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International Journal of Mining Science and Technology 2024年第5期34卷 713-729页

作者： Shili Qiu Shirui zhang Quan Jiang Shaojun li Hao zhang Qiankuan Wang state key laboratory of geomechanics and geotechnical engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China state key laboratory of Ocean engineering Shanghai Jiao Tong UniversityShanghai 200240China

The Voronoi grain-based breakable block model(VGBBM)based on the combined finite-discrete element method(FDEM)was proposed to explicitly characterize the failure mechanism and predict the deformation behavior of hard-rock mine *** influence of the microscopic parameters on the macroscopic mechanical behavior was investigated using laboratory-scale *** field-scale pillar models(width-to-height,W/H=1,2 and 3)were calibrated based on the empirically predicted stress-strain curves of Creighton mine *** results indicated that as the W/H ratios increased,the VGBBM effectively predicted the transition from strain-softening to pseudo-ductile behavior in pillars,and explicitly captured the separated rock slabs and the V-shaped damage zones on both sides of pillars and conjugate shear bands in core zones of *** volumetric strain field revealed significant compressional deformation in core zones of *** the peak strains of W/H=1 and 2 pillars were relatively consistent,there were significant differences in the strain energy storage and release mechanism.W/H was the primary factor influencing the deformation and strain energy in the pillar *** friction coefficient of the structural plane was also an important factor affecting the pillar strength and the weakest discontinuity *** fracture surface was controlled by the discontinuity angle and the friction *** study demonstrated the capability of the VGBBM in predicting the strengths and deformation behavior of hard-rock pillars in deep mine design.

关键词： Pillar strength FDEM Voronoi tessellation Spalling Bulking

Crack initiation of granite under uniaxial compression tests:A comparison study

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Journal of Rock Mechanics and geotechnical engineering 2020年第3期12卷 656-666页

作者： G.K.zhang H.B.li M.y.Wang x.F.li state key laboratory of geomechanics and geotechnical engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China School of Mechanical engineering Nanjing University of Science and TechnologyNanjing210094China University of Chinese Academy of Sciences Beijing100049China

In this study,a combination of acoustic emission(AE)method(AEM)and wave transmission method(WTM)is used to investigate the behaviors of AE and ultrasonic properties corresponding to initial fracturing in granitic *** relationships of AE characteristics,frequency spectra,and spatial locations with crack initiation(CI)are *** anisotropic ultrasonic characteristics,velocity distributions in different ray paths,wave amplitudes,and spectral characters of transmitted waves are *** identify CI stress,damage initiations characterized by strain-based method(SBM),AEM and WTM are *** granite samples,it shows that the ratio of CI stress to peak strength estimated by SBM ranges from 0.4 to 0.55,and 0.49-0.6 by WTM,which are higher than that of AEM(0.38-0.46).The CI stress identified by AEM indicates the onset of microcracking,and the combination of AEM and WTM provides an insight into the detection of rock damage initiation and anisotropy.

关键词： Crack initiation(CI)stress Acoustic emission(AE) Ultrasonic transmission Wave velocity Granite

Vibration reduction effect of the shielding pile based on seismic wave attenuation in shallow underground spaces

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Journal of Earth Science 2024年

作者： Qiankuan Wang Shili Qiu Aiguo xing xueyong xu ye Zhou yao Cheng Haoshan zhang Bo Wu yiwei liu Mingzhe zhang yu Zhuang state key laboratory of Ocean engineering， Shanghai jiao Tong University state key laboratory of geomechanics and geotechnical engineering， Institute of Rock and Soil Mechanics， Chinese Academy of Sciences North Information Control Research Academy Group CO.， lTD Faculty of engineering， China University of Geosciences

Seismic hazards threaten underground structures and subsequently affect surface buildings， making effective vibration reduction measures crucial in shallow underground spaces. This paper proposes a multi-layer shielding pile based on the seismic wave attenuation theory of refraction dispersion and diffraction loss as a new vibration reduction method. By using the dynamic wave interaction between the unique multi-layer structure of the shielding pile and the seismic wave， a shielding area with significant attenuation of the ground motion is formed to achieve the purpose of vibration reduction. The spectral element method (SEM) with high-order source time function and convolution perfect matching layer (PMl) is used to simulate the numerical models of shielding piles with different parameters (including background models and excavation models)， and the characteristics of ground motion and site effect near shielding piles in various models are analyzed. The study reveals the control effect and regulation of the material， size， and shape of the shielding pile on its vibration reduction effect， and determines the shielding pile parameters with the best vibration reduction effect. Shielding piles enriches the vibration reduction measures for structures in shallow underground spaces， and provides a new method for preventing seismic hazards under dynamic load.

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REGRESSION ANAlySIS OF IN-SITU STRESS FIElD IN UNDERGROUND POWERHOUSE AREA OF ONE HyDROPOWER STATION

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REGRESSION ANALYSIS OF IN-SITU STRESS FIELD IN UNDERGROUND P...

The 7th International Symposium on Rockburst and Seismicity in Mines(RaSiM7)

作者： WEN-DONG yANG QIANG-yONG zhang xIU-yONG yU GANG WANG and yUAN lI geotechnical and Structural engineering Research Center Shandong University Jinan 250061 P.R.China

＜正＞Based on the measured data of in-situ stress and engineering geological conditions,three-dimensional regression calculating model of the in-situ stress in an underground powerhouse zone is *** takes into account the actual stratigraphic distribution as well as the *** optimal regression coefficient of in-situ stress is obtained through multiple regression method and three-dimensional numerical *** initial in-situ stress in underground powerhouse zone is regressed *** calculated result shows the magnitude and orientation of the principle stress obtained from regression analysis is closed to the measured *** provides a rational three-dimensional initial in-situ stress field for excavating simulation and analysis of long-term stability of the underground ***,the orientation of maximum principal stress parallels to the powerhouse *** result also validates that the design is rational in underground zone of the hydropower station.

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基于证据理论的隧道挤压变形预测

应用基础与工程科学学报 2021年第5期29卷 1156-1170页

作者：焦玉勇欧光照王浩张国华邹俊鹏谭飞张为社中国地质大学(武汉)工程学院湖北武汉430074 中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071

准确预测或识别隧道挤压变形对于隧道的设计和施工非常重要.基于案例统计和证据理论,建立了一种新的隧道挤压变形等级预测方法.首先综合考虑隧道挤压变形影响因素,选取强度应力比、隧道埋深、隧道等效直径、支护刚度、岩体质量指标作为... 详细信息

准确预测或识别隧道挤压变形对于隧道的设计和施工非常重要.基于案例统计和证据理论,建立了一种新的隧道挤压变形等级预测方法.首先综合考虑隧道挤压变形影响因素,选取强度应力比、隧道埋深、隧道等效直径、支护刚度、岩体质量指标作为挤压变形预测评价指标.然后基于Hoek提出的隧道挤压变形分级方案,建立了隧道挤压变形等级的识别框架.基于挤压变形案例统计和分析,建立了各评价指标的高斯分布隶属度模型,客观地确定各指标的基本概率分配(BPA).最后通过D-S合成公式融合生成的BPA,实现对隧道挤压变形等级的预测.此外,采用准确率和Kappa系数作为模型准确率的评价指标,对国内外139组隧道挤压变形数据进行了验证,准确率和Kappa系数分别为82%和0.77.将该模型应用于木寨岭高速公路隧道的围岩挤压变形预测,预测结果与现场实际条件完全一致,进一步验证了本文模型的准确性和适用性.本文的研究结果有利于提高隧道挤压变形预测的理论水平和可靠性,为类似工程提供参考.

关键词：挤压变形预测预测指标案例统计证据理论高斯分布基本概率分配(BPA)

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隧道洞口滑坡稳定性分析与防治措施

岩土力学 2008年第S1期29卷 311-314页

作者：张伟焦玉勇郭小红中科科学院武汉岩土力学研究所岩土力学与工程国家重点实验室武汉430071 中交第二公路勘察设计研究院有限公司武汉430056

受工程地质条件、水文地质条件及人为因素等的影响,公路隧道洞口施工过程中易发生洞口滑坡。综合连霍国道主干线宝鸡天水高速公路码头隧道洞口滑坡的形成特点、工程地质及水文地质特征,采用非线性有限元法对该洞口滑坡进行了分析,探讨... 详细信息

受工程地质条件、水文地质条件及人为因素等的影响,公路隧道洞口施工过程中易发生洞口滑坡。综合连霍国道主干线宝鸡天水高速公路码头隧道洞口滑坡的形成特点、工程地质及水文地质特征,采用非线性有限元法对该洞口滑坡进行了分析,探讨了变形和塑性区分布特征,得到了滑面位置,提出了加固治理方案,为今后类似工程提供参考与借鉴。

关键词：洞口滑坡边坡稳定性分析有限元预应力锚索抗滑桩

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基于显式时间积分的球颗粒DDA计算方法

岩土力学 2019年第11期40卷 4515-4522页

作者：赵强焦玉勇张秀丽谢壁婷王龙黄刚海中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 中国科学院大学北京100049 中国地质大学(武汉)工程学院湖北武汉430074 国家电网山东省电力公司经济技术研究院山东济南250021 湖南科技大学土木工程学院湖南湘潭411201

非连续变形分析方法(DDA)是一种平行于有限元法的新型数值计算方法,该方法基于最小势能原理,把每个离散块体的变形、运动和块体之间的接触统一到平衡方程中进行隐式求解。然而,传统DDA方法在计算过程中需组装整体刚度矩阵并联立求解方程... 详细信息

非连续变形分析方法(DDA)是一种平行于有限元法的新型数值计算方法,该方法基于最小势能原理,把每个离散块体的变形、运动和块体之间的接触统一到平衡方程中进行隐式求解。然而,传统DDA方法在计算过程中需组装整体刚度矩阵并联立求解方程组,在用于大型岩土工程问题的三维数值模拟时占用内存较大、耗时较长、计算效率极低。因此,提出一种基于显式时间积分的三维球颗粒DDA方法。该方法在求解过程中不需要组装整体刚度矩阵,在求解加速度时,由于质量矩阵为对角矩阵,可存储为一维向量占用内存较少,且可分块逐自由度求解,效率较高,在接触判断上采用最大位移准则简化了接触算法,采用较小的时步,保证了计算的精确性;通过几个典型算例验证了该方法的准确性及计算效率。

关键词：非连续变形分析显式时间积分质量矩阵最大位移准则岩土工程

地质雷达检测防空洞注浆效果的技术方法及应用

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岩土力学 2008年第S1期29卷 307-310页

作者：吴火珍焦玉勇李海波张秀丽中国科学院武汉岩土力学研究所国家重点实验室武汉430071

结合电磁波在多种介质中的传播特征,对电磁波在岩土体介质中传播的各种影响因素进行分析,得到接收天线接收到的波形图。从地质雷达对某人防洞注浆效果检测应用可以看出,通过计算机显示的波形图能够直观、清晰的检测不密实或者空洞区域,... 详细信息

结合电磁波在多种介质中的传播特征,对电磁波在岩土体介质中传播的各种影响因素进行分析,得到接收天线接收到的波形图。从地质雷达对某人防洞注浆效果检测应用可以看出,通过计算机显示的波形图能够直观、清晰的检测不密实或者空洞区域,并取得较好的应用效果。但地质雷达是是一种正在不断发展的探测技术,如何正确处理探测过程中的各种问题,得到准确的检测结果,需要积累大量的实践经验。

关键词：地质雷达波形图检测注浆效果

Construction of an ultra-deep diaphragm wall:a case study

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Journal of Chongqing University 2018年第1期17卷 1-16页

作者： SUN Jie zhang Zi-xin HUANG xin JU xin Department of geotechnical engineering Tongji Univers#y Shanghai 200092 P. R. China Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji University Shanghai 200092 P. R. China

This paper presents a case study on an ultra-deep diaphragm wall with a depth of 110 m constructed in Ningbo City. The in-situ application shows that using Bauer BC40 cutter machine in conjunction with cutter wheels specified for different strata would be qualified for constructing the 110 m diaphragm wall with high efficiency and precision given that the quality of slurry and poured concrete can be guaranteed. The ground settlement can be effectively controlled by using the overlapping construction method. Sliding failure as a whole characterized by pronounced lateral deformation is likely to occur in the upper muddy clay layer due to its high compressibility and sensitivity. In contrast, local collapse of trench walls tends to happen in the sandy silt strata. Furthermore, careful attention should be paid to sandy silt during the entire construction period as the vertical displacement of the sandy silt continues to develop even atter concrete pouring.

关键词： diaphragm wall soft soil quality control settlement overlapping method trench cutter BC40