The theoretical formulations of Coulomb and Rankine still remain as the fundamental approaches to the analysis of most gravity-type retaining wall,with the assumption that sufficient lateral yield will occur to mobili...The theoretical formulations of Coulomb and Rankine still remain as the fundamental approaches to the analysis of most gravity-type retaining wall,with the assumption that sufficient lateral yield will occur to mobilize fully limited conditions behind the wall.The effects of the magnitude of wall movements and different wall-movement modes are not taken into consideration.The disturbance of backfill is considered to be related to the wall movement under translation mode.On the basis of disturbed state concept(DSC),a general disturbance function was proposed which ranged from-1 to 1.The disturbance variables could be determined from the measured wall movements.A novel approach that related to disturbed degree and the mobilized internal frictional angle of the backfill was also derived.A calculation method benefited from Rankine's theory and the proposed approach was established to predict the magnitude and distribution of earth pressure from the cohesionless backfill under translation mode.The predicted results,including the magnitude and distribution of earth pressure,show good agreement with those of the model test and the finite element method.In addition,the disturbance parameter b was also discussed.展开更多
Mesoscopic characteristics of a clayey soil specimen subjected to macroscopic loading are examined using a medi- cal-use computerized tomography (CT) instrument. Disturbed state concept (DSC) theory is based on the ut...Mesoscopic characteristics of a clayey soil specimen subjected to macroscopic loading are examined using a medi- cal-use computerized tomography (CT) instrument. Disturbed state concept (DSC) theory is based on the utilization of the hard- ening model. DSC indirectly describes material behavior by claiming that the actual response of the material is expressed in terms of the relative intact (RI) response and the fully adjusted (FA) response. The occurrence of mesoscopic structural changes of material has similarities with the occurrence of a macroscopic response of the material under loadings. In general, the relative changing value of a softening material is three to five times more than that of a hardening material. Whether special zones exist or not in a specimen cross section does not affect the following conclusion: hardening material and softening material show me- chanical differences with CT statistical indices values prominently changing, and the change is related to the superposing of a disturbance factor. A new disturbance factor evolution function is proposed. Thus, mesoscopic statistical indices are introduced to describe macroscopic behavior through the new evolution function. An application of the new evolution function proves the effectiveness of the amalgamation of a macroscopic and a mesoscopic experimental phenomenon measurement methods.展开更多
A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeforma...A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeformations, stress path, volume change, microcracking leading to fracture, failure and softening,stiffening, and mechanical and environmental forces. There are hardly available such unified models. Thedisturbed state concept （DSC） is considered to be a unified approach and is able to provide materialcharacterization for almost all of the above factors. This paper presents a description of the DSC, andstatements for determination of parameters based on triaxial, multiaxial and interface tests. Statementsof DSC and validation at the specimen level and at the boundary value problem levels are also presented.An extensive list of publications by the author and others is provided at the end. The DSC is considered tobe a unique and versatile procedure for modeling behaviors of engineering materials and interfaces. 2016 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. This is an open access article under the CC BY-NC-ND license展开更多
Based on the following two points that one is the social disorder resulted from the“republic”since the Revolution of 1911 and the other is constant reflection on the recognition of the political values of western po...Based on the following two points that one is the social disorder resulted from the“republic”since the Revolution of 1911 and the other is constant reflection on the recognition of the political values of western political parties,Li Dazhao places his hope on awakening and strength of the people to deal with the gap between republican political ideal and social reality of the Republic of China finally.This kind of emphasis and expectation on the power of people makes up a key factor assisting Li Dazhao’s early conversion to Marxism.展开更多
基于扰动状态概念(Disturbed State Concept,DSC),结合Rayleigh分布从微观角度描述桩-土界面荷载渐进性传递特性,建立了基于DSC理论的桩侧及桩端荷载传递模型,给出了模型参数确定方法,并验证了模型的合理性.同时结合桩侧及桩端荷载传递...基于扰动状态概念(Disturbed State Concept,DSC),结合Rayleigh分布从微观角度描述桩-土界面荷载渐进性传递特性,建立了基于DSC理论的桩侧及桩端荷载传递模型,给出了模型参数确定方法,并验证了模型的合理性.同时结合桩侧及桩端荷载传递模型,提出了一种分析单桩承载特性的迭代算法并验证其合理性.通过算法计算得到的单桩承载特性与案例实测值有较好的一致性,且可较好地反映侧阻及端阻硬化、软化等特性.变参数分析结果表明,基于DSC理论的桩侧及桩端荷载传递模型对不同土层、不同桩基施工工艺都有好的适用性,可较准确地描述桩-土界面荷载传递特性.展开更多
在中国经济转向创新驱动的背景下,科技成果转移转化工作为促进科技向生产力和经济发展转变发挥了关键作用。聚焦科技成果转移转化过程的“最初一公里”——概念验证(proof of concept,POC)及概念验证中心(proof of concept center,POCC...在中国经济转向创新驱动的背景下,科技成果转移转化工作为促进科技向生产力和经济发展转变发挥了关键作用。聚焦科技成果转移转化过程的“最初一公里”——概念验证(proof of concept,POC)及概念验证中心(proof of concept center,POCC)建设,通过详细回顾美国在这一领域的发展历程,特别是德什潘德中心和佐治亚理工创业实验室(VentureLab)的案例研究,揭示了POCC在支持早期科技创新和促进商业化方面成功经验及重要作用。美国POCC的运作模式和成功要素为理解如何帮助创业团队评估商业可行性提供了有价值的参考;基于对美国经验的分析,提出了一系列针对中国在POCC建设方面的策略和建议,包括发挥政府引导作用、融合多元主体和强化创新体系、发挥中国特色。这些建议旨在促进科技成果的商业化,加强大学、政府和企业之间的协同创新,从而推动科技创新不断面向国民经济主战场。展开更多
基金Project(50678158) supported by the National Natural Science Foundation of China
文摘The theoretical formulations of Coulomb and Rankine still remain as the fundamental approaches to the analysis of most gravity-type retaining wall,with the assumption that sufficient lateral yield will occur to mobilize fully limited conditions behind the wall.The effects of the magnitude of wall movements and different wall-movement modes are not taken into consideration.The disturbance of backfill is considered to be related to the wall movement under translation mode.On the basis of disturbed state concept(DSC),a general disturbance function was proposed which ranged from-1 to 1.The disturbance variables could be determined from the measured wall movements.A novel approach that related to disturbed degree and the mobilized internal frictional angle of the backfill was also derived.A calculation method benefited from Rankine's theory and the proposed approach was established to predict the magnitude and distribution of earth pressure from the cohesionless backfill under translation mode.The predicted results,including the magnitude and distribution of earth pressure,show good agreement with those of the model test and the finite element method.In addition,the disturbance parameter b was also discussed.
文摘Mesoscopic characteristics of a clayey soil specimen subjected to macroscopic loading are examined using a medi- cal-use computerized tomography (CT) instrument. Disturbed state concept (DSC) theory is based on the utilization of the hard- ening model. DSC indirectly describes material behavior by claiming that the actual response of the material is expressed in terms of the relative intact (RI) response and the fully adjusted (FA) response. The occurrence of mesoscopic structural changes of material has similarities with the occurrence of a macroscopic response of the material under loadings. In general, the relative changing value of a softening material is three to five times more than that of a hardening material. Whether special zones exist or not in a specimen cross section does not affect the following conclusion: hardening material and softening material show me- chanical differences with CT statistical indices values prominently changing, and the change is related to the superposing of a disturbance factor. A new disturbance factor evolution function is proposed. Thus, mesoscopic statistical indices are introduced to describe macroscopic behavior through the new evolution function. An application of the new evolution function proves the effectiveness of the amalgamation of a macroscopic and a mesoscopic experimental phenomenon measurement methods.
文摘A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeformations, stress path, volume change, microcracking leading to fracture, failure and softening,stiffening, and mechanical and environmental forces. There are hardly available such unified models. Thedisturbed state concept （DSC） is considered to be a unified approach and is able to provide materialcharacterization for almost all of the above factors. This paper presents a description of the DSC, andstatements for determination of parameters based on triaxial, multiaxial and interface tests. Statementsof DSC and validation at the specimen level and at the boundary value problem levels are also presented.An extensive list of publications by the author and others is provided at the end. The DSC is considered tobe a unique and versatile procedure for modeling behaviors of engineering materials and interfaces. 2016 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. This is an open access article under the CC BY-NC-ND license
基金supported by Research Project on Major Theoretical and Practical Issues of Philosophy and Social Sciences in Shanxi Province named on“Research on the Early CPC’s Cognition of People’s Times and the Generation of Great Party Building Spirit”(2022ND0393)supported by the Fundamental Research Funds for the Central Universities named on“Research on the Early Historical Formation of the Great Party Building Spirit”(XJS222110).
文摘Based on the following two points that one is the social disorder resulted from the“republic”since the Revolution of 1911 and the other is constant reflection on the recognition of the political values of western political parties,Li Dazhao places his hope on awakening and strength of the people to deal with the gap between republican political ideal and social reality of the Republic of China finally.This kind of emphasis and expectation on the power of people makes up a key factor assisting Li Dazhao’s early conversion to Marxism.
文摘基于扰动状态概念(Disturbed State Concept,DSC),结合Rayleigh分布从微观角度描述桩-土界面荷载渐进性传递特性,建立了基于DSC理论的桩侧及桩端荷载传递模型,给出了模型参数确定方法,并验证了模型的合理性.同时结合桩侧及桩端荷载传递模型,提出了一种分析单桩承载特性的迭代算法并验证其合理性.通过算法计算得到的单桩承载特性与案例实测值有较好的一致性,且可较好地反映侧阻及端阻硬化、软化等特性.变参数分析结果表明,基于DSC理论的桩侧及桩端荷载传递模型对不同土层、不同桩基施工工艺都有好的适用性,可较准确地描述桩-土界面荷载传递特性.
文摘在中国经济转向创新驱动的背景下,科技成果转移转化工作为促进科技向生产力和经济发展转变发挥了关键作用。聚焦科技成果转移转化过程的“最初一公里”——概念验证(proof of concept,POC)及概念验证中心(proof of concept center,POCC)建设,通过详细回顾美国在这一领域的发展历程,特别是德什潘德中心和佐治亚理工创业实验室(VentureLab)的案例研究,揭示了POCC在支持早期科技创新和促进商业化方面成功经验及重要作用。美国POCC的运作模式和成功要素为理解如何帮助创业团队评估商业可行性提供了有价值的参考;基于对美国经验的分析,提出了一系列针对中国在POCC建设方面的策略和建议,包括发挥政府引导作用、融合多元主体和强化创新体系、发挥中国特色。这些建议旨在促进科技成果的商业化,加强大学、政府和企业之间的协同创新,从而推动科技创新不断面向国民经济主战场。
