Finite strip modeling of cementitious laminates reinforced with sisal fibers

The use of natural fibers to reinforce of cementitious matrices permits the development of sustainable materials with many potential applications. However, the improvement of such materials strongly depends on experimental studies, making the process slow and expensive. The numerical methods currently available for modeling composites can adequately describe the behavior of polymeric laminates, but have limited application in cementitious laminates that can have multiple cracking. This paper proposed a numerical model that combines the Finite Strip Method, Classical Theory of Laminates and Damage Mechanics to model the flexural behavior of laminated composites. The method can monitor the stresses developed in each layer and verify the ruptures resulting from traction, compression or shear. To validate the numerical method, flexural tests were carried out on cementitious laminates reinforced with 2 or 3 layers of long sisal fiber, with fiber content of 3% or 6%. Comparisons between the numerical and experimental results demonstrate good agreement, especially for composites reinforced with high fiber content. The adequate prediction of internal stress allows for the use of this numerical method to design cementitious laminates reinforced with sisal fibers that possess properties suitable for various applications.