Experimental Investigation on Failure Mechanisms of HDPE Welded Geocell Junctions under Different Clamping Distances

Abstract

Geocells are three-dimensional honeycomb-reinforced geotechnical materials composed of strips and junctions. Its junctions can support and transmit forces in several directions. The performance of geocells has a considerable impact on engineering applications. However, the testing program of geocell junctions still lacks standardization, and limited research has been undertaken regarding the failure mechanisms of junctions when subjected to various stress types. In this paper, four test procedures for HDPE welded geocell junctions were performed, including weld tensile, shear, peeling, and splitting strength tests. The influence of tests under different clamping distances (10.5 mm, 25 mm, 50 mm, and 100 mm) was analyzed, and the stress–strain behavior, peak elongation, and peak and residual strength of junctions under various force states were analyzed in detail. Finally, considering the strength and deformation, the slope laying method of geocells was proposed. The results show that the tensile strength and shear strength decrease with the clamping distance, whereas the peeling strength and splitting strength remain essentially unchanged. Under a 100 mm clamping distance, the tensile strength and shear strength are decreased by 4.51% and 14.08%. Geocells spreading vertically along the surface on a subgrade slope are thought to be more reliable, improving the geocell’s service life in slope protection. The test results can be used to improve a standardized geocell junction testing procedure as well as to guide, evaluate, and enhance the quality and application dependability of geocells.