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Abstract: This paper presents recent modifications of the Leak Before Break procedure of the A16 appendix from French RCC-MR nuclear code and the improvements that will be proposed. The first part of the study deals with the prediction of the crack size at penetration. In the case of small initial defect the validity of the Master Curve used in the A16 appendix is confirmed for pipes. For large initial defects, a correction to the A16 procedure is proposed to take into account the effect of large initial crack length on its size at penetration. The second part of this paper focuses on the crack shape evolution after penetration, which is characterized by two stages: first straightening of the crack shape and then crack growth at both inner and outer surfaces. This typical behaviour is confirmed by numerical and experimental works for which particular loading conditions have been investigated. [Copyright &y& Elsevier]

Abstract: Measurement of short-term and long-term deflections is a necessary step towards understanding and evaluating the status of a bridge. In this paper, a novel non-contact weighted-stretched-wire (NCWSW) system is developed for measuring the deflection of a bridge. Also some factors related to the system are addressed. The proposed system is promising due to some attractive features such as high precision, low implementation cost and suitability for continuous monitoring. The efficiency and reliability of NCWSW system are investigated both analytically and experimentally. A realistic NCWSW system has been used in the monitoring of a real-world bridge. [Copyright &y& Elsevier]

Abstract: In this paper, we study a boundary feedback system of a class of nonuniform undamped Timoshenko beam with both ends free. We give some sufficient conditions and some necessary conditions for the system to have exponential stability. Our method is based on the operator semigroup technique, the multiplier technique, and the contradiction argument of the frequency domain method. [Copyright &y& Elsevier]