The Use of Hoek Brown Failure Criterion on Determination of the Geo-Mechanical Parameters of a Grouting Consolidation Body

Abstract

In this paper, the mechanical parameters of the grouting consolidation body on the rock block are studied using the Acoustic velocity test case and the revised Hoek-Brown failure criterion in underground metal mines. In light of the hidden resources in the collapsed area of the underground metal mine, the intact rock drilling core cannot be obtained to perform the mechanical test because of extreme damage or because it is completely broken. Therefore, pure cement grouting is used to reinforce the extremely broken rock mass within the collapsed area of the hidden resources. The RQD value and water permeability are tested to indicate that cement pastes can fill the cracks in broken rock blocks and can improve the integrity of the broken rock mass. To detect the grouting consolidation effect of the fractured rock mass and evaluate the mechanical parameters of the consolidation body, a nondestructive test is applied to measure the Acoustic velocity of the consolidation body after grouting. Initially, the measured Acoustic velocity is adopted to calculate the damage index (or integrity index), which is approximately equivalent to the disturbance factor. Then, the modified Hoek-Brown failure criterion is used to evaluate the mechanical parameters of the grouting consolidation body. Finally, to verify this method, the mechanical parameters of the rock mass are also obtained by a laboratory test. The outcomes show that the current research can serve as a practical method when evaluating rock mass quality by the grouting treatment.INDEX TERMS Acoustic waves, civil engineering, consolidation body, Hoek Brown criteria, Young's modulus.

A Two-Dimensional Planar Fracture Network Model for Broken Rock Mass Based on Packer Test and Fractal Dimension

“…Engineering Background. A specific range of sliding fracture zones was exposed in an underground mine of the Fankou Lead-Zinc Mine due to collapse [24]. Fankou Lead-Zinc Mine is an underground mine located in Shaoguan City, Guangdong Province, China.…”

“…Because of poor geological conditions, the mine adopts the room and pillar method to mine lead-zinc ore at intervals through blasting. The engineering background in detail was stated by Wen et al's research [24]. Due to unreasonable excavation sequence and untimely filling, as a result, the filling body on both sides of 0# stope slides to the 0# goaf and the roof of the 0# stope collapses.…”

“…Moreover, experimental analyses and numerical simulations of the grouting reinforcement for broken rock masses have been presented by some researchers [20][21][22][23][24]. Lange and Van Geel [25] constructed a new experimental model to analyze and evaluate the effectiveness of the fluid pressure gradient and mass flux in a surrounding rock mass with two fractures.…”

The Disturbance Factor of Hoek–Brown Failure Criterion in Dam Foundations

“…Researchers have tried to establish quanti cation methods for the D. For this purpose, Luo and Fu (2012) proposed relationships between the D and the P-wave velocity of rock masses using the elastic damage theory. Wen et al (2019) measured the acoustic velocity of the rock mass to calculate the equivalent disturbance effect. Also, Yang et al (2020) used the acoustic P-wave velocity to quantify the D by statistically analyzing a large amount of in-situ test data measured on rock slopes.…”

An Experimental Investigation on the Shear-Seepage Coupling Failure Behavior of Split Grouting-Reinforced Body

“…Recently, researchers have attached importance to research on the physical and mechanical properties of grouting-reinforced bodies, achieving certain results [13][14][15]. Liu et al [16] investigated the mechanical properties of a sand-filled GRB under different seepage pressures.…”