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Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid Ahmed Tadjer Abdelhakim Idir Kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of civil and Environmental engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary research center for construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

Initial excess pore water pressures induced by tunnelling in soft ground

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Journal of Central South University 2015年第11期22卷 4300-4309页

作者：梁荣柱夏唐代林存刚俞峰吴世明 College of civil engineering and Architecture Zhejiang University research center of Coastal and Urban Geotechnical engineering Zhejiang University College of civil Construction and Environmental Engineering Ningbo University School of civil engineering and Architecture Zhejiang Sci-Tech University Insigma Group Co. Ltd.

Tunnelling-induced long-term consolidation settlement attracts a great interest of engineering practice. The distribution and magnitude of tunnelling-induced initial excess pore water pressure have significant effects on the long-term consolidation settlement. A simple and reliable method for predicting the tunnel-induced initial excess pore water pressure calculation in soft clay is proposed. This method is based on the theory of elasticity and SKEMPTON's excess pore water pressure theory. Compared with the previously published field measurements and the finite-element modelling results, it is found that the suggested initial excess pore water pressure theory is in a good agreement with the measurements and the FE results. A series of parametric analyses are also carried out to investigate the influences of different factors on the distribution and magnitude of the initial excess pore water pressure in soft ground.

关键词： initial excess pore water pressure geostress relie

Fault Identification for Shear-Type Structures Using Low-Frequency Vibration Modes

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Computer Modeling in engineering & Sciences 2024年第3期138卷 2769-2791页

作者： Cuihong Li Qiuwei Yang Xi Peng School of civil engineering Shaoxing UniversityShaoxing312000China School of civil and Transportation engineering Ningbo University of TechnologyNingbo315211China engineering research center of industrial construction in civil engineering of zhejiang Ningbo University of TechnologyNingbo315211China

Shear-type structures are common structural forms in industrial and civil buildings,such as concrete and steel frame *** diagnosis of shear-type structures is an important topic to ensure the normal use of *** main drawback of existing damage assessment methods is that they require accurate structural finite element models for damage ***,for many shear-type structures,it is difficult to obtain accurate *** order to avoid finite elementmodeling,amodel-freemethod for diagnosing shear structure defects is developed in this *** method only needs to measure a few low-order vibration modes of the *** proposed defect diagnosis method is divided into two *** the first stage,the location of defects in the structure is determined based on the difference between the virtual displacements derived from the dynamic flexibility matrices before and after *** the second stage,damage severity is evaluated based on an improved frequency sensitivity *** innovations of this method lie in two *** first innovation is the development of a virtual displacement difference method for determining the location of damage in the shear *** second is to improve the existing frequency sensitivity equation to calculate the damage degree without constructing the finite *** has been verified on a numerical example of a 22-story shear frame structure and an experimental example of a three-story steel shear *** on numerical analysis and experimental data validation,it is shown that this method only needs to use the low-order modes of structural vibration to diagnose the defect location and damage degree,and does not require finite element *** proposed method should be a very simple and practical defect diagnosis technique in engineering practice.

关键词： Fault diagnosis shear steel structure vibration mode dynamic flexibility frequency sensitivity

Experimental Investigation of Wave-Current Loads on a Bridge Shuttle-Shaped Cap–Pile Foundation

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1565-1592页

作者： Chenkai Hong Zhongda Lyu Fei Wang Zhuo Zhao Lei Wang College of Science and Technology Ningbo UniversityNingbo315300China engineering research center of industrial construction in civil engineering of zhejiang Province Ningbo University of TechnologyNingbo315211China

To scrutinize the characteristics of wave-current loads on a bridge shuttle-shaped cap–pile foundation,a 1:125 test model was considered in a laboratory *** inline,transverse and vertical wave–current forces acting on the shuttle-shaped cap-pile group model were measured considering both random waves and a combination of random waves with a *** experimental results have shown that the wave-current forces can be well correlated with the wave height,the wavelength,the current velocity,the incident direction and the water level in the marine *** increase in the current velocity can lead to a sharp increase in the inline and transverse wave-current forces,while the vertical wave-current force ***,the wave-current forces are particularly strong when a combination of high tide,strong wave and strong current is considered.

关键词： Shuttle-shaped cap-pile foundation wave-current force wave flume experiment sea-crossing bridge

Numerical Analysis of the Hydrodynamic Behavior of a Remotely Operated Vehicle in Multi-Directional Flow

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Fluid Dynamics & Materials Processing 2023年第9期19卷 2361-2384页

作者： Hongfei Cao Zhongda Lyu Xi Peng Zhuo Zhao Faculty of Mechanical engineering and Mechanics Ningbo UniversityNingbo315211China School of civil and Transportation engineering Ningbo University of TechnologyNingbo315211China engineering research center of industrial construction in civil engineering of zhejiang Ningbo University of TechnologyNingbo315211China

In recent years,Remotely Operated Vehicles(ROVs)have played an increasingly important role in the construc-tion and monitoring of underwater pile ***,due to the open frame structure of such vehicles,a gap of knowledge still exists with regard to their hydrodynamic *** this study,the hydrodynamic stability of such vehicles is investigated numerically by means of a multiple reference frame *** hydrodynamic characteristics of the ROV when it moves horizontally and upward in the vertical plane are *** is found that there is interference between the horizontal and vertical thrusters of the *** is also interference between the propeller thrust and drag(or lift).The effect of the vertical thrusters can increase the horizontal thrust by about 5%.The horizontal thrusters create a low-pressure area below the body,which can make vertical drag experienced by the ROV signiﬁcantly higher.

关键词： ROV propellers combined action vector layout ducted propeller CFD

Influence of adjacent shield tunneling construction on existing tunnel settlement: field monitoring and intelligent prediction

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Journal of zhejiang University-Science A(Applied Physics & engineering) 2023年第12期24卷 1106-1119页

作者： Long RAN Yang DING Qizhi CHEN Baoping ZOU Xiaowei YE School of civil engineering and Architecture Zhejiang University of Science&TechnologyHangzhou 310023China zhejiang engineering research center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou 310015China Department of civil engineering Zhejiang UniversityHangzhou 310058China

Urban subway tunnel construction inevitably disturbs the surrounding rock and causes the deformation of existing subway structures. Dynamic predictions of the tunnel horizontal displacement, tunnel ballast settlement, and tunnel differential settlement are important for ensuring the safety of buildings and tunnels. First, based on the Hangzhou Metro project, we analyzed the influence of construction on the deformation of existing subway structures and the difficulties and key points in monitoring. Then, a deformation prediction model, based on a back propagation(BP) neural network, was established with massive monitoring data. In particular, we analyzed the influence of four structures of the BP neural network on prediction performance, i.e., single input–single hidden layer–single output, multiple inputs–single hidden layer–single output, single input–double hidden layers–single output, and multiple inputs–double hidden layers–single output, and verified them using measured data.

关键词： Subway Horizontal displacement of tunnel Settlement of tunnel ballast Differential settlement of tunnel Deformation prediction Back propagation(BP)neural network

Centrifuge tests for seismic response of single pile foundation supported wind turbines in sand influenced by earthquake history

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Earthquake engineering and engineering Vibration 2023年第3期22卷 623-636页

作者： Wang Yubing Zhang Zhongchang Wu Xiaofeng Zhu Bin center for Hypergravity Experiment and Interdisciplinary research College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China Hangzhou Urban construction&Investment Group Co. Ltd.Hangzhou 310005China MOE Key Laboratory of Soft Soils and Geoenvironmental engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China

This paper reports on two sets of centrifuge model tests of wind turbines in dry sand and saturated sand subjected to earthquake *** wind turbine system is composed of a single pile foundation and a wind *** tests were applied with liquefaction experiments and analysis projects(LEAP)waves to simplify the *** objectives of the tests are to investigate:(1)the influence of earthquake history on the seismic response of wind turbines;(2)the influence of earthquake history on the dynamic pile-soil interaction;and(3)the influence of two different foundation types on the seismic response of wind *** tests indicated that earthquake history has a significant influence on the natural frequency of the pile and the soil around the pile in the saturated sand,but has no obvious influence on the dry *** shear modulus of the soil and the acceleration amplification factor of the pile top in both tests increased and the maximum bending moment envelope of the single pile foundation *** stiffness of the p-y curve in saturated sand was increased by the earthquake history,while that in dry sand was not significantly affected.

关键词： earthquake history effect wind turbine pile bending moment dry and saturated sand ground dynamic p-y curves

Mechanical performances of shield tunnel segments under asymmetric unloading induced by pit excavation

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Journal of Rock Mechanics and Geotechnical engineering 2023年第6期15卷 1547-1564页

作者： Gang Wei Feifan Feng Chengbao Hu Jiaxuan Zhu Xiao Wang Department of civil engineering Hangzhou City UniversityHangzhou310015China Key Laboratory of Safe construction and Intelligent Maintenance for Urban Shield Tunnels of zhejiang Province Hangzhou310015China zhejiang engineering research center of Intelligent Urban Infrastructure Hangzhou310015China College of civil engineering and Architecture Zhejiang UniversityHangzhou310058China

To explore the stress and deformation responses,as well as the failure characteristics of the shield tunnel segment of Hangzhou Metro under the influences of pit excavation and other surrounding projects,a self-developed“shield tunnel segment hydraulic loading system”was used to carry out full-scale loading tests on the three-ring staggered assembled *** structural performances and failure process of the tunnel segment under step-by-step asymmetric unloading were studied.A safety index was proposed to describe the bearing capacity of the ***,a finite element model(FEM)was established to analyze the bearing capacity of segment using the test ***,the effect of reinforcement with a steel plate on the deformation and bearing capacity of the segment was *** results showed that under asymmetric unloading,the peak value and amplitude of the bending moment on the near unloading side converged with a greater value than those on the far *** concrete internal force exhibited a directional transformation at different load *** first appeared at the 180inner arc surface of the bottom standard block and then expanded to both sides,while the rate of crack propagation of the outer arc surface was relatively *** bearing capacity of the segments can be evaluated by the combination of the factors,*** residual bearing capacity coefficient,moment transfer coefficient,and characterization *** segments approaching failure can facilitate the increase in the residual bearing capacity coefficient by more than 50%.This can provide guidance for the service assessment of metro tunnel operations.

关键词： Shield tunnel segment Full-scale test Asymmetric unloading Stress and deformation Safety index

Comparison study of phosphorus adsorption on different waste solids:Fly ash,red mud and ferric–alum water treatment residues

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Journal of Environmental Sciences 2016年第12期28卷 79-86页

作者： Ying Wang Yange Yu Haiyan Li Chanchan Shen School of Environment Beijing Normal University Beijing engineering research center of Sustainable Urban Sewage System construction and Risk Control Beijing University of Civil Engineering and Architecture

The adsorption of phosphorus （P） onto three industrial solid wastes （fiy ash, red mud and ferric-alum water treatment residual （FAR）） and their modified materials was studied systematically ufa batch experiments. Compared with two natural adsorbents （zeolite and diatomite）, three solid wastes possessed a higher adsorption capacity for P because of the higher Fe, A1 and Ca contents. After modification （i.e., the fly ash and red mud modified by FeC13 and FARs modified by HC1）, the adsorption capacity increased, especially for the modified red mud, where more Fe bonded P was observed. The P adsorption kinetics can be satisfactorily fitted using the pseudo-second-order model. The Langmuir model can describe well the P adsorption on all of the samples in our study, pH and dissolved organic matter （DOM） are two important factors for P adsorption. Under neutral conditions, the maximum adsorption amount on the modified materials was observed. With the deviation from pH 7, the adsorption amount decreased, which resulted from the change of P species in water and surface charges of the adsorbents. The DOM in water can promote P adsorption, which may be due to the promotion effects of humic-Fe（A1） complexes and the pH buffer function exceeds the depression of competitive adsorption.

关键词： Phosphorus Adsorption Solid wastes DOM