Deformation Characteristics of Multilayered Self‐Balanced Arched Lattice Truss Structures Under Compression and Bending

ABSTRACT This paper investigates the deformation characteristics and energy absorption (EA) performance of multilayered self‐balanced arched lattice truss structures under compressive and bending. To address the common issues of local stress concentration and instability in traditional arch designs, an optimized structural form incorporating tension chords and actively bendable bars was proposed. Test specimens were fabricated using two different materials—thermoplastic polyurethane (TPU) and carbon fiber reinforced high‐temperature polyamide (PAHT‐CF15)—via additive manufacturing, and evaluated through flat compression and three‐point bending experiments. The TPU specimens exhibited stable overall deformation with a specific energy absorption (SEA) of 8.89 mJ/g and 8.68 mJ/g, indicating minimal sensitivity to specimen size. In contrast, the PAHT‐CF15 specimens achieved significantly higher SEA values, reaching up to 170.72 mJ/g (P4), with corresponding total EA as high as 63.92 J. Finite element modeling (FEM) of three‐point bending was conducted, showing good agreement with experimental results. Energy distribution analysis revealed that middle layers contributed the most to absorption prior to instability onset, confirming the designed deformation mechanism. These results demonstrate that the proposed self‐balanced arch structure effectively disperses stress, delays failure progression, and exhibits excellent EA across materials and scales. The findings offer promising guidance for the application of advanced lattice structures in lightweight protective, architectural, and impact‐resilient systems.