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Journal of Rock Mechanics and Geotechnical Engineering 2022年第2期14卷 663-669页

作者： Yue Qin Qiankun Wang Dongsheng Xu Jiaming Yan Shanshan Zhang School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan430070China

A novel fiber Bragg grating(FBG)sensor with three-dimensional(3D)fused deposition modeling(FDM)approach is proposed for effective stress measurement in soil *** three-diaphragm structure design is developed to measure earth and water pressures *** proposed transducer has advantages of small size,high sensitivity,low cost,immunity to electromagnetic interference and rapid *** working principle,design parameters,and manufacturing details are *** proposed transducer was calibrated for earth and water pressures measurement by using weights and a specially designed pressure chamber,*** calibration results showed that the wavelength of the transducer was proportional to the applied *** sensitivity coefficients of the earth and water pressures were 12.633 nm/MPa and 6.282 nm/MPa,*** tests and error analysis demonstrated the excellent stability and accuracy of the earth and water pressure *** performance of the proposed transducer was further verified by a model experimental test and numerical analysis,which indicated that the proposed transducer has great potential for practical applications.

关键词： Fused deposition modeling(FDM) Fiber bragg-grating(FBG)sensor Earth pressure water pressure

Influence of permeability anisotropy of seepage flow on the tunnel face stability

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Underground Space 2023年第1期8卷 1-14页

作者： Qiguang Di Pengfei Li Mingju Zhang Jie Wu Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China

This paper focuses on the influence of permeability anisotropy of seepage flow on the face stability for a shied *** analytical model has been proposed to present the hydraulic head distribution around the tunnel face in the anisotropic ground,considering the difference of permeability coefficient in the horizontal direction and the vertical *** rationality of the proposed model is ver-ified by a series of numerical ***,an analytical model of face stability for a tunnel under the anisotropic seepage has been established based on the limit analysis upper bound *** of the analytical solutions and the numerical simulations are conducted,and the limit support pressure of the two methods is *** effect of permeability anisotropy and water pressure on the stability of the tunnel face is analyzed through the three-dimensional analytical *** of permeability has a significant impact on the stability of the tunnel face,and its impact gradually *** can also be found that the water pressure coefficient of the tunnel face has a significant effect on the limit support pressure and the failure area when the ratio of the horizontal permeability to the vertical permeability is large.

关键词： Seepage flow Hydraulic head distribution Permeability anisotropy Shield tunnel water pressure

Mechanical behavior of sandstone during post-peak cyclic loading and unloading under hydromechanical coupling

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矿业科学技术学报:英文版 2023年第8期33卷 927-947页

作者： Yanlin Zhao Jinhai Liu Chunshun Zhang Houquan Zhang Jian Liao Sitao Zhu Lianyang Zhang School of Resources Environment and Safety EngineeringHunan University of Science and TechnologyXiangtan 411201China School of Emergency Technology and Management North China Institute of Science and TechnologyBeijing 101601China School of Civil Engineering Wuhan UniversityWuhan 430072China State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou 221116China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Department of Civil and Architectural Engineering and Mechanics University of ArizonaTucsonAZ 85721USA

This paper investigates mechanical behaviours of sandstone during post-peak cyclic loading and unloading subjected to hydromechanical coupling effect, confirming the peak and residual strengths reduction laws of sandstone with water pressure, and revealing the influence of water pressure on the upper limit stress and deformation characteristics of sandstone during post-peak cyclic loading and *** the rock strength, the experimental study confirms that the peak strength σ_(p) and residual strength σ_(r) decrease as water pressure P increases. Especially, the normalized strength parameters σ_(p)/σ_(pk) and σ_(r)/σ_(re) was negatively and linearly correlated with the P/σ_(3). Moreover, the Hoek-Brown strength criterion can be applied to describe the relationship between effective peak strength and effective confining stress. During post-peak cyclic loading and unloading, both the upper limit stress σ_(p(i)) and crack damage threshold stress σ_(cd(i)) of each cycle tend to decrease with the increasing cycle number. A hysteresis loop exists among the loading and unloading stress–strain curves, indicating the unloading deformation modulus E_(unload) is larger than the loading deformation modulus E_(load). Based on experimental results,a post-peak strength prediction model related to water pressure and plastic shear strain is established.

关键词： Post-peak stage Cyclic loading and unloading Hydromechanical coupling Sandstone water pressure

Three-dimensional theoretical analysis of seepage field in front of shield tunnel face

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Underground Space 2022年第4期7卷 528-542页

作者： Qiguang Di Pengfei Li Mingju Zhang Caixia Guo Fan Wang Jie Wu Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China

To evaluate hydraulic head distribution in front of a shield tunnel in a saturated soil layer,theoretical analysis and numerical simulations are carried out in this *** on the partial differential equilibrium equation of seepage flow,a three-dimensional(3D)theoretical analytical model of the shield tunnel face and the seepage field in front of it is established using the eigenfunction and the Fourier series expansion methods,and the hydraulic head calculation formula is *** with engineering cases,the theoretical analysis results and the 3D numerical simulation results are compared and *** effect of the water pressure of the tunnel face on the hydraulic head distribution is also *** results of the proposed analytical solution are in agreement with those of the numerical simulation solutions;moreover,the proposed analytical solution requires less time to calculate the seepage hydraulic head than the numerical *** ratio of the initial water table to the diameter(D)of tunnel face has a more significant impact on the hydraulic head distribution at a position 0.5D above the tunnel *** the water pressure on the tunnel face is not considered,the values of the hydraulic head are significantly underestimated.

关键词： Seepage flow Hydraulic head distribution Shield tunnel Numerical simulation water pressure

The influence of low-permeability cap on capillary pressure during pumping in unconfined aquifer

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Journal of Hydrodynamics 2013年第6期25卷 867-870页

作者：黄辉钱家忠匡星星陈冰宇马雷吴亚楠 School of Resources and Environmental Engineering Hefei University of Technology Department of Earth Sciences The University of Hong Kong

The pumping test in an unconfined aquifer with and without a low-permeability soil was studied experimentally to reveal the influence of the negative air pressure （NP） caused by the upper layer on the water content （w）, the water pressure （Pw）, as well as on the capillary pressure （Pc）. The study demonstrates that the NP generated in the vadose zone during pumping in the capper aquifer has a significant influence on w, Pw and Pc The Pc obtained from the capped aquifer is smaller than that without the upper layer. After the NP reaches a peak, the influence of the NP on Pc. is gradually declined as the air inflows through the upper layer which makes the NP gradually return to zero. When the air pressure returns to the atmospheric pressure, Pc in the vadose zone is only correlated with Pw, the same as the case with no upper layer.

关键词： low-permeability soil water content water pressure capillary pressure vadose zone pumping test

A Test Model of water pressures within a Fault in Rock Slope

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Journal of China University of Geosciences 2001年第4期12卷 309-311页

作者： Yang Tong Wang Baoxue Hu Heng Civil and Environmental Engineering School, Beijing Institute of Technology , Beijing 100083 Civil and Environmental Engineering School Beijing Institute of Technology Beijing 100083

This paper introduces model test results of water pressure in a fault, which is located in a slope and 16 different conditions. The results show that the water pressures in fault can be expressed by a linear function, which is similar to the theoretical model suggested by Hoek. Factors affecting water pressures are water level in tension crack, dip angle of fault, the height of filling materials and thickness of fault zone in sequence.

关键词： rock slope water pressure model test.

固定海上平台遭受水下爆炸载荷的非线性动态响应

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Journal of Marine Science and Application 2022年第4期21卷 168-176页

作者： Seyed Shahab Emamzadeh Faculty of Civil Engineering Group Engineering DepartmentKharazimi UniversityTehranIran

In this paper,the dynamic response of a fixed offshore platform subjected to the underwater explosion(UNDEX)and probable events following it have been *** pressure load due to UNDEX in a specified depth has been applied with a model that considers the effect of blast bubble fluctuations into *** effect of water on the natural frequency and Fluid-Structure interaction has been modeled as equivalent added mass *** effect of explosion distance on platform response is *** this regard,three cases of near,medium,and far-distance explosions are *** a case study,a real fixed offshore jacket platform,installed in the Persian Gulf,has been *** the UNDEX pressure load is considered and other dynamic loads such as surface water waves and winds have been *** loads,live loads and hydrostatic pressure has been considered in the static case based on the design *** results indicated that in near-distance explosions,the UNDEX pressure load can locally damage parts of the platform that are located at the same level as that of explosive material and it can destabilize the *** the medium to far distance explosion,a very large base shear was applied to the platform because more elements were exposed to the UNDEX load compared to the near-distance ***,precautionary measures against UNDEX such as risk assessment according to design codes are *** a result of this,member strengthening against explosion may be required.

关键词： Dynamic response water pressure Underwater explosion Added mass Offshore platforms

Key Technology of Ground Grouting Treatment for Inclined Shaft under Condition of Super Thick water-Rich Loose Layer

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Open Journal of Geology 2022年第12期12卷 1120-1130页

作者： Yang Yang The First Exploration Team of Anhui Province Bureau of Coal Geological Huainan China

Shaft is one of the important links of mine production. In recent years, wellbore deviation has occurred many times in various regions of China, especially under the condition of thick water-rich loose layer, wellbore deviation has become an important factor that seriously affects the safety of mine production and miners’ life. Taking the serious deviation of shaft in Guotun Coal Mine in Shandong Province as an example, this paper analyzes the causes of wellbore deviation from the aspects of wellbore geological conditions and wellbore construction methods, and grouting treatment engineering carried out on the deviated shaft under the condition of mine production. Through on-site grouting construction, repair and treatment are remarkable, which provides reference for the subsequent surface grouting treatment engineering of wellbore deviation.

关键词： Wellbore Deviation water pressure Grouting pressure Relief

MECHANISM OF DYNAMIC INSTABILITY FOR RIVERSIDE SUBGRADE

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MECHANISM OF DYNAMIC INSTABILITY FOR RIVERSIDE SUBGRADE