Grouting Process Simulation Based on 3D Fracture Network Considering Fluid–Structure Interaction

Abstract

Grouting has always been the main engineering measure of ground improvement and foundation remediation of hydraulic structures. Due to complex geological conditions and the interactions between the grout and the fractured rock mass, which poses a serious challenge to the grouting diffusion mechanism analysis, fracture grouting has been a research hotspot for a long time. In order to throw light on the grout diffusion process in the fractured rock mass and the influence of grout on the fracture network, and to achieve more realistic grouting numerical simulation, in this paper a grouting process simulation approach considering fluid–structure interaction is developed based on the 3D fractured network model. Firstly, the relationship between fracture apertures and trace lengths is used to obtain a more realistic value of fracture aperture; then a more reliable model is established; subsequently, based on the 3D fracture network model, different numerical models are established to calculate fluid dynamics (grout) and structure deformation (fractured rock mass), and the results are exchanged at the fluid–structure interface to realize the grouting process simulation using two-way fluid-structure interaction method. Finally, the approach is applied to analyze the grouting performance of a hydropower station X, and the results show that the grouting simulation considering fluid–structure interaction are more realistic and can simultaneously reveal the diffusion of grout and the deformation of fracture, which indicates that it is necessary to consider the effect of fluid–structure interaction in grouting simulation. The results can provide more valuable information for grouting construction.

The numerical simulation of rock mass grouting: a literature review

“…Wang et al (2017) based on the 3D DEM, conducted a sensitivity analysis of the grouting parameters in a single-fracture grouting numerical simulation considering the fluid–solid interaction and pointed out that the greater the grouting pressure, the more significant the impact of fluid-solid interaction. Based on this sensitivity analysis, Zhu et al (2019) proposed a simulation method of rock mass grouting process considering fluid–solid coupling effect based on the 3D fracture network. They realized the two-way fluid–solid interaction simulation of the grouting process.…”

Research on Water Pressure Distribution Characteristics and Lining Safety Evaluation of Deep Shaft in Water-Rich, Large, Fractured Granite Stratum

“…Fracture network construction mainly uses the Monte Carlo method [18][19][20][21] or actual fracture acquisition data to generate fractures, as well as the related discrete software (such as DFN (FLAC), PFC, UDEC, 3DEC, etc. ), to build discrete fracture network models [22][23][24][25]; fractal geometric theory partitions different fracture distribution areas [26,27]. This method can establish practical fractured rock mass, according to the different fractures (size and direction) in different rock masses, and the simulation effect is good [28][29][30].…”

Numerical investigation of flow control technology for grouting and blocking of flowing water in karst conduits

“…employed the CFD model and conducted numerical simulation of the flowing characteristics of the cemented paste backfill slurry in conduits while taking hydration into consideration. Zhu et al 36 . established a CFD model of the multiphase fluid, for grouting slurry, and a finite element coupling model, for the structural element in fractured rock masses.…”