Modelling the stress–dilatancy behavior of carbonate sand in Abu Dhabi

Carbonate sands are the primary material used in the construction of reclaimed islands in the United Arab Emirates (UAE). Their stress–strain behavior exhibits unique characteristics due to strong particle interlocking, which arises from their naturally angular platy shapes. This interlocking effect contributes to the distinctive dilatancy of carbonate sands and poses challenges in modeling their stress–dilatancy response using the conventional NorSand constitutive model. To address this, the NorSand model was extended by incorporating an additional material parameter to better capture their dilatancy behavior. The extended model was validated through consolidated drained triaxial compression tests conducted on carbonate sand collected from an artificial island in Abu Dhabi, UAE. Additionally, variations in model parameters were investigated by collecting experimental results of carbonate sands from various geographical regions. To assess parameters uncertainties, a Monte Carlo simulation was performed using conditional multivariate normal distributions. A systematic assessment demonstrates that the newly introduced material parameter plays a crucial role in accurately capturing the stress–strain response and regional behavior of carbonate sands.