Strain gauge based microsensor for stress analysis in building structures

An important element in the supervision of buildings is the necessary precise and continuous measurement of stress conditions. For this purpose, an encapsulated measuring sensor has been developed which encloses and protects the sensitive strain gauge technology and can be easily inserted into measurement boreholes.The mechanical adaptation is effected by optimising the process of deformation of two conical bodies such that the envisaged measuring range covers the range of elastic deformation of construction steels. Suitable calibration procedures, as well as measurement methods for the early detection of structural damage in buildings, were developed for this adaptation model. A strain gauge layout adapted to the specific local conditions was devised for the sensor, and the strain gauge is protected by a plastic seal. In order to be able to assess the lifetime of the sealing materials, which in part were being employed for the first time, the chemical/climatic building environment was simulated under forced conditions in the laboratory.