Expansion properties of concrete with expansive additives (EAs) are dependent on the composition of the EAs and the nature of the external restraints. This study focuses on calcium sulfoaluminate (CSA) based EA, investigating their expansion behavior under uniaxial restraint conditions. This novel aspect of the work is highlighting the effect of restraint in one direction on the expansion in different directions (i.e. restraint and stress-free directions) as well as the overall volumetric expansion of concrete. The current work also compares the anisotropic expansion of concrete with CSA-based EA to the free lime-based EA. Experimental results reveal that the expansion of concrete in the restraint direction significantly reduces inducing stress in the concrete, while the other directions remain unaffected by the degree of restraint. The study introduces an anisotropic coefficient to quantify the effect of external restraint on expansion, showing a higher coefficient for CSA-based EA compared to free lime-based EA under similar restraint conditions. This study provides insights into the complex interplay between external restraint and expansion characteristics for CSA-based EA concrete.

@en

Fibre-metal laminates (FMLs) have been studied intensively for the past three decades because of their enhanced fatigue properties compared to monolithic metals. Most of these studies have focused on the fatigue damage under in-axis loading. These studies led to the application of FMLs in the aircraft structure in the early 21st century. However, the main application remains limited to the aircraft fuselage where the loading direction remains mostly constant. The few studies in the damage directionality of FMLs show that crack paths in FMLs under off-axis loading can undergo small deflections in biaxial GLAss REinforced aluminium (Glare) grades but show a significant amount of deflection in uniaxial Glare grades. In order to extend FML application to other parts of the aircraft structure where the loading direction is not constant or where uniaxial Glare is required – like aircraft wings - more understanding is required about the directionality of damage in FMLs under off-axis loading. To this effect the present research in damage directionality of FMLs under off-axis loading was undertaken.@en