Large scale biaxial tensile test on overall mechanicalproperties of HDPE geocell(PDF)
长安大学学报(自然科学版)[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2021年6期
- Page:
- 29-38
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Large scale biaxial tensile test on overall mechanicalproperties of HDPE geocell
- Author(s):
- MA Jia1; 2; SONG Ling1; LIU Jie1; 2; WANG Bin2; CHEN Shi3
- (1. College of Water and Architectural Engineering, Shihezi University, Shihezi 832003, Xinjiang, China;2. Xinjiang Transportation Planning Surveying and Design Institute, Urumqi 830000, Xinjiang, China;3. Lanzhou Deke Engineering Materials Co., Ltd, Lanzhou 730000, Gansu, China)
- Keywords:
- road engineering; subgrade engineering; geocell; biaxial tensile test; strip; node; mechanical property
- PACS:
- -
- DOI:
- -
- Abstract:
- To study the mechanical properties and deformation law of geocell materials, several groups of high density polyethylene (HDPE) geocells with different sizes were selected for tensile test. Firstly, the tensile tests of strips with different heights were carried out by universal testing machine to study the effect of height on strip strength. Then, the joints of geocell with different heights were stretched by joint tensile testing machine, and the relationship between strip strength and joint strength was studied. Finally, through the selfdeveloped biaxial tensile test device, the PIV system and electron microscope test were used to carry out the largescale biaxial tensile test of geocell, and the mechanical characteristics models of overall strength and strip strength were proposed.The results show that the overall deformation of HDPE geocell includes node deformation and strip deformation, the strip elongation and overall elongation of geocell have synergy, but the strip elongation is less than the overall elongation, and when the former is fixed, the overall elongation of geocell with higher height is larger. The overall strength of geocell is related to the joint strength and strip strength. The higher the height is, and the more number of joints per linear meter is, the higher the overall strength of geocell is. In the biaxial tensile test, the failure of the joint precedes that of the strip. Therefore, the failure strength of the geocell is determined by the strength of the joint. After the tensile failure, the strip is distributed in the same direction as the tensile direction, and the joint is in a multilayer tearing state. The electron microscope test also confirms this view. In engineering design, the selection of geocell design strength should pay attention to the matching relationship between node strength and strip strength. 2 tabs, 12 figs, 26 refs.
Last Update: 2021-12-14