A review of 3D-printed architected polymer structures as reinforcement in cementitious applications

Abstract

Additive manufacturing of architected polymer reinforcements is an emerging geometry-driven approach to improve the mechanical performance of cementitious materials. In contrast to conventional methods, it enables controlled architectures where load transfer and crack propagation are governed by topology and spatial distribution. However, comparisons are difficult due to variability in architectures, materials, processes and testing conditions. This review covers advances in 3D-printed polymer reinforcements, such as discrete and graded lattices, TPMS, auxetic, and origami-inspired structures. The reported improvements are mainly related to ductility, post-cracking response, energy absorption (up to 853%) and flexural toughness (up to 23×), with some systems showing a transition toward strain-hardening behavior. However, these values are strongly influenced by the baseline reference conditions, reinforcement ratio, polymer type, architecture, specimen geometry and testing protocol, limiting direct quantitative comparison between studies. The effects of polymer selection and manufacturing processes are also discussed. The main challenges are geometric inaccuracies, limited interface characterization, insufficient durability assessment, and lack of standard protocols. To address these, better interface design, material selection, and consistent processing–structure–property analysis are needed, which would support a more rational design framework and broader applications.