By adopting natural excitation technique and mathematical statistics theory,a damage index is established,which is based on the strain measurement of structures under environmental excitation.

Strain measurements and stress analysis of unit-2 reactor pressure vessel of QinShan nuclear power plant phase II were successfully performed at shop hydrostatic test with domestic technology.

A strain measurement system was developed based on LabVIEW,a popular workbench for Virtual Instruments to rapidly and exactly make measurement and analysis using computers.

Taking the deep foundation pit of Jinmao Building supported by steel pipes as a practical example, the analyses on the three results such as the strain test of steel pipes, the observation deformation and crack and monitoring of displacement were made in the paper.

A strain test system based on RS485 bus has been introduced for the stress monitor in the process of equipment-hoisting.

The paper firstly introduces the strain test of TianJin Museum long-spanreticulated shell and makes out the structural stress response, ensuring the securityof the structural construction.

The pile tip resistance and pile shaft resistance can be calculated by using the strain testing,which provides a good reference for the design of popularly application for the bridge approach project of Wuhan Tianxinzhou road Railway Bridge using AM bulb cast-in-place piles.