Kai Wang¹, Biao He^2,*, Pijush Samui³, Jian Zhou⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 229-253, 2024, DOI:10.32604/cmes.2024.047569

Abstract Rock bursts represent a formidable challenge in underground engineering, posing substantial risks to both infrastructure and human safety. These sudden and violent failures of rock masses are characterized by the rapid release of accumulated stress within the rock, leading to severe seismic events and structural damage. Therefore, the development of reliable prediction models for rock bursts is paramount to mitigating these hazards. This study aims to propose a tree-based model—a Light Gradient Boosting Machine (LightGBM)—to predict the intensity of rock bursts in underground engineering. 322 actual rock burst cases are collected to constitute an exhaustive rock burst dataset, which serves… More >

Junjie Zhao, Diyuan Li^*, Jingtai Jiang, Pingkuang Luo

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 275-304, 2024, DOI:10.32604/cmes.2024.046960

Abstract Traditional laboratory tests for measuring rock uniaxial compressive strength (UCS) are tedious and time-consuming. There is a pressing need for more effective methods to determine rock UCS, especially in deep mining environments under high in-situ stress. Thus, this study aims to develop an advanced model for predicting the UCS of rock material in deep mining environments by combining three boosting-based machine learning methods with four optimization algorithms. For this purpose, the Lead-Zinc mine in Southwest China is considered as the case study. Rock density, P-wave velocity, and point load strength index are used as input variables, and UCS is regarded… More > Graphic Abstract

Wei Chen^*, Wuwen Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 859-872, 2024, DOI:10.32604/fdmp.2023.029310

Abstract River sand is an essential component used as a fine aggregate in mortar and concrete. Due to unrestrained exploitation, river sand resources are gradually being exhausted. This requires alternative solutions. This study deals with the properties of cement mortar containing different levels of manufactured sand (MS) based on quartzite, used to replace river sand. The river sand was replaced at 20%, 40%, 60% and 80% with MS (by weight or volume). The mechanical properties, transfer properties, and microstructure were examined and compared to a control group to study the impact of the replacement level. The results indicate that the compressive… More >

Yifan Huang¹, Zikang Zhou^1,2, Mingyu Li¹, Xuedong Luo^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 3147-3165, 2024, DOI:10.32604/cmes.2024.045947

Abstract Accurately estimating blasting vibration during rock blasting is the foundation of blasting vibration management. In this study, Tuna Swarm Optimization (TSO), Whale Optimization Algorithm (WOA), and Cuckoo Search (CS) were used to optimize two hyperparameters in support vector regression (SVR). Based on these methods, three hybrid models to predict peak particle velocity (PPV) for bench blasting were developed. Eighty-eight samples were collected to establish the PPV database, eight initial blasting parameters were chosen as input parameters for the prediction model, and the PPV was the output parameter. As predictive performance evaluation indicators, the coefficient of determination (R²), root mean square… More >

Shijun Zhao¹, Qing Zhang², Yusong Miao¹, Weizhao Zhang³, Xinbo Zhao¹, Wei Xu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 3167-3187, 2024, DOI:10.32604/cmes.2023.045015

Abstract The surrounding rock of roadways exhibits intricate characteristics of discontinuity and heterogeneity. To address these complexities, this study employs non-local Peridynamics (PD) theory and reconstructs the kernel function to represent accurately the spatial decline of long-range force. Additionally, modifications to the traditional bond-based PD model are made. By considering the micro-structure of coal-rock materials within a uniform discrete model, heterogeneity characterized by bond random pre-breaking is introduced. This approach facilitates the proposal of a novel model capable of handling the random distribution characteristics of material heterogeneity, rendering the PD model suitable for analyzing the deformation and failure of heterogeneous layered… More >

Shuyu Wang¹, Linjuan Wang^1,*, Yunteng Wang²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.3, pp. 1-1, 2023, DOI:10.32604/icces.2023.09217

Abstract Material heterogeneity plays an important role in the blasting induced rock fracture. However, the investigation of the effects of material heterogeneity is limited by the numerical methods for dynamic fracture. In the work, we propose a peridynamic model for brittle rock with heterogeneous micro-modulus and critical stretch to investigate the effects of material heterogeneity on the blast-induced rock crack initiation and propagation. The discretization in polar coordinates is introduced into the proposed model to avoid the fallacious directional guidance to the crack initiation around the hole. The proposed model satisfies the More >

Hao Zhang¹, Yan Zhang^1,*, Wei Liu², Ximin Zhang³, Xiang Liu²

Energy Engineering, Vol.121, No.1, pp. 27-42, 2024, DOI:10.32604/ee.2023.041410

Abstract The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale, which affects the fracturing effect. Accordingly, we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation, based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical simulation. The results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid immersion. And a 15% concentration of hydrochloric acid can effectively dissolve shale. Furthermore, the… More >

Duan Zhu^1,2, Zhende Zhu^1,2, Cong Zhang^1,2,*, Lun Dai^1,2, Baotian Wang^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.3, pp. 2445-2470, 2024, DOI:10.32604/cmes.2023.030847

Abstract Tunnel construction is susceptible to accidents such as loosening, deformation, collapse, and water inrush, especially under complex geological conditions like dense fault areas. These accidents can cause instability and damage to the tunnel. As a result, it is essential to conduct research on tunnel construction and grouting reinforcement technology in fault fracture zones to address these issues and ensure the safety of tunnel excavation projects. This study utilized the Xianglushan cross-fault tunnel to conduct a comprehensive analysis on the construction, support, and reinforcement of a tunnel crossing a fault fracture zone using the three-dimensional finite element numerical method. The study… More >

Lei Zhu^1,2, Bin Liu², Xuewei Liu^2,*, Wei Deng¹, Wenjie Yao¹, Ying Fan¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.2, pp. 401-427, 2024, DOI:10.32604/fdmp.2023.041444

Abstract To analyze the effects of a time-varying viscosity on the penetration length of grouting, in this study cement slurries with varying water-cement ratios have been investigated using the Bingham’s fluid flow equation and a discrete element method. A fluid-solid coupling numerical model has been introduced accordingly, and its accuracy has been validated through comparison of theoretical and numerical solutions. For different fracture forms (a single fracture, a branch fracture, and a fracture network), the influence of the time-varying viscosity on the slurry length range has been investigated, considering the change in the fracture aperture. The results show that under different… More >

Jonathan T. Wolkinson, Michael Weinberg^*

International Journal of Mental Health Promotion, Vol.25, No.10, pp. 1137-1145, 2023, DOI:10.32604/ijmhp.2023.029641

Abstract Living under ongoing shelling and missile attacks could cause a widespread of disruption of everyday life and emotional distress. Coping with such distress could be associated with the personal resources of religion and spirituality. The present study aimed to examine the relationships between religiosity and spirituality with Post Traumatic stress Disorder (PTSD) symptoms among a civilian population frequently exposed to missile and rocket threats. One hundred and twenty-four (N = 124) civilian participants living within 10 km from shelling and missile attacks fired towards them, completed demographic, religiosity, spirituality, and PTSD questionnaires. The study findings demonstrate that religiosity is associated… More >