Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becomi...Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becoming an important social concern to develop and put to practical use simple and efficient health monitoring systems for existing short and medium span (10 - 30 m) bridges. In this paper, one practical solution to the problem for condition assessment of short and medium span bridges was discussed. A vehicle-based measurement with a public bus as part of a public transit system (called “Bus monitoring system”) has been developed to be capable of detecting damage that may affect the structural safety of a bridge from long term vibration measurement data collected while the vehicle (bus) crossed the target bridges. This paper systematically describes how the system has been developed. The bus monitoring system aims to detect the transition from the damage acceleration period, in which the structural safety of an aged bridge declines sharply, to the deterioration period by continually monitoring the bridge of interest. To evaluate the practicality of the newly developed bus monitoring system, it has been field-tested over a period of about four years by using an in-service fixed-route bus operating on a bus route in the city of Ube, Yamaguchi Prefecture, Japan. The verification results thus obtained are also described in this paper. This study also evaluates the sensitivity of “characteristic deflection”, which is a bridge (health) condition indicator used by the bus monitoring system, in damage detection. Sensitivity of “characteristic deflection” is verified by introducing artificial damage into a bridge that has ended its service life and is awaiting removal. As the results, it will be able to make a rational long-term health monitoring system for existing short and mediumspan bridges, and then the system helps bridge administrators to establish the rational maintenance strategies.展开更多
In order to ensure the construction quality and safety of small and medium span basket type steel box tied arch bridge,this paper takes a practical project as an example to analyze the key technologies in its design p...In order to ensure the construction quality and safety of small and medium span basket type steel box tied arch bridge,this paper takes a practical project as an example to analyze the key technologies in its design process.It is hoped that this analysis can provide corresponding reference for the design and construction of this kind of arch bridge.展开更多
A series of problems about Chinese bridges with short and medium span recent years were analyzed in this paper. The necessity and feasibility of modern timber structure applied in short and medium span bridges in Chin...A series of problems about Chinese bridges with short and medium span recent years were analyzed in this paper. The necessity and feasibility of modern timber structure applied in short and medium span bridges in China were also put forward. The results showed that the short and medium span bridges had many problems, such as monotonous structural forms, seri- ous environmental pollution, multiple bridge defects and difficulty in maintenance. With the development of connection and maintenance technology of modern timber structure and its ad- vantages of light self-weight, environmental coordination, high carrying capacity, excellent durability and abundant structural forms, it was necessary and feasible to apply modern timber structure in short and medium span bridges in China. More emphasis on the construction of modern timber structure should be conducted to expand its application scopes and improve the construction proportion of short and medium span timber bridges.展开更多
文摘Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becoming an important social concern to develop and put to practical use simple and efficient health monitoring systems for existing short and medium span (10 - 30 m) bridges. In this paper, one practical solution to the problem for condition assessment of short and medium span bridges was discussed. A vehicle-based measurement with a public bus as part of a public transit system (called “Bus monitoring system”) has been developed to be capable of detecting damage that may affect the structural safety of a bridge from long term vibration measurement data collected while the vehicle (bus) crossed the target bridges. This paper systematically describes how the system has been developed. The bus monitoring system aims to detect the transition from the damage acceleration period, in which the structural safety of an aged bridge declines sharply, to the deterioration period by continually monitoring the bridge of interest. To evaluate the practicality of the newly developed bus monitoring system, it has been field-tested over a period of about four years by using an in-service fixed-route bus operating on a bus route in the city of Ube, Yamaguchi Prefecture, Japan. The verification results thus obtained are also described in this paper. This study also evaluates the sensitivity of “characteristic deflection”, which is a bridge (health) condition indicator used by the bus monitoring system, in damage detection. Sensitivity of “characteristic deflection” is verified by introducing artificial damage into a bridge that has ended its service life and is awaiting removal. As the results, it will be able to make a rational long-term health monitoring system for existing short and mediumspan bridges, and then the system helps bridge administrators to establish the rational maintenance strategies.
文摘In order to ensure the construction quality and safety of small and medium span basket type steel box tied arch bridge,this paper takes a practical project as an example to analyze the key technologies in its design process.It is hoped that this analysis can provide corresponding reference for the design and construction of this kind of arch bridge.
基金supported by National Natural Science Foundation of China(NSFC)(No.51378068)
文摘A series of problems about Chinese bridges with short and medium span recent years were analyzed in this paper. The necessity and feasibility of modern timber structure applied in short and medium span bridges in China were also put forward. The results showed that the short and medium span bridges had many problems, such as monotonous structural forms, seri- ous environmental pollution, multiple bridge defects and difficulty in maintenance. With the development of connection and maintenance technology of modern timber structure and its ad- vantages of light self-weight, environmental coordination, high carrying capacity, excellent durability and abundant structural forms, it was necessary and feasible to apply modern timber structure in short and medium span bridges in China. More emphasis on the construction of modern timber structure should be conducted to expand its application scopes and improve the construction proportion of short and medium span timber bridges.
