This paper aims to present a theoretical method to study the bearing performance of vertically loaded large-diameter pipe pile groups.The interactions between group piles result in different bearing performance of bot...This paper aims to present a theoretical method to study the bearing performance of vertically loaded large-diameter pipe pile groups.The interactions between group piles result in different bearing performance of both a single pile and pile groups.Considering the pile group effect and the skin friction from both outer and inner soils,an analytical solution is developed to calculate the settlement and axial force in large-diameter pipe pile groups.The analytical solution was verified by centrifuge and field testing results.An extensive parametric analysis was performed to study the bearing performance of the pipe pile groups.The results reveal that the axial forces in group piles are not the same.The larger the distance from central pile,the larger the axial force.The axial force in the central pile is the smallest,while that in corner piles is the largest.The axial force on the top of the corner piles decreases while that in the central pile increases with increasing of pile spacing and decreasing of pile length.The axial force in side piles varies little with the variations of pile spacing,pile length,and shear modulus of the soil and is approximately equal to the average load shared by one pile.For a pile group,the larger the pile length is,the larger the influence radius is.As a result,the pile group effect is more apparent for a larger pile length.The settlement of pile groups decreases with increasing of the pile number in the group and the shear modulus of the underlying soil.展开更多
We analyze an infinite horizon difference game between four aggregated industries-production of producer goods, production of consumption goods, federation of labor unions, and commercial banking sector. Consumers do ...We analyze an infinite horizon difference game between four aggregated industries-production of producer goods, production of consumption goods, federation of labor unions, and commercial banking sector. Consumers do not behave strategically. They make their decisions on the basis of maximization of average discounted utility. Therefore, we do not include them in the set of players in the game. The payoffof each production industry and the commercial banking sector is equal to the average discounted sum of real dividends of its owners. The payoff of the federation of labor unions is equal to the average discounted sum of real wages and real unemployment benefits. A strict strong perfect general equilibrium is the applied solution concept for the game. It requires that there does not exist a coalition of players that can weakly Pareto improve the vector of continuation payoffs of its members in some subgame by a coordinated deviation. It is a refinement of Rubinstein＇s concept of a strong perfect equilibrium. We formulate and prove the sufficient condition for its existence. It is based on the assumption that no one of the aggregated industries can have a positive output without using some minimal amount of output of each other aggregated industry as an input. By definition, in each subgame, the equilibrium payoff vector in a strict strong perfect general equilibrium is strictly Pareto efficient. Thus, if each consumer either has only income from wage and unemployment benefit or receives dividend from only one aggregated industry, and his nominal income in each period along the equilibrium path exceeds social minimum, it is not possible to weakly Pareto improve the vector of consumers＇ average discounted real incomes. This holds not only for the whole game but also for each subgame starting in the first phase of some period.展开更多
基金supported by the Joint High Speed Railway Key Program of National Natural Science Foundation of China (Grant No.U1134207)the National Natural Science Foundation of China (Grant No.51378177)+1 种基金the Program for Excellent University Talents in New Century (Grant No.NCET-12-0843)the Fundamental Research Fund for the Central Universities (Grant No.106112014CDJZR200007)
文摘This paper aims to present a theoretical method to study the bearing performance of vertically loaded large-diameter pipe pile groups.The interactions between group piles result in different bearing performance of both a single pile and pile groups.Considering the pile group effect and the skin friction from both outer and inner soils,an analytical solution is developed to calculate the settlement and axial force in large-diameter pipe pile groups.The analytical solution was verified by centrifuge and field testing results.An extensive parametric analysis was performed to study the bearing performance of the pipe pile groups.The results reveal that the axial forces in group piles are not the same.The larger the distance from central pile,the larger the axial force.The axial force in the central pile is the smallest,while that in corner piles is the largest.The axial force on the top of the corner piles decreases while that in the central pile increases with increasing of pile spacing and decreasing of pile length.The axial force in side piles varies little with the variations of pile spacing,pile length,and shear modulus of the soil and is approximately equal to the average load shared by one pile.For a pile group,the larger the pile length is,the larger the influence radius is.As a result,the pile group effect is more apparent for a larger pile length.The settlement of pile groups decreases with increasing of the pile number in the group and the shear modulus of the underlying soil.
文摘We analyze an infinite horizon difference game between four aggregated industries-production of producer goods, production of consumption goods, federation of labor unions, and commercial banking sector. Consumers do not behave strategically. They make their decisions on the basis of maximization of average discounted utility. Therefore, we do not include them in the set of players in the game. The payoffof each production industry and the commercial banking sector is equal to the average discounted sum of real dividends of its owners. The payoff of the federation of labor unions is equal to the average discounted sum of real wages and real unemployment benefits. A strict strong perfect general equilibrium is the applied solution concept for the game. It requires that there does not exist a coalition of players that can weakly Pareto improve the vector of continuation payoffs of its members in some subgame by a coordinated deviation. It is a refinement of Rubinstein＇s concept of a strong perfect equilibrium. We formulate and prove the sufficient condition for its existence. It is based on the assumption that no one of the aggregated industries can have a positive output without using some minimal amount of output of each other aggregated industry as an input. By definition, in each subgame, the equilibrium payoff vector in a strict strong perfect general equilibrium is strictly Pareto efficient. Thus, if each consumer either has only income from wage and unemployment benefit or receives dividend from only one aggregated industry, and his nominal income in each period along the equilibrium path exceeds social minimum, it is not possible to weakly Pareto improve the vector of consumers＇ average discounted real incomes. This holds not only for the whole game but also for each subgame starting in the first phase of some period.
