Axial stress-strain models for grouted dry-stack concrete block masonry

The stress-strain relationship of construction materials and their mechanical parameters under axial compression are essential for designing structural elements. However, the stress-strain relationship of dry-stack masonry, especially grouted dry-stack concrete masonry, which is widely used in Australasia and North America, remains not well explored. This study has developed a unified set of formulations to evaluate the stress-strain relationship of grouted dry-stack concrete masonry. An experimental database of grouted dry-stack concrete masonry tested under axial compression was created to verify the appropriateness of available stress-strain models for dry-stack and conventional concrete block masonry. The predictabilities of peak compressive strength and strain at peak strength formulations were initially evaluated and subsequently optimised using the Bayesian optimisation technique. These optimised formulations were then used to assess proposed stress-strain models for dry-stack concrete block masonry. Then those stress-strain models were optimised using the Bayesian optimisation technique for improved prediction of the stress-strain response of grouted dry-stack concrete masonry. The proposed stress-strain model is shown to predict closely against the experimental database with reasonable magnitudes of least model error, root mean square error, and coefficient of variations.