An innovative approach for continuous measurement of cemented sand stiffness immediately after layer compaction

The application of a vibration-based methodology for continuous measurement of stiffness of cemented sand has been recently proposed by the authors of this work. Such methodology consists in placing the cemented sand sample into a mould, which is in turn placed in simply supported beam conditions, and monitored along time for assessment of the evolution of the resonant frequency of the system. The evolving resonant frequency of the system can be analytically correlated to the stiffness. Based on the success of the pilot application, this work extends the methodology towards in-situ sampling. Such extension involves the use of new geometries and materials for the moulds. The performance of the adapted technique is verified by comparing its results to those of obtained through uniaxial compression cyclic tests to up 28 days ageFundação para a Ciência e a Tecnologia (FCT