Investigation of Mechanical Properties of Interface between Geogrid and Calcareous Sand with Different Particle Sizes Considering Temperature Effect

Abstract

Ensuring the safety of geotechnical engineering structures composed mainly of calcareous sand is critical. The high-temperature climate, stress loading, and soil particle dimension have non-negligible effects on the interaction between calcareous sand and geosynthetic, which determines the stability of calcareous sand engineering facilities for the placement of geosynthetics. In this paper, a self-developed temperature-controlled large-size interface device was used to conduct a series of pullout tests on geogrid-calcareous sand interface with particle sizes of 0.25mm ~ 1mm (S1 sand), 1mm ~ 2mm (S2 sand), 2mm ~ 4mm (S3 sand), and geogrid-Fujian standard sand interface with particle size of 1mm ~ 2mm (S4 sand) at temperatures of 0°C ~ 80°C. The effect of temperature on the mechanical properties of geogrid-calcareous sand/ Fujian standard sand interface (GRCS/GRFS) was investigated. The test results show that the interface shear strength and interface friction angle of GRCS and GRFS decrease with the increase of temperature. Notably, the maximum shear strength of the GRCS and GRFS interface occurs at 0°C. For the GRCS interface, the interface shear strength rises with the particle size increases. Temperature has a greater effect on the relative breakage ratio  than the fractal dimension. The shear strength of the GRCS interface greatly exceeds that of the GRFS interface. Based on the experimental results, a constitutive model of the soil-geogrid interface under pullout loading was established considering the effect of temperature. The results of this study provide a reference for the selection of mechanical parameters related to the GRCS interface in geotechnical engineering.

Keywords: Geogrid, Calcareous sand, Pullout test, Temperature