Research on the Characteristics of Mud Film on the Excavation Surface of Slurry Shield Tunneling Based on Transparent Soil Technology
Authors: Liu Yukun , Wang Jiawei
Published: December 2023

To observe the process of grouting diffusion and mud film formation in shield mud film formation test, based on transparent soil technology and optical observation technology, this paper develops a visual grouting test system for slurry shield excavation surface, carries out the sensitivity analysis of slurry shield mud penetration process under different working conditions, records the penetration images of each cross-sectional and longitudinal section, and binarizes the images, explores the influence of different variables on the diffusion morphology and permeation distance of mud, and finally evaluates the mud film formed. The results show that the penetration time, grouting pressure and cutterhead opening rate have significant effects on the permeation distance of the slurry. On the vertical section, the diffusion range and shape of the slurry are limited by changes in burial depth, showing significant differences; Improving the viscosity of the slurry can obtain a good mud film; Under high permeability soil conditions, reducing the grouting pressure and the opening rate of the shield machine cutterhead, increasing the viscosity of the slurry, helps to form a mud skin type mud film.
Research on the Mechanism and Response Measures of Different Types of Slope Catastrophes in a Construction Site
Authors: Gao Shangrong , Gu Sha , Guo Daoran , Sun Jing , Guo Jian , Wu Guangwei
Published: December 2023

Fail mechanism of slope is often affected by its cause, which determines correct and reasonable countermeasures done. Wrong cognition is an important reason of slope failure, which should be emphasized in practice. Based on a construction site with 96 hectare area, slopes of site perimeter and foundation pits of different buildings are analyzed. Using origin and different standards, slopes are classified into different types, whose failure mechanism is presented by engineering geology analysis method combined with numerical one. Different countermeasures are adopted according to the mechanism. Conclusion as following. (1) Slopes within scope of building site are classified into natural slope and artificial slope. The artificial one includes cut slope, foundation pit slope and embankment slope. Natural slope is the most stable. Stability and disturbance scope of cut slope increase with excavation depth. Foundation pit slope is a typical pit-in-pit, whose stability is the poorest. Embankment slope stability is controlled by thickness and height of refilling. (2) Failure of cut and foundation pit slopes caused by excavation often occur accident by stress and strain fields changed by unloading and lateral constraint cancelled, which causes local stress larger than material strength. Local failure expands transfixion, which causes slope overall un-stability. It is typical strength reserve safety coefficients, whose safety control is limiting the weak stratum and disturbance scope. Sliding-resistant pile in this project is required that its length is passed through coal interlayer and reached into foundation base 1–2 times pile diameter. And anchor length is longer than disturbance scope presented by shear strain contour. (3) Failure of embankment slope caused by refilling often occur incident done by filling loading lager than bearing capacity, which results in slope overall un-stability. It is typical overload safety factor, whose safety control is limiting refilling thickness less than critical one allowed by base. The one in this project is 7.7m, within the thickness clay base being safe and embankment slope being stable. These above cognitions can be referred by similar engineering.
Test Study on Pull Out Properties of V-Shaped Steel Truss Connectors in Precast Sandwich Insulated Wall
Authors: Liang Yongduo , Yi Lujun , Fu Sujuan , Zhang Xueyong
Published: December 2023

In recent years, prefabricated buildings have been vigorously promoted and applied widely in China. Precast sandwich core insulation wall is one of the important means to realize building energy saving. This paper studies the pull out properties of a new V-shaped steel truss connector and shear properties. The test results show that: when the anchor depth of the V-shaped steel truss connector is 15mm, 25mm, 35mm respectively, the safety coefficient has reached 9.22, 9.42 and 9.68 respectively. However, the anchorage depth of the inner leaf plate did not increase significantly against the pulling bearing capacity, and brittle failure occurred at the pull rod of the outer leaf plate. The test results show that this kind of wall has high safety factor, and the safety factor even above 9.0, which can fully meet the safety performance requirements of the structure. The research conclusions of this paper can provide reference for relevant theoretical analysis and engineering application.
Application and Prospects of Construction Robots in Building Construction
Authors: Zhai Haobo , Ren Baoshuang , Wang Ling
Published: December 2023

With the continuous advancement of technology and the development of the construction industry, construction robotics has emerged as an emerging building technology and has gradually attracted attention in the field of house construction. Consequently, the application of construction robotics in house construction has become a research hotspot in recent years. The purpose of this paper is to systematically summarize the current application status of construction robotics in intelligent construction in the house building sector. It discusses the development process, technological classification, and future trends of construction robotics in the field. Through a comprehensive analysis of existing literature and research findings, the advantages and challenges of construction robotics in improving construction efficiency, reducing labor risks, and enhancing construction quality are explored. Additionally, future directions and prospects for development are proposed. The conclusion indicates that there is vast potential for the application of construction robotics in house construction. By introducing robotics technology, construction efficiency can be significantly improved, construction costs can be reduced, labor demands can be decreased, and construction quality and safety can be enhanced. This paper serves as a reference for the construction industry and research institutions, promoting the further development and application of construction robotics in the field of house construction.
BIM Information Technology Application in Construction Management Research
Authors: Zou Jixue , Du Rong , Yang Fan , Zhang Fei
Published: December 2023

To improve the application of Building Information Modeling (BIM)+Geographic Information System (GIS) management system in the whole process of building construction application, this paper studied the advantages of BIM+GIS technology in construction management on the basis of the application of information-oriented construction system. The effective cross-border integration of BIM and GIS promoted the basic construction requirements for the development of smart cities as well as provided strong technical and platform support for the implementation of building interior and exterior incorporation. The factors that may affect safety hazards during construction were analyzed and assessed using the Analytical Hierarchy Process to ensure the safety of construction personnel. BIM+GIS technology optimized the various construction phases of a project, improved the efficiency of the construction work and rationalized the use of resources 3D model display. It will contribute to the sustainable development of China’s construction industry, only in this way can the construction industry forever stand in the trend of The Times and not be engulfed.
Exploration of the Application Path of BIM Forward Design in EPC Projects
Authors: Lei Ting , Jiang Ming , Zheng Zhou , Liu Xiangming , Xiao Bing
Published: December 2023

This paper firstly introduces the fit of BIM technology and EPC mode, and points out the impact of digital development on the construction industry, then analyzes the current situation of BIM forward design, including its development hindering factors and the current situation of mostly staying in the stage of design assistance and supplementation, and then discusses the advantages of BIM forward design compared with the traditional two-dimensional design, including the three-dimensional visualization, the complete retention of data and information, and real-time The advantages of BIM forward design over traditional 2D design are discussed, including 3D visualization, complete retention of data information and real-time coordination. Based on the obstacles to the implementation of BIM forward design, it proposes the co-development of BIM forward design and EPC projects, and discusses a number of key issues such as selecting the BIM implementation of the same people, formulating the organizational structure of the design team, taking the standard family of components as the core, and advancing the transfer of design results to the downstream of the industrial chain, and finally initially forms the application path to realize BIM forward design.
Buckling and Post-Buckling Behavior of Steel and Laminated Composite Cylindrical Shells Subjected to External Pressure
Authors: Ghalghachi Robab Naseri , Fazlalipour Neda , Firouzsalari Saeed Eyvazinejad
Published: December 2023

Tanks are commonly used to store various petrochemical products, water, etc., and therefore are considered a strategic infrastructure type and vital for social functions. Tank structural failure can cause significant life and financial losses and severe environmental damage depending on the content material. Thin-walled cylindrical shells can structurally fail in the form of buckling if the loading excessed the bearing capacity of the shells. FRP composites are a relatively modern construction material type. It has high stiffness and a high strength-to-weight ratio; therefore, FRP composites are also used for tank construction in addition to steel material. In this study, the buckling and post-buckling behaviour of steel and laminated carbon fibre composite (CFRP) cylindrical shells with different geometrical properties when subjected to uniform external pressure is studied numerically using Abaqus finite element software and Riks analysis. The results indicated that the buckling load of the shells decreased significantly with increasing the radius-to-thickness ratio (R/t) and radius-to-length ratio (R/L) of the cylindrical shells.
Effect of Hyperplasticizers on the Rheological Behavior of Matrix Mixtures of Construction Castables
Authors: Trubitsyn Mikhail Aleksandrovich , Furda Lyubov Vladimirovna , Lisnyak Viktoria Vladimirovna , Volovicheva Natalya Aleksandrovna
Published: December 2023

The effect of commercially available polycarboxylate ethers as hyperplasticizers in aqueous suspensions α-Al2O3 and matrix mixtures of construction castables has been investigated. The dependence of the apparent viscosity and flow curves of matrix mixtures on the concentration of various types of the same hyperplasticizers has been determined. The dosage of polycarboxylate esters in suspensions was 0.17 and 0.34 wt.% of reactive alumina powder weight. The rheological behavior of the model system was studied using a rotational viscometer. It was found that an increase in the concentration over 0.34 wt.% of hyperplasticizers leads to an increase in the viscosity of high-alumina suspensions. The measured flow curves were satisfactorily fitted with the Casson model. The flowability of all samples of matrix systems was evaluated using a cone shape immediately after preparation of the mixtures and after 30 and 60 minutes of exposure. Matrix mixture deflocculated with polycarboxylate additive PC1701 practically maintains constant flowability for 30 min. When using the other two dispersants, the flowability of the suspension after 30 minutes of exposure decreases by a factor of 1.2.
Obtaining a Sulfur Composite Material Based on Carbonate-Containing Waste
Authors: Yusupova A.A. , Baraeva L.R. , Medvedeva G.A.
Published: December 2023

A significant group of man-made products consists of mineral sludge formed as part of the process of chemical preparation and clarification of water at the energy sector enterprises. Generally, mineral slimes are ultra-dispersed heterogeneous systems that precipitate during subsequent coagulation and dewatering and, under certain circumstances, form solidified structures. The high dispersion and stable chemical composition of certain sludges provide significant prospects for their use as microfillers and hydration activators, as well as for structure formation of composite materials. At the present stage, the principles and practices of construction materials science indicate that cement mortars and concretes are gradually moving from 3-4-component systems towards 6-8 and more component systems filled with modifiers of various functional purposes. Today, chemical additives, complex modifiers and microfillers are an integral part of composite materials. The most promising sludges in terms of the application in complex construction solutions are carbonate sludges from chemical water treatment at power plants. On the other hand, the problem of accumulation of excess sulfur from oil and gas purification in oil-producing regions is long overdue. An attempt is made to combine the solution of foregoing problems and waste disposal in large-scale production – composite materials for construction purposes. Sulfur in such materials acts as a binder, and carbonate containing wastes are introduced into the filler. The proposed technology is meant to comply with the principles of “green chemistry” on the one hand, and, on the other hand, to obtain competitive materials for construction purposes.
Multi Criteria Performance Analysis for Nano-Iron Oxide Modified Asphalt Cement by Using Fuzzy Promethee II
Authors: Alas Mustafa
Published: December 2023

This study aimed to investigate the intermediate and high temperature performance characteristics of asphalt cement (AC) modified by iron-oxide nanoparticles (ION). Moreover, Fuzzy PROMETHEE-II technique was employed in order to evaluate the performance of base and ION modified AC by considering multiple criteria; physical properties, rheological characteristics, durability and economic aspects. Excluding the control sample (base AC); three different blends that contained 1%, 3% and 5% ION by the weight of AC were prepared. By conducting rheological testing procedures, isochronal plots were constructed and rutting and fatigue resistance parameters were evaluated. In addition to rheological properties, physical properties were also investigated under unaged and aged conditions and they were utilised in the Fuzzy PROMETHEE-II analysis. According to the experimental outcomes, the optimum concentration of ION was found to be 1% by the weight of AC at high temperatures and above this concentration the improvement of viscoelastic behaviour was hindered to due agglomeration. In other respects, addition of ION in the AC resulted in degrading of the elastic properties, meaning lower fatigue resistance against cracking. The findings of Fuzzy PROMETHEE-II also demonstrated similar trend of results with minor deviations indicating that, not only considering a single parameter but also as a complete ranking evaluation considering multiple criteria, the findings of the current study were reinforced.
Mechanical Response and Fatigue Life Analysis of Full Depth Asphalt Pavement Structure
Authors: Lu Bensheng , Xu Xizhong , Yang Fan , Wu Wenjuan , Su Chunhua
Published: December 2023

Based on the typical full depth asphalt pavement structure in Shandong Province, the mechanical response of full depth asphalt pavement structure is analyzed by the elastic layer theory to optimize the combination of full depth high modulus asphalt pavement structure. The reasonable layer of high modulus asphalt mixture was determined. And the influence of interlayer bonding state and temperature on the performance of full depth high modulus asphalt pavement were analyzed. The fatigue life of full depth high modulus asphalt pavement, full depth ordinary asphalt pavement and semi-rigid base asphalt pavement was compared. The results show that the use of high modulus asphalt concrete can significantly improve the structural performance of full depth asphalt pavement. The application of high modulus asphalt mixture in middle and base layer is the most reasonable. The interlayer bonding condition and temperature have significant influence on the tensile strain of asphalt pavement structure. The fatigue life of asphalt pavement under high temperature condition is lower, which should be taken into consideration in the design of pavement structure. The calculated fatigue life of full depth high modulus asphalt pavement is obviously higher than that of full depth ordinary asphalt pavement and semi-rigid base asphalt pavement.
Anti-Corrosion Study of Corrosion Inhibitor and Sacrificial Anode on Coastal Reinforced Concrete Structures
Authors: Zheng Huazhi , Liu Wei , Yan Hao
Published: December 2023

In order to improve the durability of coastal reinforced concrete structures, the effects of the mixed rust inhibitors, migrated rust inhibitors, and zinc-based sacrificial anodes on the reinforcement corrosion behaviors were investigated by linear polarizations and electrochemical impedance spectroscopies. Their rust resistance efficiency was also compared by static weight-loss tests, which were under different chloride concentrations and pH values in simulated concrete pore solution. The test results indicate that the anti-rust performance of the migrated rust inhibitor is weaker than that of the mixed rust inhibitor with the same content (1%) and chloride concentration. The anti-rust effect of the zinc-based sacrificial anode is better than that of the rust inhibitor under a higher chloride concentration (0.85mol/L). Under the same test time (1d), anti-rust content (1%) and chloride concentration (0.6mol/L), the rust resistance properties of each reagent are as follows: (Neutral environment) Zinc-based sacrificial anode < Migrated rust inhibitor < Mixed rust inhibitor, (Alkaline environment) Migrated rust inhibitor < Zinc-based sacrificial anode < Mixed doped rust inhibitor.
Evaluation of Seismic Performance of Rectangular Recycled Aggregate Concrete Columns Under Different Influencing Factors
Authors: Ma Haoran , Peng Sheng , Zhu Yide , Luo Siyu , Zhou Man , Han Yunfei
Published: December 2023

To investigate how different factors affect how seismically robust rectangular columns composed of recycled aggregate concrete perform, data from 53 such columns were systematically analyzed. Through systematic screening, we tracked the displacement and load values at every characteristic point during both forward and reverse loading. After analyzing the selected parameters using the univariate method, it has been discovered that a reduction in the specimens’ load-bearing capacity can be caused by both an increase in the replacement ratio of recycled coarse aggregate, slenderness ratio, and a decrease in the axial compression ratio, the recycled aggregate strength, but an improvement in their ductility performance. The specimen’s bearing capacity rises as the rate of longitudinal reinforcing does. However, the ductility performance initially rises before falling. To ensure the bearing capacity and ductility performance of the specimen, it is advised that the replacement rate of recycled coarse aggregate be between 0 and 30%, the slenderness ratio be between 6.65 and 8.24, the axial compression ratio be between 0.2 and 0.4, and the strength of recycled aggregate concrete be C40 or C50 when designing a rectangular recycled aggregate concrete column for seismic purposes.
Laboratory Investigation on the Effect of Warm Mixing Agent on Low Temperature Performance of Base Asphalt
Authors: Liu Shaopeng , Yue Fuqing
Published: December 2023

The properties of asphalt materials have a significant impact on the quality and performance of road surfaces. Asphalt materials are the main factor affecting low-temperature cracking of road surfaces. The low-temperature performance of asphalt and asphalt mixtures has a significant impact on the quality and service life of road surfaces in northern and central China. SHRP research results suggest that asphalt contributes 80% to the cracking resistance of asphalt pavement. Low temperature cracking is one of the main diseases of asphalt pavement, which is more common in northern China, especially in cold regions and areas with significant daily temperature fluctuations. Cracks will bring many accompanying diseases, such as looseness, erosion, and potholes. At present, the focus is still on considering high-temperature performance indicators, and there is still insufficient consideration for low-temperature cracking of roads in cold regions of China at the asphalt level. There are still serious deficiencies in the evaluation methods and selection of asphalt and asphalt mixtures in low-temperature areas, with a large number of modified asphalt not being evaluated. There is still a blind spot in the understanding of various influencing factors of low-temperature performance (such as type of modifier, Content of modifier, additives, etc.), resulting in problems in engineering application and higher maintenance costs in the later stage. This study mainly used BBR experiments to study different modified asphalt binders, focusing on the base asphalt and studying the influence of warm mix agents Sasobit and SNJ on the low-temperature performance and other properties of asphalt. Finally, based on the low-temperature performance of each modified asphalt, conduct an overall evaluation and comparison, and provide recommendations for the design of asphalt pavement materials.
Carbonation Property of Concrete Prepared by Microorganism Supported on Coral Reef
Authors: Dong Ya , Liang Anquan , Shu Wei , Zhang Zejiang , Zhou Zhihui
Published: December 2023

The crack of concrete will seriously affect the stability and durability of its structure. The microbial mineralization and crystallization technology can effectively improve the crack of concrete. In order to improve the influence of microbial self-healing technology on the mineralization and crystallization of concrete cracks, the South China Sea coral reef calcrete sand was used as a new porous material to support Pasteurella. The microbiological mineralized products were analyzed by SEM-EDS. The results showed that the microbiological mineralized products were mainly calcium carbonate crystals. The carbonization test was carried out to verify the repair effect of the resin on concrete cracks. The results showed that the content of bacteria carrier should not exceed 10%. When the bacterial carrier content is 10% and the mineralization reaction product content is 3%, the carbonization resistance of cement mortar specimen is improved most obviously. This research provides help for the engineering application of concrete crack repair and has high application value.
Study on the Construction of Early Warning System for Reservoir Flood Discharge in China
Authors: Qi Bo , Du Zhenhan , Zhang Shichen
Published: December 2023

To effectively respond to unforeseen events like dam breaches and to mitigate potential disasters resulting from downstream flooding that threatens human lives and property, a thorough analysis and research of the reservoir flood warning system are crucial. This article delves into the current state of reservoir flood management in China, marked by insufficient emergency warning infrastructure, incomplete flood warning systems, and irregular emergency response practices. It conducts a comprehensive examination of China’s regulatory standards and practical implementations, encompassing the construction of the flood warning system, the delineation of responsibilities for managing flood impacts, and compliance with local regulations. Furthermore, this article offers a comprehensive summary and analysis of the existing reservoir flood warning systems in countries such as Switzerland, Japan, the United States, Australia, and the Netherlands. Drawing upon international experiences while considering China’s unique circumstances, the article presents a set of recommendations aimed at fortifying the reservoir flood warning system, advancing the development of flood warning facilities, increasing awareness and readiness for flood warnings, and standardizing the management of downstream flood channels in China.
Study on the Hydraulic Characteristics in the Forebay of Inverted Siphon
Authors: Zhang Jiasheng , Wang Zhigang , Zhang Hongwei , Hu Shun
Published: December 2023

The inverted siphon is a common hydraulic structure used in large-scale, long-distance water conveyance projects. Due to the limitations of terrain, landform and geological factors, the dimensions of the forebay of the inverted siphon are often limited. In order to evaluate its influences on the hydraulic characteristics in the forebay of inverted siphon, a physical model with the Froude scale of 1:30 for a forebay of inverted siphon in Guangdong Water Resources Allocation Project around the Beibu Gulf was established and corresponding tests were conducted. The results show that limited space for the forebays may easily cause insufficient energy dissipation and then the entrainment of air bubbles into the siphon pipes, especially when either the discharge or the water level in the forebay covers a relatively large range in the normal operation. However, the scheme of the twin sills plus twin porous plates can effectively restrict the influencing scope of the hydraulic jump and largely reduced the fluctuation of the water surface at the low water level, which can eventually prevent the air bubbles from entering the siphon pipes.
Design and Construction Technology of Steel Trestle in Jiansha River
Authors: Zhou Longwei , Ye Dian , Li Jinxue , Wang Xusheng , Li Zhengsheng
Published: December 2023

In the pipeline construction, the pipeline installation needs to cross the Tsim Sha River [1], which is obstructed by the river. The Steel Trestle Bridge crosses the Tsim Sha River. The width of the river is 15 m, the water depth is 6 m, and the flow speed is fast. The bridge piers are to be installed on both sides of the river, the single span of the steel trestle is 30 m, which is parallel to the pipeline to be built. The upper structure of the steel trestle is Bailey Beam, and the lower structure is gravity abutment with enlarged foundation, in order to meet the need of pipeline installation and material transportation, temporary steel trestle is erected on the road. This paper mainly introduces the design and construction technology of the steel trestle bridge built on the Tsim Sha River, which provides some practical reference for the construction of the same type of steel trestle bridge [3].
Investigation of Asphalt Raveling: A System Dynamic Approach
Authors: Tokdemir Ömer , Alas Mustafa , Bolouri Farhad
Published: December 2023

One of the factors affecting the quality of life of the citizens is the condition of the city roads; therefore, the asphalting of the roads is one of their basic needs as a facilitator of the citizens’ passage. In this research, an attempt was made to model asphalt wear with a system dynamics approach and predict it for the future based on different parameters. Modelling was done and the result was with a 25% decrease or increase in the initial raveling, the rate of raveling has decreased or increased between 5% and 10%, which shows that the initial raveling is an important parameter in the rate of raveling. In the design and construction of roads, special attention should be paid to initial raveling. Therefore, it should be noted that when negative scenarios happen, they have a greater impact and cause more deterioration. In addition, due to the fact that in this modelling, more formulas are used and it is also data-oriented, the current model can be used for different regions in different countries, provided that the data and items used in the formulas (such as asphalt standards, etc.) are entered into the model based on the conditions of the studied area.
Comparative Study on Consolidation Characteristics of Municipal Sludge After Chemical Conditioning from Different Sources
Authors: Lyu Chong , Zhan Xinjie , Li Zhenya , Xu Xiaolong , Zhu Qunfeng
Published: December 2023

The output of municipal sludge in large and medium-sized cities in China has increased year by year, which results in the dilemma of having no remaining land for sludge to filling. Therefore, it is urgent to reduce the amount of sludge storage in stock. “Chemical conditioning combined with vacuum preloading” is an effective in-situ treatment method for sludge reduction, but the properties of sludge from different sources and different sewage processes vary greatly. Besides, the existing research lacks systematic analysis of the consolidation and permeability properties of different types of municipal raw sludge and conditioned sludge. In this paper, different inorganic salts (Fe3+, Ca2+, Mg2+, Al3+) were selected to carry out chemical conditioning from different sources, and the influence of chemical conditioning on the consolidation characteristics of municipal sludge from different sources was studied. The test results show that the sludge with different pre-treatment process has a great influence on the consolidation and drainage characteristics of sludge. Shanghai municipal sludge using first-level enhanced coagulation process has the worst performance in consolidation and permeability characteristics. On contrary, sludges with A2/O process have the best performance of them. Fe3+ salt and Al3+ salt could improve the dewatering characteristics of different types of sludge, while Mg2+ salt and Ca2+ salt had weak effects. In addition, the specific resistance of Shanghai sludge after 10% FeCl3 conditioned decreased from 1.24×1011m/kg to 2.13×109m/kg, and the consolidation coefficient increased by 13.5–101 times.
Technological Aspects of Laying Recultivation Material in the Excavated Space of a Quarry
Authors: Lolaev Alan , Oganesyan Aleksan , Badoev Aleksandr , Dziov Batraz
Published: December 2023

During the development of underwater quarries, it is important to ensure that during excavation of the soil and subsequent reclamation of the excavated space, a smooth and flat bottom is created. In this regard, a developed technological regulation for underwater laying of reclamation material in the excavated space is presented in this work, which eliminates the resuspension of bottom sediments. The process begins with careful excavation and once the excavation is complete, the next step is to lay down the reclamation material in a manner that minimizes disturbance to the water column and sediment layer. The regulation emphasizes the need for precise control and monitoring of the placement of the reclamation material. The focus of this technological regulation is to promote sustainable and environmentally responsible practices during the development of underwater quarries. By creating a smooth and flat bottom through the proper laying of reclamation material, the potential negative impacts on the surrounding aquatic environment can be mitigated, ensuring long-term ecological balance in these underwater mining operations.
Identification of Resistance Coefficient of Heating Pipe Network Based on Differential Evolution Algorithm
Authors: Liu Zhuangkuo , Zhou Enze , Yu Junli
Published: December 2023

Accurately determining the resistance coefficient of a pipe network under operational conditions is a crucial step in constructing an accurate hydraulic model. In heating systems, the limited number of measurement points poses a challenge, as the identified resistance coefficient of each pipeline may be expected. A resistance coefficient identification scheme based on the Differential Evolution algorithm (DE) is proposed to address this. Through simulations of a real pipe network, it is observed that the resistance coefficients identified by DE exhibit an approximately normal distribution. Building upon this observation, the proposed scheme generates an optimal solution set through multiple runs of the DE. The final optimal solution is then deduced based on the characteristics of the normal distribution. An actual pipe network with 14 thermal inlets is employed to validate the scheme’s feasibility. It is found that the identification process can be terminated after 1088 runs of the DE. The absolute relative error between the calculated and observed flows remains below the impressive threshold of 1%. These results prove that the scheme can significantly improve the stability and uniqueness of the resistance coefficient identification results.
Effect of Escalator Operation Mode of the Deep Subway Escalator During Different Passenger Flow on Evacuation
Authors: Chao Xudong
Published: December 2023

A For studying the impact of three heights of ignition sources at the bottom, middle and top on the impact of urban utility tunnel evacuation, a city utility tunnel was used as a prototype, and a fire model was established using FDS simulation software to analyze the fire of the three high ignition sources on the utility tunnel, the influence of personnel evacuation indicators, and the setting of Smoke barrier to optimize the fire protection structure of the tunnel to analysis of the distribution of CO concentration and visibility before and after the fire optimization of the tunnel. The results show that, compared with the other two ignition source fires, the fire at the bottom ignition source will be the first to have a CO concentration higher than 500 ppm at the characteristic height of the human eye; no matter how the height of the ignition source increases, there is always only the ignition source at the characteristic height of the human eye The temperature at a distance of about 10 m is higher than 60 °C; the bottom ignition source fire has the fastest smoke spread at the height of the human eye feature. The smoke from the bottom ignition source fire spreads fastest at the height of the human eye, and the area with visibility less than 10 m appears first when the fire occurs 8.6 s; after setting the smoke barrier, the spread of smoke at the height of the human eye feature becomes slower, and the CO in the early stage of the fire is also significantly reduced, which is more conducive to personnel evacuation.
From Text to Structure: Using Large Language Models to Support the Development of Legal Expert Systems
Authors: Janatian Samyar , Westermann Hannes , Tan Jinzhe , Savelka Jaromir , Benyekhlef Karim
Published: December 2023

Encoding legislative text in a formal representation is an important prerequisite to different tasks in the field of AI & Law. For example, rule-based expert systems focused on legislation can support laypeople in understanding how legislation applies to them and provide them with helpful context and information. However, the process of analyzing legislation and other sources to encode it in the desired formal representation can be time-consuming and represents a bottleneck in the development of such systems. Here, we investigate to what degree large language models (LLMs), such as GPT-4, are able to automatically extract structured representations from legislation. We use LLMs to create pathways from legislation, according to the JusticeBot methodology for legal decision support systems, evaluate the pathways and compare them to manually created pathways. The results are promising, with 60% of generated pathways being rated as equivalent or better than manually created ones in a blind comparison. The approach suggests a promising path to leverage the capabilities of LLMs to ease the costly development of systems based on symbolic approaches that are transparent and explainable.