According to our analysis of variations in Chinas＇ industrial growth rate. industrial demand, industrial structure, regional structure and the performance of industrial firms, China ＇s＇ industrial economv is moving...According to our analysis of variations in Chinas＇ industrial growth rate. industrial demand, industrial structure, regional structure and the performance of industrial firms, China ＇s＇ industrial economv is moving towards＇ a ＂new normal＂ of slower growth and structural improvement. This process coincides with the late stage of China＇s industrialization, which international experience suggests is often frauht with twists and challenges. Among these challenges, great attention must be paid to overcapacity industrial restructuring and upgrades, and the ＂reindustrialization＂ of developed countries. As China enters the late stage of its industrialization, particularly during the 13th Five-Year Plan period from 2016 to 2020, the promotion of industrial development is of strategic significance for China to successfully complete industrialization and its economy to adapt to the ＂new normal ＂. In the face of these new challenges regarding industrial development, policymakers must strive to increase the dynamism of growth for industrial economy. In this new era, the momentum of industrial growth derives from the integration of the supply impetus of industrialization and the pull of demand caused by urbanization, while, the comprehensive deepening of refom provides the key source of momentum.展开更多
The Fenghua River Bridge is a major structure on the highway between Hengzhang and Guojiachi, which is to be built with a four-span prestress concrete (PC) box girder and symmetrical cantilever castings. In this paper...The Fenghua River Bridge is a major structure on the highway between Hengzhang and Guojiachi, which is to be built with a four-span prestress concrete (PC) box girder and symmetrical cantilever castings. In this paper, a finite element method (FEM) model is set up to study the effects of concrete differential aging time on the construction phases of the Fenghua River Bridge by calculating the vertical displacement of the folding segment of the middle span and the longitudinal bending moment of Pier 12#. In the model, the girders are classified into 150 changing sections based on the desgn scheme, and their construction is to be carried in 16 phases respectively to build 12 blocks connected by a side folding segment and a middle folding segment, covered with a second dead load and in completion for 20 years. It is found that the internal forces and deformations of the concrete structures at the aging time of 60 d are quite different from those of 0 d aging time while the behaviors of the structures of 120 d aging time is nearly the same as those of 60 d aging time― the differences are so small that can be neglected, suggesting that the creep develops obviously about one month after the cement is hardened and the development fades later on.展开更多
In order to investigate the behavior of buildings and engineering structures during earthquakes, based on the data of seismic observation devices mounted on constructions with typical characteristics, results of inves...In order to investigate the behavior of buildings and engineering structures during earthquakes, based on the data of seismic observation devices mounted on constructions with typical characteristics, results of investigating the change of mechanical properties of building structural system over time and the results of examination of structural rigidity and safety change over time, depending on the dynamic characteristics of the building, determined by experimental investigations made at intervals are mentioned in this article. In addition, evaluation of earthquake acceleration acting on structures due to earthquake-induced damage characteristics of buildings and engineering constructions which are made earthquake resistant is also included here.展开更多
Construction of mass concrete structures face more challenges in temperature difference and complex stress under low temperature than the ambient temperature. It has been proved by the practice that, not only improvin...Construction of mass concrete structures face more challenges in temperature difference and complex stress under low temperature than the ambient temperature. It has been proved by the practice that, not only improving tensile strength of structural concrete as soon as possible and removing of constrain as much as possible, but also calculation of the thermal stress in the process of construction and maintenance, controlling structure of concrete tensile strength and temperature difference stress ratio can ensure the safety and defect-free.展开更多
This article uses the age-structure/life-cycle method to analyze the impact of migrant workers’ employment on their urbanization. Since enterprises tend to employ younger workers and unemployed migrant workers tend t...This article uses the age-structure/life-cycle method to analyze the impact of migrant workers’ employment on their urbanization. Since enterprises tend to employ younger workers and unemployed migrant workers tend to be middle-aged, we first apply the age structure/life cycle model to carry out our estimations, pointing out that in order to complete the urbanization of their families, migrant worker couples usually have to work for thirty years consecutively after marriage. On this basis, the article constructs a working life table for migrant workers and uses it to estimate the total quantity of Chinese migrant workers who have the minimum economic capacity required for urbanization. Taking into consideration future changes in the age structure of enterprise employment, we estimate that over the sixty-nine million migrant workers who were under thirty years old in 2006, together with their families, would already be in possession of the minimum economic conditions for settling in urban areas.展开更多
文摘According to our analysis of variations in Chinas＇ industrial growth rate. industrial demand, industrial structure, regional structure and the performance of industrial firms, China ＇s＇ industrial economv is moving towards＇ a ＂new normal＂ of slower growth and structural improvement. This process coincides with the late stage of China＇s industrialization, which international experience suggests is often frauht with twists and challenges. Among these challenges, great attention must be paid to overcapacity industrial restructuring and upgrades, and the ＂reindustrialization＂ of developed countries. As China enters the late stage of its industrialization, particularly during the 13th Five-Year Plan period from 2016 to 2020, the promotion of industrial development is of strategic significance for China to successfully complete industrialization and its economy to adapt to the ＂new normal ＂. In the face of these new challenges regarding industrial development, policymakers must strive to increase the dynamism of growth for industrial economy. In this new era, the momentum of industrial growth derives from the integration of the supply impetus of industrialization and the pull of demand caused by urbanization, while, the comprehensive deepening of refom provides the key source of momentum.
文摘The Fenghua River Bridge is a major structure on the highway between Hengzhang and Guojiachi, which is to be built with a four-span prestress concrete (PC) box girder and symmetrical cantilever castings. In this paper, a finite element method (FEM) model is set up to study the effects of concrete differential aging time on the construction phases of the Fenghua River Bridge by calculating the vertical displacement of the folding segment of the middle span and the longitudinal bending moment of Pier 12#. In the model, the girders are classified into 150 changing sections based on the desgn scheme, and their construction is to be carried in 16 phases respectively to build 12 blocks connected by a side folding segment and a middle folding segment, covered with a second dead load and in completion for 20 years. It is found that the internal forces and deformations of the concrete structures at the aging time of 60 d are quite different from those of 0 d aging time while the behaviors of the structures of 120 d aging time is nearly the same as those of 60 d aging time― the differences are so small that can be neglected, suggesting that the creep develops obviously about one month after the cement is hardened and the development fades later on.
文摘In order to investigate the behavior of buildings and engineering structures during earthquakes, based on the data of seismic observation devices mounted on constructions with typical characteristics, results of investigating the change of mechanical properties of building structural system over time and the results of examination of structural rigidity and safety change over time, depending on the dynamic characteristics of the building, determined by experimental investigations made at intervals are mentioned in this article. In addition, evaluation of earthquake acceleration acting on structures due to earthquake-induced damage characteristics of buildings and engineering constructions which are made earthquake resistant is also included here.
文摘Construction of mass concrete structures face more challenges in temperature difference and complex stress under low temperature than the ambient temperature. It has been proved by the practice that, not only improving tensile strength of structural concrete as soon as possible and removing of constrain as much as possible, but also calculation of the thermal stress in the process of construction and maintenance, controlling structure of concrete tensile strength and temperature difference stress ratio can ensure the safety and defect-free.
文摘This article uses the age-structure/life-cycle method to analyze the impact of migrant workers’ employment on their urbanization. Since enterprises tend to employ younger workers and unemployed migrant workers tend to be middle-aged, we first apply the age structure/life cycle model to carry out our estimations, pointing out that in order to complete the urbanization of their families, migrant worker couples usually have to work for thirty years consecutively after marriage. On this basis, the article constructs a working life table for migrant workers and uses it to estimate the total quantity of Chinese migrant workers who have the minimum economic capacity required for urbanization. Taking into consideration future changes in the age structure of enterprise employment, we estimate that over the sixty-nine million migrant workers who were under thirty years old in 2006, together with their families, would already be in possession of the minimum economic conditions for settling in urban areas.
