According to the results of accelerated tests of acidification corrosion depth and compressive strength of concretes subjected to sulfuric acid environments,the acidification depth laws of concretes were predicted bas...According to the results of accelerated tests of acidification corrosion depth and compressive strength of concretes subjected to sulfuric acid environments,the acidification depth laws of concretes were predicted based on the grey system theory.Thus,the remaining compressive strength was calculated when the acidification depth reached the protection layer thickness of concrete structures,which indicates that the limit state of durability failure can be defined based on strength degradation,and the calculation process was illustrated by an example.The calculated results show that the remaining compressive strength values in the durability failure limit state for the concrete structures exposed to p H=2 and 3 sulfuric acid water environments and wet-dry cyclic sulfuric acid environment with p H=2 are 74%,72%,and 80% of initialstrength,respectively.The method provides references for the durability evaluation of concrete structure design under the acidic environments.展开更多
Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emp...Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is required.This study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling equipment.The study specifically investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency stick-slip.These events not only hinder the efficiency of drilling but also lead to exhaustion and harm to the system’s components since they are difficult to be detected and controlled in real time.The study investigates the dynamic interactions of these vibrations,specifically in their high-frequency modes,usingfield data obtained from measurement while drilling.Thefindings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem performance.The obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control systems.Therefore,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect damage.Moreover,by exploiting thesefindings,the assessment of structural resilience in rotary drilling systems can be enhanced.Furthermore,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efficiency of rotary drilling systems in the petroleum industry.展开更多
To address the vibration issues of wind turbine towers,this paper proposes a bidirectional tuned bellow liquid column damper(BTBLCD).The configuration of the proposed BTBLCD is first described in detail,and its energy...To address the vibration issues of wind turbine towers,this paper proposes a bidirectional tuned bellow liquid column damper(BTBLCD).The configuration of the proposed BTBLCD is first described in detail,and its energy dissipation mechanism is derived through theoretical analysis.A refined dynamic model of the wind turbine tower equipped with the BTBLCD is then developed.The vibration energy dissipation performance of the BTBLCD in multiple directions is evaluated through two-way fluid-structure coupling numerical simulations.Finally,a 1/10 scaled model of the wind turbine tower is constructed,and the energy dissipation performance of the BTBLCD is validated using a shaking table test.The results show that the vibration energy dissipation performance of the BTBLCD outperforms that of the bidirectional tuned liquid column damper(BTLCD)in multiple directions.The shaking table test and dynamic response analysis demonstrate a maximum reduction of 61.0%in acceleration and 47.9%in displacement response.Furthermore,the vibration control and energy dissipation performance of the BTBLCD are influenced by the direction and amplitude of vibrations.This study contributes to the development of more effective and versatile vibration mitigation strategies for wind turbine tower structures in various engineering scenarios.展开更多
The construction industry faces significant challenges due to the inherent brittleness and cracking tendency of traditional concrete,which compromises structural durability and necessitates frequent,costly repairs.Thi...The construction industry faces significant challenges due to the inherent brittleness and cracking tendency of traditional concrete,which compromises structural durability and necessitates frequent,costly repairs.This paper explores the groundbreaking development of self-healing concrete as a transformative material technology for sustainable architecture.We examine three primary autogenous healing mechanisms:encapsulated polymer/microbial healing agents,vascular networks,and shape memory alloys.Through a review of recent laboratory experiments and pilot projects,this study analyzes the crack-sealing efficiency,recovery of mechanical properties,and long-term durability of these materials.A comparative case study of a demonstration building facade incorporating microbial self-healing concrete is presented,showing a potential 30%reduction in maintenance costs over a 20-year lifecycle.The findings indicate that self-healing concrete not only enhances structural resilience but also significantly reduces the carbon footprint associated with building maintenance,aligning with the core principles of sustainable development.The paper concludes by discussing current limitations in mass production and cost-effectiveness and proposes directions for future research to facilitate widespread adoption in architectural engineering.展开更多
Up to present, there have been no studies concerning the application of fluid-structure interaction（FSI） analysis to the lifetime estimation of multi-stage centrifugal compressors under dangerous unsteady aerodynami...Up to present, there have been no studies concerning the application of fluid-structure interaction（FSI） analysis to the lifetime estimation of multi-stage centrifugal compressors under dangerous unsteady aerodynamic excitations. In this paper, computational fluid dynamics（CFD） simulations of a three-stage natural gas pipeline centrifugal compressor are performed under near-choke and near-surge conditions, and the unsteady aerodynamic pressure acting on impeller blades are obtained. Then computational structural dynamics（CSD） analysis is conducted through a one-way coupling FSI model to predict alternating stresses in impeller blades. Finally, the compressor lifetime is estimated using the nominal stress approach. The FSI results show that the impellers of latter stages suffer larger fluctuation stresses but smaller mean stresses than those at preceding stages under near-choke and near-surge conditions. The most dangerous position in the compressor is found to be located near the leading edge of the last-stage impeller blade. Compressor lifetime estimation shows that the investigated compressor can run up to 102.7 h under the near-choke condition and 200.2 h under the near-surge condition. This study is expected to provide a scientific guidance for the operation safety of natural gas pipeline centrifugal compressors.展开更多
The main purpose of this paper is providing a reference for further research. According to the papers and reports on structural durability and probabilistic damage tolerance, the present paper summarized the pro- gres...The main purpose of this paper is providing a reference for further research. According to the papers and reports on structural durability and probabilistic damage tolerance, the present paper summarized the pro- gress of the theoretical considerations and engineering application. Several models used in structural durability and probabilistic damage tolerance are reviewed. The characteristics and problems of these methods are ana- lyzed. A new kind of combined analysis model on structural durability and damage tolerance are also introduced. New progress of analysis theory and numerical methods on structural reliability are discussed, such as the re- sponse surface method and numerical method combining neural networks and Monte Carlo simulation. The analy- sis shows that these methods can improve computational efficiency significantly and maintain high computational accuracy. Finally, some prospects of the key research directions are discussed.展开更多
The total storage of full containment LNG storage tanks is very huge. Once the tank rupture or leakage, the consequence will be unimaginable. Therefore it is necessary to perform the risk-based inspection （RBI） and ...The total storage of full containment LNG storage tanks is very huge. Once the tank rupture or leakage, the consequence will be unimaginable. Therefore it is necessary to perform the risk-based inspection （RBI） and evaluation on LNG storage tanks, and the analysis on LNG storage tanks failure possibility is especially important in the RBI. Recently, Risk-based inspection （RBI） technology based on API 581 is gradually adopted and has become a new technology to determine economic feasibility and safety of equipment in petrochemical plants. However, there are limitations of applying API 581 to LNG equipment because of the unique structure of LNG storage tank （the metal inner tank and concrete outer tank）. Therefore, a failure probability calculation model suitable for full containment LNG storage tanks is proposed. The domestic inner tank is usually made of 9%Ni, and its failure possibility can be calculate based on API581; the outer tank is usually made of pre-stressed concrete, and the failure possibility of structure durability can be calculated by the method of fuzzy mathematics ; Then the failure possibility of the inner tank and the outer tank will be comprehensive considered by using cellulose model. Finally, by citing a real example, it also detailedly introduces the application of this proposed calculation model in the failure possibility analysis of full containment LNG storage tanks. This study provides a new approach for the evaluation of failure possibility on full containment LNG storage tanks.展开更多
Concrete structure is commonly used in the anchorages of a large cable-suspended pipeline crossing construction.With the increase of span and load,the stress on the concrete anchorages may rise rapidly.In case of trad...Concrete structure is commonly used in the anchorages of a large cable-suspended pipeline crossing construction.With the increase of span and load,the stress on the concrete anchorages may rise rapidly.In case of traditional anchoring structurefixed by anchor rods,concrete cracking will occur,thereby reducing the anchorage life.To solve this problem,the pre-stressed structure was designed to effectively improve the ef-ficiency of anchoring and reduce engineering cost.In the crossing construction of ChinaeMyanmar Gas Pipeline,the pre-stressed technology was used to establish an effective pre-stressed anchoring system,which integrates the pre-stressed structures(e.g.tunnel anchorages in the anchors)and the optimization measures(e.g.positioning mode,anchorage structure,concrete placement,pre-stressed,and medium injection),in line with the crossing structure and load features of this project.The system can delay the occurrence of concrete cracking and enhance the stress durability of the structure and anchoring efficiency.This technology has been successfully applied in the crossing construction of Chi-naeMyanmar Gas Pipeline,with good economic and social benefits,indicating that this technology is a new effective solution to the opti-mization of suspended pipeline anchorage structures,providing technical support for the development of pipeline crossing structure.展开更多
Construction failures caused by unforeseen circumstances, such as natural disasters, environmental degradation, and structural weaknesses, present significant challenges in achieving durability, safety, and sustainabi...Construction failures caused by unforeseen circumstances, such as natural disasters, environmental degradation, and structural weaknesses, present significant challenges in achieving durability, safety, and sustainability. This research addresses these challenges through the development of advanced emergency rescue systems incorporating wood-derived nanomaterials and IoT-enabled Structural Health Monitoring (SHM) technologies. The use of nanocellulose which demonstrates outstanding mechanical capabilities and biodegradability alongside high resilience allowed developers to design modular rescue systems that function effectively even under challenging conditions while providing real-time failure protection. Experimental data from testing showed that the replacement system strengthened load-bearing limits by 20% while enhancing impact tolerance by 30% and decreasing lifecycle carbon footprints by 60% against conventional methods. FEA results alongside dynamic simulations established that the system maintains its strength across seismic events and thermal variations and environmental conditions. SHM systems that leverage the Internet of Things Platform revealed 95% accuracy rates in detecting anomalies while improving response speed by 30% for predictive maintenance operations. The innovative solutions support the special issue’s direction to push structural transformation through durable designs and creative materials with preventive failure solutions. The proposed solutions work together toward creating resilient infrastructure systems which resist unexpected stressors and environmental damage.展开更多
The concept of sustainability is described in this paper using a single sustainable principle,two goals of sustainable development,three dimensions of sustainable engineering,four sustainable requirements and five pha...The concept of sustainability is described in this paper using a single sustainable principle,two goals of sustainable development,three dimensions of sustainable engineering,four sustainable requirements and five phases of sustainable construction.Four sustainable requirements and their practice in China are discussed in particular.The safe reliability of bridges is first compared with the events of bridge failure in China and in the rest of the world and followed by structural durability,including the cracking of concrete cable-stayed bridges,deflection of concrete girder bridges and fatigue cracks of orthotropic steel decks.With respect to functional adaptability,lateral wind action on vehicles and its improvement are introduced regarding a sea-crossing bridge located in a typhoon-prone area.The Chinese practice of using two double main span suspension bridges and a twin parallel deck cable-stayed bridge is presented in discussing the final sustainable requirement:capacity extensibility.展开更多
基金Funded by the Nnational Natural Science Foundation of China(51372185)
文摘According to the results of accelerated tests of acidification corrosion depth and compressive strength of concretes subjected to sulfuric acid environments,the acidification depth laws of concretes were predicted based on the grey system theory.Thus,the remaining compressive strength was calculated when the acidification depth reached the protection layer thickness of concrete structures,which indicates that the limit state of durability failure can be defined based on strength degradation,and the calculation process was illustrated by an example.The calculated results show that the remaining compressive strength values in the durability failure limit state for the concrete structures exposed to p H=2 and 3 sulfuric acid water environments and wet-dry cyclic sulfuric acid environment with p H=2 are 74%,72%,and 80% of initialstrength,respectively.The method provides references for the durability evaluation of concrete structure design under the acidic environments.
文摘Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is required.This study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling equipment.The study specifically investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency stick-slip.These events not only hinder the efficiency of drilling but also lead to exhaustion and harm to the system’s components since they are difficult to be detected and controlled in real time.The study investigates the dynamic interactions of these vibrations,specifically in their high-frequency modes,usingfield data obtained from measurement while drilling.Thefindings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem performance.The obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control systems.Therefore,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect damage.Moreover,by exploiting thesefindings,the assessment of structural resilience in rotary drilling systems can be enhanced.Furthermore,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efficiency of rotary drilling systems in the petroleum industry.
基金support for the research,authorship,and/or publication of this paper:This study is supported by the National Science Foundation of China(Grant No.52368074)the Science Fund for Distinguished Young Scholars of Gansu Province(No.21JR7RA267)Hongliu Outstanding Young Talents Program of Lanzhou University of Technology.
文摘To address the vibration issues of wind turbine towers,this paper proposes a bidirectional tuned bellow liquid column damper(BTBLCD).The configuration of the proposed BTBLCD is first described in detail,and its energy dissipation mechanism is derived through theoretical analysis.A refined dynamic model of the wind turbine tower equipped with the BTBLCD is then developed.The vibration energy dissipation performance of the BTBLCD in multiple directions is evaluated through two-way fluid-structure coupling numerical simulations.Finally,a 1/10 scaled model of the wind turbine tower is constructed,and the energy dissipation performance of the BTBLCD is validated using a shaking table test.The results show that the vibration energy dissipation performance of the BTBLCD outperforms that of the bidirectional tuned liquid column damper(BTLCD)in multiple directions.The shaking table test and dynamic response analysis demonstrate a maximum reduction of 61.0%in acceleration and 47.9%in displacement response.Furthermore,the vibration control and energy dissipation performance of the BTBLCD are influenced by the direction and amplitude of vibrations.This study contributes to the development of more effective and versatile vibration mitigation strategies for wind turbine tower structures in various engineering scenarios.
文摘The construction industry faces significant challenges due to the inherent brittleness and cracking tendency of traditional concrete,which compromises structural durability and necessitates frequent,costly repairs.This paper explores the groundbreaking development of self-healing concrete as a transformative material technology for sustainable architecture.We examine three primary autogenous healing mechanisms:encapsulated polymer/microbial healing agents,vascular networks,and shape memory alloys.Through a review of recent laboratory experiments and pilot projects,this study analyzes the crack-sealing efficiency,recovery of mechanical properties,and long-term durability of these materials.A comparative case study of a demonstration building facade incorporating microbial self-healing concrete is presented,showing a potential 30%reduction in maintenance costs over a 20-year lifecycle.The findings indicate that self-healing concrete not only enhances structural resilience but also significantly reduces the carbon footprint associated with building maintenance,aligning with the core principles of sustainable development.The paper concludes by discussing current limitations in mass production and cost-effectiveness and proposes directions for future research to facilitate widespread adoption in architectural engineering.
基金Supported by National Natural Science Foundation of China(Grant No51406148)National Science Technology Support Program of China(Grant No.2012BAA08B06)Postdoctoral Science Foundation o China(Grant No.2014M552444)
文摘Up to present, there have been no studies concerning the application of fluid-structure interaction（FSI） analysis to the lifetime estimation of multi-stage centrifugal compressors under dangerous unsteady aerodynamic excitations. In this paper, computational fluid dynamics（CFD） simulations of a three-stage natural gas pipeline centrifugal compressor are performed under near-choke and near-surge conditions, and the unsteady aerodynamic pressure acting on impeller blades are obtained. Then computational structural dynamics（CSD） analysis is conducted through a one-way coupling FSI model to predict alternating stresses in impeller blades. Finally, the compressor lifetime is estimated using the nominal stress approach. The FSI results show that the impellers of latter stages suffer larger fluctuation stresses but smaller mean stresses than those at preceding stages under near-choke and near-surge conditions. The most dangerous position in the compressor is found to be located near the leading edge of the last-stage impeller blade. Compressor lifetime estimation shows that the investigated compressor can run up to 102.7 h under the near-choke condition and 200.2 h under the near-surge condition. This study is expected to provide a scientific guidance for the operation safety of natural gas pipeline centrifugal compressors.
文摘The main purpose of this paper is providing a reference for further research. According to the papers and reports on structural durability and probabilistic damage tolerance, the present paper summarized the pro- gress of the theoretical considerations and engineering application. Several models used in structural durability and probabilistic damage tolerance are reviewed. The characteristics and problems of these methods are ana- lyzed. A new kind of combined analysis model on structural durability and damage tolerance are also introduced. New progress of analysis theory and numerical methods on structural reliability are discussed, such as the re- sponse surface method and numerical method combining neural networks and Monte Carlo simulation. The analy- sis shows that these methods can improve computational efficiency significantly and maintain high computational accuracy. Finally, some prospects of the key research directions are discussed.
文摘The total storage of full containment LNG storage tanks is very huge. Once the tank rupture or leakage, the consequence will be unimaginable. Therefore it is necessary to perform the risk-based inspection （RBI） and evaluation on LNG storage tanks, and the analysis on LNG storage tanks failure possibility is especially important in the RBI. Recently, Risk-based inspection （RBI） technology based on API 581 is gradually adopted and has become a new technology to determine economic feasibility and safety of equipment in petrochemical plants. However, there are limitations of applying API 581 to LNG equipment because of the unique structure of LNG storage tank （the metal inner tank and concrete outer tank）. Therefore, a failure probability calculation model suitable for full containment LNG storage tanks is proposed. The domestic inner tank is usually made of 9%Ni, and its failure possibility can be calculate based on API581; the outer tank is usually made of pre-stressed concrete, and the failure possibility of structure durability can be calculated by the method of fuzzy mathematics ; Then the failure possibility of the inner tank and the outer tank will be comprehensive considered by using cellulose model. Finally, by citing a real example, it also detailedly introduces the application of this proposed calculation model in the failure possibility analysis of full containment LNG storage tanks. This study provides a new approach for the evaluation of failure possibility on full containment LNG storage tanks.
基金2011-2012 S&T project of CNPC Chuanqing Drilling Engineering Co.,“Study on Applicability of crossing construction technology in Chinae-Myanmar pipeline project”。
文摘Concrete structure is commonly used in the anchorages of a large cable-suspended pipeline crossing construction.With the increase of span and load,the stress on the concrete anchorages may rise rapidly.In case of traditional anchoring structurefixed by anchor rods,concrete cracking will occur,thereby reducing the anchorage life.To solve this problem,the pre-stressed structure was designed to effectively improve the ef-ficiency of anchoring and reduce engineering cost.In the crossing construction of ChinaeMyanmar Gas Pipeline,the pre-stressed technology was used to establish an effective pre-stressed anchoring system,which integrates the pre-stressed structures(e.g.tunnel anchorages in the anchors)and the optimization measures(e.g.positioning mode,anchorage structure,concrete placement,pre-stressed,and medium injection),in line with the crossing structure and load features of this project.The system can delay the occurrence of concrete cracking and enhance the stress durability of the structure and anchoring efficiency.This technology has been successfully applied in the crossing construction of Chi-naeMyanmar Gas Pipeline,with good economic and social benefits,indicating that this technology is a new effective solution to the opti-mization of suspended pipeline anchorage structures,providing technical support for the development of pipeline crossing structure.
文摘Construction failures caused by unforeseen circumstances, such as natural disasters, environmental degradation, and structural weaknesses, present significant challenges in achieving durability, safety, and sustainability. This research addresses these challenges through the development of advanced emergency rescue systems incorporating wood-derived nanomaterials and IoT-enabled Structural Health Monitoring (SHM) technologies. The use of nanocellulose which demonstrates outstanding mechanical capabilities and biodegradability alongside high resilience allowed developers to design modular rescue systems that function effectively even under challenging conditions while providing real-time failure protection. Experimental data from testing showed that the replacement system strengthened load-bearing limits by 20% while enhancing impact tolerance by 30% and decreasing lifecycle carbon footprints by 60% against conventional methods. FEA results alongside dynamic simulations established that the system maintains its strength across seismic events and thermal variations and environmental conditions. SHM systems that leverage the Internet of Things Platform revealed 95% accuracy rates in detecting anomalies while improving response speed by 30% for predictive maintenance operations. The innovative solutions support the special issue’s direction to push structural transformation through durable designs and creative materials with preventive failure solutions. The proposed solutions work together toward creating resilient infrastructure systems which resist unexpected stressors and environmental damage.
基金The work described in this paper is partially supported by the Natural Science Foundation of China(Grant Nos.90715039 and 51021140005)by the Ministry of Science and Technology of China(Grant Nos.2006AA11Z108 and 2008BAG07B02).
文摘The concept of sustainability is described in this paper using a single sustainable principle,two goals of sustainable development,three dimensions of sustainable engineering,four sustainable requirements and five phases of sustainable construction.Four sustainable requirements and their practice in China are discussed in particular.The safe reliability of bridges is first compared with the events of bridge failure in China and in the rest of the world and followed by structural durability,including the cracking of concrete cable-stayed bridges,deflection of concrete girder bridges and fatigue cracks of orthotropic steel decks.With respect to functional adaptability,lateral wind action on vehicles and its improvement are introduced regarding a sea-crossing bridge located in a typhoon-prone area.The Chinese practice of using two double main span suspension bridges and a twin parallel deck cable-stayed bridge is presented in discussing the final sustainable requirement:capacity extensibility.
