Cement-bentonite is one of the main materials used in the seepage barriers to protect earth dams and levees from water erosion. However, the current understanding of the erodibility of the cementitious materials and the interactions between cracked seepage barriers and the water flow is inadequate. Based on the laboratory pinhole erosion test, we first investigated the impacts of cement-bentonite treatments by using the ground granulated blast-furnace slag (GGBS) as replacement on the erosion characteristics, compared with the original mixtures; the inclusion of GGBS highlighted a potential advantage against water erosion. In addition, we proposed to calculate the erosion percentage and establish the mathematical relationships between the erosion percentage and different regimes, that is, different curing period, erosion time, and sizes of initial holes. Results showed that enough curing period was critical to avoid the increases of hydraulic conductivity in the macrofabric of the barrier; meanwhile, the materials were eroded quickly at the beginning and slowed down with the erosion time, where the enlargement of the initial creaks would be stabilised at some point in time. Moreover, the sizes of initial holes may affect the erosion situation varying from the sample curing periods.
Bibliographical noteFunding Information:
This research has been supported by the State Key Program of National Natural Science Foundation of China (Grant no. U1434210), the National Natural Science Foundation of China (Grant no. 51778046), the National Natural Science Foundation of China (Grant no. 51278045), and the Project of Shen-zhen Metro Group Co., Ltd. (no. SZ-CGM-KY001/2014).
© 2017 Zijun Wang et al.
ASJC Scopus subject areas
- Materials Science(all)