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Early detection of damage has emerged as an important concern for engineers involved in structural condition assessments. This paper presents a damage detection approach that combines different techniques to improve detection and localization of small increments of damage using mode shapes derived from vibration tests on a structure. An experimental study is carried out on a beam with two joints that can simulate incremental damage with a system of plates and bolts. The initial condition is defined as the state when the plates are fully assembled. In this state, the beam comprises two weaker zones at the location of each joint assembly due to a 12% reduction in stiffness in comparison to an intact beam. The test setup is used to simulate incremental damage by modifying the mass and stiffness of the beam at each joint. The proposed method of detection is shown to outperform current alternative methods in detecting small increments of damage and to result in fewer false alarms. The detection procedure comprises four steps: (1) a continuous wavelet transform to detect local anomalies in the first mode shape; (2) a principal component analysis of wavelet coefficients to extract dominant patterns that are most highly correlated with incremental damage and to reduce noise; (3) statistical tests of hypothesis on the scores of principal components to detect statistically significant incremental damage, and (4) a likelihood ratio test to determine the most likely location of incremental damage along the beam.

The linear polarisation resistance (LPR) technique is increasingly being implemented to assess the corrosion rate of steel reinforcements in concrete. However, a lack of reliability is often observed experimentally. In order to improve the physical comprehension of the LPR technique, FEM simulations were performed. Several measurement devices using annular and rectangular probe geometries were simulated and the numerical experimentation allowed the relevance of RILEM recommendations for on-site measurements to be tested. It was shown that the LPR measurement using annular counter-electrodes with confining devices was a real three-dimensional physical problem and the non-uniform distribution of the polarising current on the steel surface is actually a major source of error since it is not taken into account by the usual protocols. Moreover, it was found that some complexity was induced by the use of guard-rings. La technique de resistance de polarisation lineaire (Rp) est utilisee de plus en plus frequemme...

International audience; Currently, over 90% of goods are transported by road terrestrial mode. To progress, companies of Road Freight Transport sector (RFT) are subject to a number of issues, whether economic, regulatory, environmental, societal, occupational health and safety ... The planner has a crucial role in achieving these challenges, it is he who undertakes the construction method of the tours, for the future of the company. Thus he bears a heavy responsibility on his shoulders. Its ability to integrate the company’s constraints and to master the balance between these issues in the construction of tour is vital. However, a list of risks is potentially present and can affect his planning. This lack of vision about risks impact prevents him to achieve his mission. Thus we propose in this article a mean to qualify the tours generated in relation to the issues mentioned but also in terms of potential hazards that could come impair the quality of tours. In this article, we propose an evaluation process of road transport of goods tours and an indicator to measure the robustness of touring.