Stress ribbon bridges have many advantages and became recently more popular mostly because of their versatile form, slender decks giving a light aesthetic impression and durability assured by post tensioned concrete. ...Stress ribbon bridges have many advantages and became recently more popular mostly because of their versatile form, slender decks giving a light aesthetic impression and durability assured by post tensioned concrete. The paper presents the first in Poland stress Ribbon Bridge constructed last year. A static and dynamic analyse of the model is presented as well as construction solutions which were used to achieve the highest durability. The bridge was checked during static and dynamic load test. The results of this prove test were compared with results obtained from examination and study of other different bridge structures. It confirmed that the bridge has good dynamic resistance and greater stiffness than assumed in the design.展开更多
In this paper, we establish a mathematical model of two species with stage structure and the relation of predator-prey, to obtain conditions that determine the stability of the populations. By the application of compa...In this paper, we establish a mathematical model of two species with stage structure and the relation of predator-prey, to obtain conditions that determine the stability of the populations. By the application of comparing argument and exploiting the monotonicity of one equation of the model, we obtain sufficient conditions for the global attractiveness of positive equilibrium .展开更多
文摘Stress ribbon bridges have many advantages and became recently more popular mostly because of their versatile form, slender decks giving a light aesthetic impression and durability assured by post tensioned concrete. The paper presents the first in Poland stress Ribbon Bridge constructed last year. A static and dynamic analyse of the model is presented as well as construction solutions which were used to achieve the highest durability. The bridge was checked during static and dynamic load test. The results of this prove test were compared with results obtained from examination and study of other different bridge structures. It confirmed that the bridge has good dynamic resistance and greater stiffness than assumed in the design.
基金This work is supported by National Natural Science Foundation of China （10371105） and the NSF of Henan Province （031000）
文摘In this paper, we establish a mathematical model of two species with stage structure and the relation of predator-prey, to obtain conditions that determine the stability of the populations. By the application of comparing argument and exploiting the monotonicity of one equation of the model, we obtain sufficient conditions for the global attractiveness of positive equilibrium .
