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Geosynthetics are an effective method to increase the seismic level of reinforcement soil structures. In this paper, sensor-enabled geobelts (SEGB) that performed self-measurement and reinforcement functions were developed on the strain-sensitive electrical conductivity (tensoresistivity) of the high-density polyethylene (HDPE) filled with super conductive carbon black (CB). To study the influence of seismic loads on SEGB, a series of cyclic loading tests were performed. Before cyclic loading, different prestrains were applied to simulate the deformation of SEGB in soil before earthquake. The results show that the tensile strength and elongation at break of SEGB after cyclic loading decrease with the number of loading cycles and strain amplitude of cyclic load, though the prestrains have a limited influence on the reduction of mechanical properties of SEGB. For the tensoresistivity response of SEGB after cyclic loading, the electrical conductivity of SEGB becomes more sensitive to strain by increasing number of loading cycles, amplitude of cyclic load and prestrains. Based on the test results, a preliminary model was proposed to evaluate the tensoresistivity performance of SEGB after cyclic loading. [ABSTRACT FROM AUTHOR]

The durability of geosynthetics is important for their service life, transportation and long-term storage. This paper presents the effects of three accelerating degradation tests (thermal oxidation, UV radiation and corrosion) on the mechanical properties and tensoresistivity of a new smart geosynthetic material called sensor-enabled geobelt (SEGB), which is made by high-density polyethylene (HDPE) filled with carbon black (CB). Three characteristics obtained by two tensile tests with different loading speeds are considered to evaluate the durability of the SEGB: tensile strength, elongation at break and electrical resistance. The results show that the tensile strength and elongation at break decrease to different degrees. It indicates that the mechanical properties of the SEGB deteriorate after the three degradation tests. And the electrical resistance displays a sharp increase trend after the strain exceeds a certain number. That means the sensitivity of tensoresistivity improves. Furthermore, the degradation mechanism of the SEGB in the three degradation tests is demonstrated. And it indicates that the chain reactions trigger the change of these mechanical properties and the tensoresistivity of the SEGB. [ABSTRACT FROM AUTHOR]

• A new geosynthetic with a special sandwich structure named negative-Poisson's-ratio geobelt (NPRG) was designed. • The NPRG achieves a negative-Poisson's-ratio effect by changing its macrostructure. • The Poisson-like ratio variations and reinforcement behaviors of NPRG were investigated. • The NPRG can improve the overall reinforcement effect in soil due to its cross-sectional expansion. Reinforcement of elevated subgrades, embankments, or slopes is a focus of highway construction projects. In this study, a new negative-Poisson's-ratio geobelt (NPRG) is developed to facilitate such reinforcements. Herein, the NPRG design and manufacturing process are described in detail. Additionally, tensile tests, pull-out tests, and numerical simulations to test the negative-Poisson's-ratio effect and mechanical behavior of the NPRG in soil are reported. The results show that the NPRG shell structures are lifted by the core structure under tension, thereby expanding the NPRG cross-section. Hence, a negative-Poisson's-ratio effect is generated. Further results show that the negative-Poisson's-ratio effect of the NPRG only appears when the axial strain exceeds 1.2% or 1.6% (from the test and numerical simulation, respectively). Moreover, with 300 kPa as the boundary, the NPRG peak pulling force first increases and then decreases with increasing upper pressure. Finally, the negative-Poisson's-ratio effect of the NPRG disturbs the surrounding soil. Simultaneously, the NPRG cross-sectional expansion makes it more closely integrated with the surrounding soil, thereby, improving the reinforcement effect. [ABSTRACT FROM AUTHOR]