The “Structural Health Monitoring” is a project supported by National Natural Science Foundation for Distinguished Young Scholars of China(Grant No.50725828).To meet the urgent requirements of analysis and assessment of mass monitoring data of bridge environmental actions and structural responses,the monitoring of environmental actions and action effect modeling methods,dynamic performance monitoring and early warning methods,condition assessment and operation maintenance methods of key members are systematically studied in close combination with structural characteristics of long-span cable-stayed bridges and suspension bridges.The paper reports the progress of the project as follows.(1) The environmental action modeling methods of long-span bridges are established based on monitoring data of temperature,sustained wind and typhoon.The action effect modeling methods are further developed in combination with the multi-scale baseline finite element modeling method for long-span bridges.(2) The identification methods of global dynamic characteristics and internal forces of cables and hangers for long-span cable-stayed bridges and suspension bridges are proposed using the vibration monitoring data,on the basis of which the condition monitoring and early warning methods of bridges are developed using the environmental-condition-normalization technique.(3) The analysis methods for fatigue loading effect of welded details of steel box girder,temperature and traffic loading effect of expansion joint are presented based on long-term monitoring data of strain and beam-end displacement,on the basis of which the service performance assessment and remaining life prediction methods are developed. The “Structural Health Monitoring ” is a project supported by National Natural Science Foundation for Distinguished Young Scholars of China (Grant No. 50725828). To meet the urgent requirements of analysis and assessment of mass monitoring data of bridge environmental actions and structural responses , the monitoring of environmental actions and action effect modeling methods, dynamic performance monitoring and early warning methods, condition assessment and operation maintenance methods of key members are systematically studied in close combination with structural characteristics of long-span cable-stayed bridges and suspension bridges. The paper reports the progress of the project as follows. (1) The environmental action modeling methods of long-span bridges are established based on monitoring data of temperature, sustained wind and typhoon. The action effect modeling methods are further developed in combination with the multi-scale baseline finite element modeling method for long-span bridges (2) The identification methods of global dynamic characteristics and internal forces of cables and hangers for long-span cable-stayed bridges and suspension bridges are proposed using the vibration monitoring data, on the basis of which the the condition monitoring and early warning methods of bridges are developed using the environmental-condition-normalization technique. (3) The analysis methods for fatigue loading effect of welded details of steel box girder, temperature and traffic loading effect of expansion joints are presented based on long-term monitoring data of strain and beam-end displacement, on the basis of which the service performance assessment and remaining life prediction methods are developed.