Experimental Study on the Influence of Slurry Concentration and Standing Time on the Friction Characteristics of a Steel Pipe-Soil Interface

Applied Sciences

Anfeng Xiao¹  Kaixin Liu¹  Cong Zeng¹  Zhihan Chen¹  Peng Zhang¹  Hui Ai² 

[1] Faculty of Engineering, China University of Geosciences (Wuhan), Wuhan 430074, China;Nuclear Industry JingXiang Construction Group Co., Ltd., Huzhou 313000, China;

关键词: pipe jacking;    direct shear test;    friction characteristics;    slurry concentration;    slurry standing time;   

DOI  :  10.3390/app12073576

来源: DOAJ

【 摘 要 】

In pipe jacking, the continued growth of friction resistance around the pipe may cause problems, such as an insufficient jacking force, soil collapse, and even land subsidence, which seriously endangers the structural safety of the pipe and surrounding structures. Bentonite slurry is often used as a lubrication material, but the friction resistance increases due to the inappropriate slurry concentration, and this may cause construction safety problems. In addition, the slurry standing time increases the difficulty of re-jacking construction. To further study the above problems, the friction characteristics of a steel pipe-soil interface under different slurry concentrations and slurry standing times were studied using direct shear tests. The test results show that the peak shear stress and friction coefficient of the interface first decrease and then increase with the increase in the concentration, which is less than or equal to 20%. The peak shear stress and friction coefficient increase with the increase in the concentration, which is greater than 20%, and the position of shear failure changes from between the slurry soil mixture and pipe wall to between the slurry and pipe wall, and finally to the slurry interior. The influence of the slurry standing time on the friction characteristics of the interface is as follows: For the same slurry concentration, the peak shear stress and friction coefficient of the interface increase with the standing time, approximately increasing first and then stabilizing; for different slurry concentrations, the amplification of the peak shear stress and friction coefficient increase with the increase in the concentration.

【 授权许可】

Unknown