Comparison between different experimental techniques for stiffness monitoring of cement pastes

Abstract

In 2009, a new methodology for the continuous monitoring of E-modulus of cement-based materials since casting was proposed, under the designation EMM-ARM (E-modulus Measurement through Ambient Response Method). This methodology is a variant to classic resonant frequency methods that allows continuous stiffness monitoring from the instant of casting. After the encouraging results obtained in the first applications of EMM-ARM to cement pastes, the present paper gives continuity to previous developments, through validations with additional experimental methodologies and extension to thermal activation testing. At first, a comparison is performed between the results of EMM-ARM and those obtained through: pulse velocity methods (both ultrasonic contact probes and bender-extender elements), penetration resistance (Vicat needle) and cyclic compression on cylindrical specimens. Afterwards, the possibility of studying the activation energy of the stiffness evolution on tests conducted at 20°C and 40°C is explored.