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• Setting time and engineering properties of BCSA concrete are studied. • Citric acid delays initial set from 15 min to as long as 3.5 h. • Retarding hydration does not affect the mechanical strength. • Design codes accurately predict the modulus of elasticity and tensile strength. This paper discusses the setting time and engineering properties (compressive strength, tensile strength, and modulus of elasticity) of belitic calcium sulfoaluminate (BCSA) cement and concrete. BCSA is an emerging alternative cement known for, among other things, its rapid setting behavior. This has long supported its use as a concrete repair material, but BCSA is also attractive for structural applications. Nevertheless, little information is available on the engineering properties of BCSA concrete. This paper quantifies the influence of mixture parameters on BCSA cement setting times, showing that they can be tightly controlled by altering the dosage of a citric acid retarder. It also quantifies the influence of mixture parameters and curing age on compressive strength, proposing predictive models and showing that retarding the hydration of BCSA does not affect its long-term strength. Finally, this paper measures the modulus of elasticity and tensile strength of BCSA concrete and attempts to predict these properties based on the compressive strength. Results suggest that predictive equations from ACI 318, CSA A23, and Eurocode-2 tend to predict the engineering properties of BCSA cement rather well. Together, these results support the feasibility of integrating BCSA cement into practical concrete construction. [ABSTRACT FROM AUTHOR]

The composite material TRC results from the combination of a fine-grained cement matrix and a textile reinforcement. This composite has good mechanical properties and, depending on the nature of the matrix, good acoustic isolating properties and fireproofing can be considered. One of the potential applications of this new generation composite deals with sandwich panels via thin facings. Although studies of TRC sandwich panels are rare, it is the finite element approach which is quite preferred for studying their quasi-static mechanical behavior. Although interesting and useful, this approach requires excellent mastery of computer software given the many nonlinearities that should be included. This paper aims to provide a non-linear calculation procedure of TRC-facings sandwich panels with the following main properties: (i) the use of materials “real” behavior law (ii) the use of numerical methods (iii) the application of arbitrary combination loads and (iv) allowing to study both global and local behavior. This procedure is based on (i) the cross-section and length of the panel meshing and (ii) the non-coupling of bending, shear and local bending effects of the mechanical behavior of the panel. A sensitivity study is further performed to evaluate the evolution of the relative error depending on the mesh size. Finally, using the results obtained from an experimental campaign on TRC-facings sandwich panels, a theoretical/experimental confrontation on a global scale (load-deflection behavior and failure mode) and local (strain development) will be performed. This will permit us, on one hand, to emphasize the good reproduction of the results given by the method on a global scale and, on the other hand, some limitations to the local scale where possible explanations are proposed. [ABSTRACT FROM AUTHOR]