Journal of Changjiang River Scientific Research Institute ›› 2025, Vol. 42 ›› Issue (1): 144-151.DOI: 10.11988/ckyyb.20230841

• Rock-Soil Engineering • Previous Articles     Next Articles

Large-scale Indoor Direct Shear Test on Fiber-reinforced Loess in Consideration of Distribution Effect

LIU Xin1,2(), XU Wei-neng1, HUANG Guang-jing1(), LAN Heng-xing1,3   

  1. 1 School of Geological Engineering and Surveying and Mapping,Chang’an University,Xi’an 710054,China
    2 Key Laboratory of Ecological Geology and Disaster Prevention of Ministry of Natural Resources, Chang’an University, Xi’an 710054, China
    3 State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
  • Received:2023-08-03 Revised:2023-09-19 Published:2025-01-01 Online:2025-01-01
  • Contact: HUANG Guang-jing

Abstract:

To investigate the effects of polypropylene fiber length, content, and distribution on loess reinforcement, a large-scale indoor direct shear test was designed for both uniform and non-uniform reinforcement schemes. In the non-uniform reinforcement, the fiber content was varied on both sides of the shear box and rammed into the soil in three layers. The curves of shear strength versus shear strain and shear strength indices of the reinforced loess were obtained. The results indicate: 1) Incorporating polypropylene fibers significantly enhances loess shear strength, with the reinforcement effect influenced by fiber length, dosage, and normal stress coupling. 2) In the uniform reinforcement scheme, a fiber length of 12 mm and a content of 0.5% achieves the best reinforcement effect. In the non-uniform reinforcement scheme, the influence range of the shear plane is less than 15 mm at normal stress of 50 kPa, slightly greater than 35 mm at 100 kPa, and further increased at 200 kPa. 3) The distribution pattern of fibers significantly impacts the reinforcement effect. Compared to a uniform 0.8% content group, non-uniform reinforcement with 0.5% content on both sides yields better results, as it avoids fiber agglomeration and ensures soil-fiber adhesion. These findings are expected to provide valuable insights for optimizing loess fiber reinforcement.

Key words: fiber-reinforced loess, large-scale indoor direct shear test, non-uniform reinforcement, influence range of shear surface, fibre distribution, shear strength, optimized reinforcement

CLC Number: