The purpose of this study is to analyze the application of ultrasonic non-destructive testing technology in bridge engineering.During the research phase,based on literature collection and reading,as well as the analys...The purpose of this study is to analyze the application of ultrasonic non-destructive testing technology in bridge engineering.During the research phase,based on literature collection and reading,as well as the analysis of bridge inspection materials,the principle of ultrasonic non-destructive testing technology and its adaptability to bridge engineering are elaborated.Subsequently,starting from the preparation work before inspection until damage assessment,the entire process of ultrasonic non-destructive testing is studied,and finally,a technical system of ultrasonic non-destructive testing for bridge engineering that runs through the entire process is formed.It is hoped that this article can provide technical reference value for relevant units in China,and promote the high-quality development of China’s bridge engineering from a macro perspective.展开更多
This paper conducts practical research on the application of steel fiber reinforced concrete construction technology in road and bridge engineering.The study emphasized in its core advantages of tensile strength,impac...This paper conducts practical research on the application of steel fiber reinforced concrete construction technology in road and bridge engineering.The study emphasized in its core advantages of tensile strength,impact resistance,fatigue resistance and high toughness,and introduces its applications in scenarios such as bridge deck pavement,expansion joints and tunnel opening sections.The key points of construction techniques such as material ratio and fiber selection,mixing,pouring and vibration,as well as quality control difficulties and solutions such as steel fiber dispersion,shrinkage cracks and temperature control was analyzed.The development trends of intelligent material research and development and automated construction technology,and propose application suggestions for engineering design and construction management was discussed in this study,which can serve as a references to improve the quality of road and bridge engineering.展开更多
The questions of what kind of individuals university education should cultivate,how to cultivate them,and for whom they are being trained are pressing issues that require immediate solutions.Implementing ideological a...The questions of what kind of individuals university education should cultivate,how to cultivate them,and for whom they are being trained are pressing issues that require immediate solutions.Implementing ideological and political education is a fundamental way to address these challenges.Integrating political education into professional courses is just as important as imparting knowledge,fostering interest,transmitting values,and shaping students’character and spirit.The excavation of ideological and political elements in bridge engineering courses should comprehensively consider the dependent subject of ideological and political elements,the source of cases,the depth of excavation,the trade-offs between courses,the commonality and multifaceted nature of ideological and political elements,as well as the two ways of ideological and political elements integration.Ideological and political elements should be integrated into all stages of classroom lectures,course assignments,final examinations,course design,discipline competitions,school-enterprise cooperation,etc.,so as to achieve the effect of educating people in the whole process.展开更多
Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the...Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the construction technology for bridge engineering has evolved,the internal quality of construction has significantly improved.However,the appearance quality remains a crucial factor that reflects the technical expertise of a construction company.Therefore,minimizing cracks and improving the appearance quality of concrete are critical issues that require the attention of construction units,supervision departments,and construction companies.This article will analyze the causes of cracking and suggest corresponding prevention and treatment methods.展开更多
In order to identify the shortcomings and weaknesses of bridge engineering construction quality in Zhejiang province, this paper firstly selects the quality criteriums of four bridge engineering construction quality c...In order to identify the shortcomings and weaknesses of bridge engineering construction quality in Zhejiang province, this paper firstly selects the quality criteriums of four bridge engineering construction quality criteriums, including concrete durability of outbound construction, construction of large steel box girder, construction of large concrete members and prestressed construction, based on the regional characteristics of Zhejiang province. Then, the quality index of construction projects is analyzed by benchmarking projects in the province, and the gap between the application of high-performance steel, the production and installation technology of steel box girder, the construction equipment of marine concrete components, the installation and tension technology of prestressed pipe and the international advanced level is found. On this basis, the paper puts forward the construction quality improvement strategies in three aspects: design concept, industrial construction level and achievement transformation.展开更多
In recent years, the traffic pressure is increasing. It is of great practical significance to effectively relieve the traffic pressure, improve the transportation efficiency and speed up the road and bridge constructi...In recent years, the traffic pressure is increasing. It is of great practical significance to effectively relieve the traffic pressure, improve the transportation efficiency and speed up the road and bridge construction. In the concrete implementation process, not only technical support, but also safety management should be done well, because this is not only related to the quality of roads and bridges, but also closely related to the traffic safety of pedestrians and vehicles. Therefore, based on the problem, this paper puts forward some suggestions for follow-up reference.展开更多
Highway bridge is the key component of infrastructure construction in China. The construction of highway plays a key role in promoting China's national economy. Implementing highway and bridge construction is an u...Highway bridge is the key component of infrastructure construction in China. The construction of highway plays a key role in promoting China's national economy. Implementing highway and bridge construction is an urgent task in China's socialist modernization. Among them, the roadbed and pavement construction technology has a certain influence on the level of road and bridge engineering. On this basis, this paper introduces the key points of subgrade and pavement construction, analyzes the problems in construction, introduces the main construction technologies of subgrade and pavement in detail, and discusses the application measures of subgrade and pavement construction technology, with a view to continuously improve the quality of road and bridge construction projects.展开更多
This paper analyzes on the common diseases of the road and bridge engineering during the construction period, researches on the causes of these diseases, and puts forward some corresponding solutions for these disease...This paper analyzes on the common diseases of the road and bridge engineering during the construction period, researches on the causes of these diseases, and puts forward some corresponding solutions for these diseases, so as to reduce the adverse effects of the road and bridge engineering diseases on the traffic safety problems. The construction treatment technology in road and bridge construction is elaborated and analyzed, so as to improve the construction quality of road and bridge engineering. It provides reference and ideas for improving the quality of road and bridge construction and improving the safety of China's transportation industry.展开更多
The construction of perfect highway and bridge engineering facilities can realize the resource transfer and cultural transmission between regions, and improve the social and economic benefits. Therefore, China attache...The construction of perfect highway and bridge engineering facilities can realize the resource transfer and cultural transmission between regions, and improve the social and economic benefits. Therefore, China attaches great importance to the construction of highway and bridge engineering. Because the construction of highway and bridge engineering is affected by the regional terrain and natural climate, it is bound to face many influencing factors in the process of construction and management, among which the subgrade is one of the most influential factors for highway and bridge engineering. Therefore, it is necessary to fully implement quality control, and explore the meaning and practical value of quality control, which is the basic premise to strengthen the effectiveness of quality management.展开更多
In the current new form of social development, the relevant staff can effectively manage the contracts related to road and bridge construction cost, and put forward the corresponding analysis and countermeasures for t...In the current new form of social development, the relevant staff can effectively manage the contracts related to road and bridge construction cost, and put forward the corresponding analysis and countermeasures for the risks existing in its management center, so as to effectively control the overall construction cost to a certain extent, and at the same time, can also pre-judge the related risks that may occur in the process, so that the overall construction development presents a good development trend. In this regard, the relevant staff must form a comprehensive understanding of the relationship between road and bridge project cost and contract management under the new form, and analyze the risks and measures to a certain extent if they want to effectively achieve the above objectives.展开更多
With the continuous improvement of the production technology level of Chinas construction industry and the continuous development of prefabricated technology, the application scope of the technology is also expanded. ...With the continuous improvement of the production technology level of Chinas construction industry and the continuous development of prefabricated technology, the application scope of the technology is also expanded. In the construction of municipal bridge engineering, the prefabricated technology can be integrated and applied. This technology has obvious advantages compared with the traditional technology. The construction speed of prefabricated buildings is fast and the quality of the construction can be guaranteed, and the project construction meets the requirements of energy conservation and environmental protection. Therefore, it is necessary to analyze the development status of municipal bridge engineering construction and summarize the existing problems. The traditional technology and prefabricated technology are compared and analyzed to understand the construction advantages of prefabricated bridge, and the reasonable application strategies are put forward. Based on this, this paper discusses the application of prefabricated technology in municipal bridge engineering, in order to provide reference for relevant units.展开更多
With the continuous development of highway and bridge projects in China, the scale and scope of construction are constantly expanding, and people have increasingly high requirements for the quality of highway and brid...With the continuous development of highway and bridge projects in China, the scale and scope of construction are constantly expanding, and people have increasingly high requirements for the quality of highway and bridge projects. In order to meet peoples quality needs at this stage and ensure peoples travel safety, it is necessary to constantly strengthen the quality control of the project during the actual construction process, relevant staff should be able to deeply understand the types of accidents that are easy to occur in the construction process. At the same time, they should continue to deal with accidents through thinking about problems, learning from experience and strengthening management, so as to ensure the smooth construction of highway and bridge projects and promote the rapid development of Chinas highway and bridge industry. The article first analyzes the common accidents in the construction of highway bridge engineering, and then focuses on the treatment countermeasures of the common accidents in the construction of highway bridge engineering, which can be used as a reference for readers.展开更多
Road bridge can provide convenient for people to travel, in its construction, related construction units to realize the important role of safety management, accurately grasp the construction key points, innovation and...Road bridge can provide convenient for people to travel, in its construction, related construction units to realize the important role of safety management, accurately grasp the construction key points, innovation and optimize safety management measures, strengthen safety management and quality control, to ensure the smooth construction of the project, maintenance personnel safety, make the project more durable, stable and safe. At the same time, in different regions, we should implement the basic principle of adjusting measures to local conditions and according to current conditions, save construction costs to a greater extent, focus on environmental protection, take more practical measures, so that the overall project can achieve better efficiency, and then provide necessary conditions for the embodiment of the comprehensive efficiency of the project.展开更多
Engineering surveying is an important course for road and bridge engineering technology majors in higher vocational colleges.With the advancement of science and technology,engineering surveying technology is also cons...Engineering surveying is an important course for road and bridge engineering technology majors in higher vocational colleges.With the advancement of science and technology,engineering surveying technology is also constantly developing,so the theoretical knowledge and professional skills that students need to master are also becoming increasingly complicated.To stimulate the students’interest in learning the course,it is necessary to continuously introduce innovative teaching methods into the course.In this paper,the importance of teaching innovation in engineering surveying courses of road and bridge engineering technology majors in higher vocational colleges and the knowledge system that students need to master are analyzed.Subsequently,innovative strategies are proposed to help improve the students’mastery of engineering surveying.展开更多
Bridges may suffer from large-amplitude vibrations due to strong winds,earthquakes,human-induced loads,and vehicle-induced dynamic loads.Metallic dampers employed the energy dissipation from the hysteretic behavior of...Bridges may suffer from large-amplitude vibrations due to strong winds,earthquakes,human-induced loads,and vehicle-induced dynamic loads.Metallic dampers employed the energy dissipation from the hysteretic behavior of metal materials are among the most effective methods to mitigate bridge vibrations.This paper reviews the development and application of metallic-yielding dampers for the vibration control of bridges.Various theoretical models for metallic damper analyses are reviewed.Different yielding mechanisms and manufacturing materials of metallic dampers are discussed.Finally,the recent progress and application of bridge engineering are summarized.It can be concluded that each section of the torsion-type metallic damper exhibits a uniform stress state and undergoes plastic deformation simultaneously.Therefore,the damper has a strong energy dissipation capacity.Additionally,self-centering metallic dampers can automatically recover to their initial position after suffering an earthquake.Combined metallic dampers can take advantage of different types of dampers,thereby enhancing damping performance.Finally,these dampers will significantly enhance the seismic performance and overall safety of bridge structures.Future research will likely focus on hybrid systems that combine metallic dampers with other energy consumption mechanisms to further improve adaptability and energy dissipation,advancing the resilience and safety of bridge structures.展开更多
This article analyzes the application strategies of shotcrete anchor support technology using a highway bridge-tunnel construction project as an example.The article covers various strategies,including support plan for...This article analyzes the application strategies of shotcrete anchor support technology using a highway bridge-tunnel construction project as an example.The article covers various strategies,including support plan formulation,mortar shotcrete anchor construction,grid steel frame construction,steel mesh construction,and concrete support construction.This analysis aims to provide a guideline for those interested in applying this technology and improving the quality and safety of highway bridges and tunnels construction.展开更多
D-p-hydroxyphenylglycine(D-HPG)is an important intermediate in the pharmaceutical industry,and it is commonly syn-thesized by cascading D-hydantoinase(DHase)and D-carbamoylase(DCase).In this study,the stability of DCa...D-p-hydroxyphenylglycine(D-HPG)is an important intermediate in the pharmaceutical industry,and it is commonly syn-thesized by cascading D-hydantoinase(DHase)and D-carbamoylase(DCase).In this study,the stability of DCase was identified as the main problem that limits its application.Therefore,the complexed structure of AkDCase(DCase from the Agrobacterium sp.strain KNK712)with the substrate N-carbamoyl-D-p-hydroxyphenylglycine(CpHPG)(with 2.52Åresolution)and catalytic mechanism were resolved.Based on the catalytic mechanism and electrostatic stabilization,salt bridge engineering was adopted to improve AkDCase thermostability.The best variant,AkDCase^(D30A),increased theTm by 2.91℃and half-life(t_(1/2))at 40 and 60℃by 18.43 h and 23.21 min,respectively.After AkDCase^(D30A) was assembled with GsDHase(DHase from Geobacillus stearothermophilus SD-1)in a single Escherichia coli cell,the recombinant strain could produce 29.53 g/L D-HPG within 12 h,with a 97%conversion and a 2.46 g/(L·h)space-time yield(STY).The titer of D-HPG increased by 40.55%compared to the E.coli cell harboring pETduet-1-AkDCase-GsDHase.The recombinant strain could be used for two cycles.Our research provides a basis for the industrial production of D-HPG.展开更多
To address local concrete damage in joint areas at the footing of prefabricated assembled self-centering bridge piers(PASPs)in seismic design,a damage transfer configuration(DTC)was proposed,based on the bridge pier s...To address local concrete damage in joint areas at the footing of prefabricated assembled self-centering bridge piers(PASPs)in seismic design,a damage transfer configuration(DTC)was proposed,based on the bridge pier structure configuration and the mechanism of local damage formation.Integrating the DTC into the PASP,numerical models of a previous experimental reference PASP and a PASP with damage transfer configuration(DTPASP)were established using the finite element software ABAQUS with a concrete damage plasticity(CDP)model.The models were then compared with experimental results regarding damage distribution,hysteresis curves,energy dissipation capacity,the joint opening degree,and residual displacement.The findings indicate that the finite element model developed in this study can well reflect the experimental results of the reference PASP.The incorporation of the DTC proved to be beneficial in preserving structural integrity,bearing capacity,and the functionality of the core structure of bridge piers following an earthquake.Meanwhile,this addition did not exert a significant influence on the seismic behavior of the core structure of the bridge pier.展开更多
The theoretical design method of enhanced sensitivity fiber grating （FBG） strain sensors was given, and moreover high qualified strain sensors were developed and fabricated, whose sensing properties were good for pr...The theoretical design method of enhanced sensitivity fiber grating （FBG） strain sensors was given, and moreover high qualified strain sensors were developed and fabricated, whose sensing properties were good for practical applications. The strain sensor with cylindrical shell encapsulation contained three tubular structures, due to the uneven surface structure, in the area of the strain concentration, improving the sensitivity. It could achieve the embedment strain measurement and surface measurement and had the advantages of the easy installation. The good agreement was obtained between the measurements and theoretical simulation results. After each calibration test, twenty-four FBG strain sensors and six FBG temperature compensation sensors have been installed on the undersurface of the box girder of Diaoshuiyan bridge in Yongtaiwen highway. Finally, we built up a long-term structure health system for the highway bridge.展开更多
In the realm of high-speed railway bridge engineering,managing the intricacies of the track-bridge system model(TBSM)during seismic events remains a formidable challenge.This study pioneers an innovative approach by p...In the realm of high-speed railway bridge engineering,managing the intricacies of the track-bridge system model(TBSM)during seismic events remains a formidable challenge.This study pioneers an innovative approach by presenting a simplified bridge model(SBM)optimized for both computational efficiency and precise representation,a seminal contribution to the engineering design landscape.Central to this innovation is a novel model-updating methodology that synergistically melds artificial neural networks with an augmented particle swarm optimization.The neural networks adeptly map update parameters to seismic responses,while enhancements to the particle swarm algorithm’s inertial and learning weights lead to superior SBM parameter updates.Verification via a 4-span high-speed railway bridge revealed that the optimized SBM and TBSM exhibit a highly consistent structural natural period and seismic response,with errors controlled within 7%.Additionally,the computational efficiency improved by over 100%.Leveraging the peak displacement and shear force residuals from the seismic TBSM and SBM as optimization objectives,SBM parameters are adeptly revised.Furthermore,the incorporation of elastoplastic springs at the beam ends of the simplified model effectively captures the additional mass,stiffness,and constraint effects exerted by the track system on the bridge structure.展开更多
文摘The purpose of this study is to analyze the application of ultrasonic non-destructive testing technology in bridge engineering.During the research phase,based on literature collection and reading,as well as the analysis of bridge inspection materials,the principle of ultrasonic non-destructive testing technology and its adaptability to bridge engineering are elaborated.Subsequently,starting from the preparation work before inspection until damage assessment,the entire process of ultrasonic non-destructive testing is studied,and finally,a technical system of ultrasonic non-destructive testing for bridge engineering that runs through the entire process is formed.It is hoped that this article can provide technical reference value for relevant units in China,and promote the high-quality development of China’s bridge engineering from a macro perspective.
文摘This paper conducts practical research on the application of steel fiber reinforced concrete construction technology in road and bridge engineering.The study emphasized in its core advantages of tensile strength,impact resistance,fatigue resistance and high toughness,and introduces its applications in scenarios such as bridge deck pavement,expansion joints and tunnel opening sections.The key points of construction techniques such as material ratio and fiber selection,mixing,pouring and vibration,as well as quality control difficulties and solutions such as steel fiber dispersion,shrinkage cracks and temperature control was analyzed.The development trends of intelligent material research and development and automated construction technology,and propose application suggestions for engineering design and construction management was discussed in this study,which can serve as a references to improve the quality of road and bridge engineering.
基金Chongqing Institute of Engineering Ideological and Political Teaching Demonstration Course Construction Project(KC20230010)。
文摘The questions of what kind of individuals university education should cultivate,how to cultivate them,and for whom they are being trained are pressing issues that require immediate solutions.Implementing ideological and political education is a fundamental way to address these challenges.Integrating political education into professional courses is just as important as imparting knowledge,fostering interest,transmitting values,and shaping students’character and spirit.The excavation of ideological and political elements in bridge engineering courses should comprehensively consider the dependent subject of ideological and political elements,the source of cases,the depth of excavation,the trade-offs between courses,the commonality and multifaceted nature of ideological and political elements,as well as the two ways of ideological and political elements integration.Ideological and political elements should be integrated into all stages of classroom lectures,course assignments,final examinations,course design,discipline competitions,school-enterprise cooperation,etc.,so as to achieve the effect of educating people in the whole process.
文摘Cracking during construction is a common occurrence in modern bridge engineering that can directly impact the overall safety of the bridge.Therefore,it is essential to focus on preventing and controlling cracks.As the construction technology for bridge engineering has evolved,the internal quality of construction has significantly improved.However,the appearance quality remains a crucial factor that reflects the technical expertise of a construction company.Therefore,minimizing cracks and improving the appearance quality of concrete are critical issues that require the attention of construction units,supervision departments,and construction companies.This article will analyze the causes of cracking and suggest corresponding prevention and treatment methods.
文摘In order to identify the shortcomings and weaknesses of bridge engineering construction quality in Zhejiang province, this paper firstly selects the quality criteriums of four bridge engineering construction quality criteriums, including concrete durability of outbound construction, construction of large steel box girder, construction of large concrete members and prestressed construction, based on the regional characteristics of Zhejiang province. Then, the quality index of construction projects is analyzed by benchmarking projects in the province, and the gap between the application of high-performance steel, the production and installation technology of steel box girder, the construction equipment of marine concrete components, the installation and tension technology of prestressed pipe and the international advanced level is found. On this basis, the paper puts forward the construction quality improvement strategies in three aspects: design concept, industrial construction level and achievement transformation.
文摘In recent years, the traffic pressure is increasing. It is of great practical significance to effectively relieve the traffic pressure, improve the transportation efficiency and speed up the road and bridge construction. In the concrete implementation process, not only technical support, but also safety management should be done well, because this is not only related to the quality of roads and bridges, but also closely related to the traffic safety of pedestrians and vehicles. Therefore, based on the problem, this paper puts forward some suggestions for follow-up reference.
文摘Highway bridge is the key component of infrastructure construction in China. The construction of highway plays a key role in promoting China's national economy. Implementing highway and bridge construction is an urgent task in China's socialist modernization. Among them, the roadbed and pavement construction technology has a certain influence on the level of road and bridge engineering. On this basis, this paper introduces the key points of subgrade and pavement construction, analyzes the problems in construction, introduces the main construction technologies of subgrade and pavement in detail, and discusses the application measures of subgrade and pavement construction technology, with a view to continuously improve the quality of road and bridge construction projects.
文摘This paper analyzes on the common diseases of the road and bridge engineering during the construction period, researches on the causes of these diseases, and puts forward some corresponding solutions for these diseases, so as to reduce the adverse effects of the road and bridge engineering diseases on the traffic safety problems. The construction treatment technology in road and bridge construction is elaborated and analyzed, so as to improve the construction quality of road and bridge engineering. It provides reference and ideas for improving the quality of road and bridge construction and improving the safety of China's transportation industry.
文摘The construction of perfect highway and bridge engineering facilities can realize the resource transfer and cultural transmission between regions, and improve the social and economic benefits. Therefore, China attaches great importance to the construction of highway and bridge engineering. Because the construction of highway and bridge engineering is affected by the regional terrain and natural climate, it is bound to face many influencing factors in the process of construction and management, among which the subgrade is one of the most influential factors for highway and bridge engineering. Therefore, it is necessary to fully implement quality control, and explore the meaning and practical value of quality control, which is the basic premise to strengthen the effectiveness of quality management.
文摘In the current new form of social development, the relevant staff can effectively manage the contracts related to road and bridge construction cost, and put forward the corresponding analysis and countermeasures for the risks existing in its management center, so as to effectively control the overall construction cost to a certain extent, and at the same time, can also pre-judge the related risks that may occur in the process, so that the overall construction development presents a good development trend. In this regard, the relevant staff must form a comprehensive understanding of the relationship between road and bridge project cost and contract management under the new form, and analyze the risks and measures to a certain extent if they want to effectively achieve the above objectives.
文摘With the continuous improvement of the production technology level of Chinas construction industry and the continuous development of prefabricated technology, the application scope of the technology is also expanded. In the construction of municipal bridge engineering, the prefabricated technology can be integrated and applied. This technology has obvious advantages compared with the traditional technology. The construction speed of prefabricated buildings is fast and the quality of the construction can be guaranteed, and the project construction meets the requirements of energy conservation and environmental protection. Therefore, it is necessary to analyze the development status of municipal bridge engineering construction and summarize the existing problems. The traditional technology and prefabricated technology are compared and analyzed to understand the construction advantages of prefabricated bridge, and the reasonable application strategies are put forward. Based on this, this paper discusses the application of prefabricated technology in municipal bridge engineering, in order to provide reference for relevant units.
文摘With the continuous development of highway and bridge projects in China, the scale and scope of construction are constantly expanding, and people have increasingly high requirements for the quality of highway and bridge projects. In order to meet peoples quality needs at this stage and ensure peoples travel safety, it is necessary to constantly strengthen the quality control of the project during the actual construction process, relevant staff should be able to deeply understand the types of accidents that are easy to occur in the construction process. At the same time, they should continue to deal with accidents through thinking about problems, learning from experience and strengthening management, so as to ensure the smooth construction of highway and bridge projects and promote the rapid development of Chinas highway and bridge industry. The article first analyzes the common accidents in the construction of highway bridge engineering, and then focuses on the treatment countermeasures of the common accidents in the construction of highway bridge engineering, which can be used as a reference for readers.
文摘Road bridge can provide convenient for people to travel, in its construction, related construction units to realize the important role of safety management, accurately grasp the construction key points, innovation and optimize safety management measures, strengthen safety management and quality control, to ensure the smooth construction of the project, maintenance personnel safety, make the project more durable, stable and safe. At the same time, in different regions, we should implement the basic principle of adjusting measures to local conditions and according to current conditions, save construction costs to a greater extent, focus on environmental protection, take more practical measures, so that the overall project can achieve better efficiency, and then provide necessary conditions for the embodiment of the comprehensive efficiency of the project.
文摘Engineering surveying is an important course for road and bridge engineering technology majors in higher vocational colleges.With the advancement of science and technology,engineering surveying technology is also constantly developing,so the theoretical knowledge and professional skills that students need to master are also becoming increasingly complicated.To stimulate the students’interest in learning the course,it is necessary to continuously introduce innovative teaching methods into the course.In this paper,the importance of teaching innovation in engineering surveying courses of road and bridge engineering technology majors in higher vocational colleges and the knowledge system that students need to master are analyzed.Subsequently,innovative strategies are proposed to help improve the students’mastery of engineering surveying.
基金supported by the National Natural Science Foundation of China(Grant Nos.52278304,52025082)the Science and Technology Innovation Program of Hunan Province(Grant No.2023RC3090)the Changsha Outstanding Innovative Youth Culturing Program(Grant No.kq2209009)。
文摘Bridges may suffer from large-amplitude vibrations due to strong winds,earthquakes,human-induced loads,and vehicle-induced dynamic loads.Metallic dampers employed the energy dissipation from the hysteretic behavior of metal materials are among the most effective methods to mitigate bridge vibrations.This paper reviews the development and application of metallic-yielding dampers for the vibration control of bridges.Various theoretical models for metallic damper analyses are reviewed.Different yielding mechanisms and manufacturing materials of metallic dampers are discussed.Finally,the recent progress and application of bridge engineering are summarized.It can be concluded that each section of the torsion-type metallic damper exhibits a uniform stress state and undergoes plastic deformation simultaneously.Therefore,the damper has a strong energy dissipation capacity.Additionally,self-centering metallic dampers can automatically recover to their initial position after suffering an earthquake.Combined metallic dampers can take advantage of different types of dampers,thereby enhancing damping performance.Finally,these dampers will significantly enhance the seismic performance and overall safety of bridge structures.Future research will likely focus on hybrid systems that combine metallic dampers with other energy consumption mechanisms to further improve adaptability and energy dissipation,advancing the resilience and safety of bridge structures.
文摘This article analyzes the application strategies of shotcrete anchor support technology using a highway bridge-tunnel construction project as an example.The article covers various strategies,including support plan formulation,mortar shotcrete anchor construction,grid steel frame construction,steel mesh construction,and concrete support construction.This analysis aims to provide a guideline for those interested in applying this technology and improving the quality and safety of highway bridges and tunnels construction.
基金supported by the National Key R&D Program of China(Grant No.2021YFC2100100)the General Program of National Natural Science Foundation of China(22178146)+1 种基金the Program for Young Talents in Chinathe Fundamental Research Funds for the Central Universities(JUSRP622011).
文摘D-p-hydroxyphenylglycine(D-HPG)is an important intermediate in the pharmaceutical industry,and it is commonly syn-thesized by cascading D-hydantoinase(DHase)and D-carbamoylase(DCase).In this study,the stability of DCase was identified as the main problem that limits its application.Therefore,the complexed structure of AkDCase(DCase from the Agrobacterium sp.strain KNK712)with the substrate N-carbamoyl-D-p-hydroxyphenylglycine(CpHPG)(with 2.52Åresolution)and catalytic mechanism were resolved.Based on the catalytic mechanism and electrostatic stabilization,salt bridge engineering was adopted to improve AkDCase thermostability.The best variant,AkDCase^(D30A),increased theTm by 2.91℃and half-life(t_(1/2))at 40 and 60℃by 18.43 h and 23.21 min,respectively.After AkDCase^(D30A) was assembled with GsDHase(DHase from Geobacillus stearothermophilus SD-1)in a single Escherichia coli cell,the recombinant strain could produce 29.53 g/L D-HPG within 12 h,with a 97%conversion and a 2.46 g/(L·h)space-time yield(STY).The titer of D-HPG increased by 40.55%compared to the E.coli cell harboring pETduet-1-AkDCase-GsDHase.The recombinant strain could be used for two cycles.Our research provides a basis for the industrial production of D-HPG.
基金National Natural Science Foundation of China under Grant Nos.51408359,52278527 and 52478536。
文摘To address local concrete damage in joint areas at the footing of prefabricated assembled self-centering bridge piers(PASPs)in seismic design,a damage transfer configuration(DTC)was proposed,based on the bridge pier structure configuration and the mechanism of local damage formation.Integrating the DTC into the PASP,numerical models of a previous experimental reference PASP and a PASP with damage transfer configuration(DTPASP)were established using the finite element software ABAQUS with a concrete damage plasticity(CDP)model.The models were then compared with experimental results regarding damage distribution,hysteresis curves,energy dissipation capacity,the joint opening degree,and residual displacement.The findings indicate that the finite element model developed in this study can well reflect the experimental results of the reference PASP.The incorporation of the DTC proved to be beneficial in preserving structural integrity,bearing capacity,and the functionality of the core structure of bridge piers following an earthquake.Meanwhile,this addition did not exert a significant influence on the seismic behavior of the core structure of the bridge pier.
文摘The theoretical design method of enhanced sensitivity fiber grating （FBG） strain sensors was given, and moreover high qualified strain sensors were developed and fabricated, whose sensing properties were good for practical applications. The strain sensor with cylindrical shell encapsulation contained three tubular structures, due to the uneven surface structure, in the area of the strain concentration, improving the sensitivity. It could achieve the embedment strain measurement and surface measurement and had the advantages of the easy installation. The good agreement was obtained between the measurements and theoretical simulation results. After each calibration test, twenty-four FBG strain sensors and six FBG temperature compensation sensors have been installed on the undersurface of the box girder of Diaoshuiyan bridge in Yongtaiwen highway. Finally, we built up a long-term structure health system for the highway bridge.
基金Project(2022YFC3004304)supported by the National Key Research and Development Program of ChinaProjects(52078487,U1934207,52178180)supported by the National Natural Science Foundation of China+2 种基金Project(2022TJ-Y10)supported by the Hunan Province Science and Technology Talent Lifting Project,ChinaProject(2023QYJC006)supported by the Frontier Cross Research Project of Central South University,ChinaProject(SKL-IoTSC(UM)-2024-2026/ORP/GA08/2023)supported by the Science and Technology Development Fund and the State Key Laboratory of Internet of Things for Smart City(University of Macao),China。
文摘In the realm of high-speed railway bridge engineering,managing the intricacies of the track-bridge system model(TBSM)during seismic events remains a formidable challenge.This study pioneers an innovative approach by presenting a simplified bridge model(SBM)optimized for both computational efficiency and precise representation,a seminal contribution to the engineering design landscape.Central to this innovation is a novel model-updating methodology that synergistically melds artificial neural networks with an augmented particle swarm optimization.The neural networks adeptly map update parameters to seismic responses,while enhancements to the particle swarm algorithm’s inertial and learning weights lead to superior SBM parameter updates.Verification via a 4-span high-speed railway bridge revealed that the optimized SBM and TBSM exhibit a highly consistent structural natural period and seismic response,with errors controlled within 7%.Additionally,the computational efficiency improved by over 100%.Leveraging the peak displacement and shear force residuals from the seismic TBSM and SBM as optimization objectives,SBM parameters are adeptly revised.Furthermore,the incorporation of elastoplastic springs at the beam ends of the simplified model effectively captures the additional mass,stiffness,and constraint effects exerted by the track system on the bridge structure.
