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The use of waste polyethylene terephthalate (PET) plastics derived from shredded bottles in concrete is not formalized yet, especially in reinforced members such as beams and columns. The disposal of plastic wastes in concrete is a viable alternative to manage those wastes while minimizing the environmental impacts associated to recycling, carbon dioxide emissions and energy consumption.

This paper evaluates the suitability of 2D deterministic and stochastic finite element (FE) modeling to predict the shear strength behavior of reinforced concrete (RC) beams without stirrups. Different concrete mixtures prepared with 1.5%–4.5% PET additions, by volume, are investigated.

Test results showed that the deterministic and stochastic FE approaches are accurate to assess the maximum load of RC beams at failure and corresponding midspan deflection. However, the crack patterns observed experimentally during the different stages of loading can only be reproduced using the stochastic FE approach. This later method accounts for the concrete heterogeneity due to PET additions, allowing a statistical simulation of the effect of mechanical properties (i.e. compressive strength, tensile strength and Young’s modulus) on the output FE parameters.

Data presented in this paper can be of interest to civil and structural engineers, aiming to predict the failure mechanisms of RC beams containing plastic wastes, while minimizing the experimental time and resources needed to estimate the variability effect of concrete properties on the performance of such structures.

The purpose of this study is to introduce a new concept in engineered materials and that is truss substructured materials (TSMs). These materials would be engineered to express mechanical abilities that are seldom found in nature.

This article starts with defining TSMs and how to classify and name TSMs. The article also introduces the theoretical modeling of TSMs, the software developed for analyzing TSMs and the parametric studies performed.

After these studies, new materials are introduced that have abilities such as negative Poisson ratio in X and Y direction, negative Poisson ratio in one direction (either x or y), self-remodeling under stress.

The research is done in 2D, further studies in 3D using 3D printing are required to make the suggested materials a viable real-world solution.

The main contribution of this research work is the proposed nomenclature that creates a system for researchers to experiment and create novel and unique versions of the proposed materials. Furthermore, some of the materials developed exhibit some unique properties that may create advances in engineering with further development.