Abstract
This report provides an overview over the most common used NDT methods and sensors for inspection and monitoring of existing concrete structures. The methods are briefly described with regard to their working principle and the parameters and properties of concrete structures that can be investigated. NDT methods are divided into three groups; a) optical b) mechanical and acoustic and c) electro-magnetic methods. The part on sensors is divided by the parameter to monitor, e.g. sensor for monitoring deformation, tilt, strain, cracks, vibrations, temperature, humidity, corrosion, pH, chloride, water pressure, etc. An own chapter deals with fibre optical sensors applicable for many different purposes.