Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on ...Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine slides.Historical incidents have highlighted the substantial damage to pipelines due to slides.Specifically,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant threat.Accurately assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline safety.This study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact forces.These factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of pipelines.Additionally,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with pipelines.Building upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.展开更多
The responses of the pavement in service are the basis for the design of the semi-rigid base course asphalt pavement. Due to the dynamic characteristics of wheel loacis and the temperature loads, the dynamic response ...The responses of the pavement in service are the basis for the design of the semi-rigid base course asphalt pavement. Due to the dynamic characteristics of wheel loacis and the temperature loads, the dynamic response analysis is very significant. In this article, the dynamic analysis of asphalt pavement under moving wheel loads is carried out using finite dement method canpled with non-reflective boundary method. The influences of the base modulus, thickness, the vehicle velocity, the tire pressure, and the contact condition at the interface are studied using parametric analysis. The results of numerical analysis show that it is not appropriate to simply increase the base modulus or thickness in the design. It would be beneficial if the base design is optimized synthetically. The increase of damping is also beneficial to the pavements because of the surface deflection and the stresses declination. Furthermore, the good contact condition at the interface results in good performance because it combines every layer of the pavement to work together. As overload aggravates the working condition of the pavement, it is not allowed.展开更多
基金supported by the opening fund of State Key Laboratory of Coastal and Offshore Engineering at Dalian University of Technology(No.LP2310)the opening fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection at Chengdu University of Technology(No.SKLGP2023K001)+2 种基金the Shandong Provincial Key Laboratory of Ocean Engineering with grant at Ocean University of China(No.kloe200301)the National Natural Science Foundation of China(Nos.42022052,42077272 and 52108337)the Science and Technology Innovation Serve Project of Wenzhou Association for Science and Technology(No.KJFW65).
文摘Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine slides.Historical incidents have highlighted the substantial damage to pipelines due to slides.Specifically,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant threat.Accurately assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline safety.This study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact forces.These factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of pipelines.Additionally,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with pipelines.Building upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.
基金This paper is supported by the Programfor New Century Excellent Talents in University(2004)and Highway Depart ment of Henan Province
文摘The responses of the pavement in service are the basis for the design of the semi-rigid base course asphalt pavement. Due to the dynamic characteristics of wheel loacis and the temperature loads, the dynamic response analysis is very significant. In this article, the dynamic analysis of asphalt pavement under moving wheel loads is carried out using finite dement method canpled with non-reflective boundary method. The influences of the base modulus, thickness, the vehicle velocity, the tire pressure, and the contact condition at the interface are studied using parametric analysis. The results of numerical analysis show that it is not appropriate to simply increase the base modulus or thickness in the design. It would be beneficial if the base design is optimized synthetically. The increase of damping is also beneficial to the pavements because of the surface deflection and the stresses declination. Furthermore, the good contact condition at the interface results in good performance because it combines every layer of the pavement to work together. As overload aggravates the working condition of the pavement, it is not allowed.