Intelligent prediction of slope stability based on visual exploratory data analysis of 77 in situ cases

The fractures of different sizes in rock masses are important for describing rock fragmentation. The distribution dispersion of fracture size influences the blockiness level of the rock masses. Based on a normal statistical distribution, the volume ratio of blocks to rock (B) was obtained to describe the blockiness level. For exploring the effect of the dispersion of fracture size on blockiness level and the representative elementary volume (REV) of rock masses, the laboratory model and numerical simulation were established, and the theory of statistics and the method of analytical solution were applied. In addition, 4,525 practical rock models were established to qualitatively reproduce the behavior of B with changing domain size. The results show that by comparing the degree of convergence, the REV of a rock mass is determined by the fracture size rather than the degree of fracture dispersion. The value of B increases with the distribution dispersion of fracture size, indicating a higher blockiness level. From the experimental analysis of coin tossing, when the number of trials exceeds 69, the random results are nearly stable. In this study, 100 calculations were performed. A formula to calculate the blockiness by considering the dispersion degrees of fracture size was obtained. Moreover, a positive linear correlation between B and the coefficient of variation of fracture size was obtained. The rate of increase in B has a parabolic relationship with the ratio of fracture size to fracture spacing (L).

Section: Relationship Between the Distribution Dispersion Of Fracture...mentioning

confidence: 99%

“…The stability of rocks has always been a focus of concern. Wang et al estimated the effect of five indexes on the stability of slop by numerical and statistical methods (Wang et al, 2022c).…”

Section: Introductionmentioning

confidence: 99%

The influence of normal distribution dispersion of fracture size on blockiness and REV of fractured rock masses

Xia²

2023

“…In general, debris flows with small initial volumes can rapidly increase by several or even tens of orders of magnitude in volume through source erosion and entrainment processes (Shang et al, 2003;Wang et al, 2003;Zaginaev et al, 2019;Wang et al, 2022). Source erosion and entrainment processes significantly increase the debris flow volume and impact, which should be considered in the dynamic model (Chen et al, 2006;Wang et al, 2020;Guo et al, 2022;Wang et al, 2022;Wang et al, 2023).…”

Section: Introductionmentioning

confidence: 99%

Dynamics of debris flow-induced impacting onto rigid barrier with material source erosion-entrainment process

Fang²,

Li³

et al. 2023

The dynamics of debris flow impact considering the material source erosion-entrainment process is analyzed using a coupled SPH-DEM-FEM method. A complex coupled dynamic model of a debris flow, the erodible material source, and a rigid barrier is established in this paper. The applicability of the coupled SPH-DEM-FEM method for calculating the impact force of debris flow on the rigid barrier is verified by comparing the model with the laboratory test. The strain softening model is used to simulate the process from solid state to transition state and finally to liquid state of erodible material source. The impact force caused by debris flow considering the source erosion-entrainment process and the dynamic response of a rigid barrier is also analyzed. The results show that the volume of debris fluid, impact force, and dynamic response of a rigid barrier considering source erosion–entrainment are significantly greater than those of the original model. According to the calculation results, the existing formula for the impact force of a debris flow is then modified. The coupled numerical analysis method and the calculated results help to clarify the influence of erosion-entrainment, modify the calculation of the impact force of debris flow, and optimize the design of the rigid barrier.

“…In recent years, the number of ultrafine tailings reservoirs have been increasing gradually (Li et al, 2019;Shi et al, 2020;Han et al, 2022). However, the research efforts on ultrafine tailings particles are still inadequate, thereby inconducive to future sustainable development (Jing et al, 2019;Jing et al, 2021;Liu et al, 2021;Wang et al, 2022). The physical and chemical properties and engineering characteristics of slag show that slag exhibits aggregate properties.…”

Section: Introductionmentioning

confidence: 99%

Multiscale mechanical characterizations of ultrafine tailings mixed with incineration slag

Jing

Jia³

et al. 2023

Adding a type of municipal solid waste (incinerator slag) into ultrafine tailings can effectively enhance the mechanical properties of tailings. With an aim to study the macro- and micro-mechanical properties of the tailings slag mixture (TSM), the strength parameters (internal friction angle, cohesion) and micro-mechanical properties with different slag contents were analyzed by geotechnical experiments and particle flow simulations, respectively. The macroscale experimental results demonstrated that the strength parameters of TSM were much higher than that of tailings. Strength parameters also showed non-linear-rising trends with increasing slag content. For the slag content of 40%, the maximum cohesiveness of TSM was determined at 65.2 kPa, and the corresponding friction angle was 39.9°C. Furthermore, the Particle Flow Code (PFC) micro-simulation software was used to analyze the micro-mechanical characteristics of the TSM at different slag contents. The microscale simulation outcomes indicated that the particle transport, particularly in their moving directions, became increasingly chaotic with an increase in the slag content; also, the slag particles significantly impacted the shear processing zone of the TSM. These experimental and numerical results brought more scientific insights into the shear failure mechanism of TSM.