Review of some nondestructive methods for dmage detection in concrete structures

The weak point in structural elements reduces the durability of structures and irreparable damage received from natural disasters like earthquake or other kind of degradation factors such as temporal attacts, constructing errors. In economical point of view reconstructing grand structurs needs strong budjets whereas, rehabilitating needs lower ons. Therfore, rehabilitation is prefered in civil engineering. The most important factor, which is concerned rehabilitation, is identification of possible failures and strength of structural elements. Particularly, concrete structures suffer more than other materials because of the dichotomy medium and uncertainties caused by internal reactions. Furthermore, reducing uncertainties could not be implemented easily. Multi-channel analysis of surface wave method has gained popularity in engineering practice for determining homogeneity in depth profiles of soil and concrete structures. This paper sifts through common nondestructive test (NDT) technics in charge of seismic methods F-K method furthermore, proposed Power Spectral Density (PSD) method and Attenuation Analysis of Rayleigh Wave (AARW) method which are particularly used for soil structures, which has the ability to use in this field of engineering, for detecting voids and zone degradation in concrete structures. the PSD method was appreciated in this paper since high accuracy and ease of usage. Although hand peaking of the location of the inhomogeneities is avoidable for important structures, in field of NDT proccedure of application consists of several methods to locate the anomaly and the final check was assigned by the most sensetive method. The time saving and defect resolution of the method are important reasons to consider this method as a high level of sensetive category

Keywords:

MASW , PSD , AARW , concrete structures , NDT