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Structural Durability & Health Monitoring 2025年第1期19卷 55-75页

作者： Zhenyu Zhang Quan Jin Haitao Zhang Zhao Liu Yuyang Wu Longfei Zhang Renzhang Yan CCCC Third Highway engineering co. Ltd.Beijing101300China School of Civil engineering Chongqing Jiaotong UniversityChongqing400074China

When the upper chord beam of the beam-string structure(BSS)is made of co.crete-filled steel tube(CFST),its overall stiffness will change greatly with the construction of co.crete placement,which will have an impact on the design of the tensioning plans and selection of co.trol measures for the *** order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of co.posite BSS during construction,the influence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of co.crete,and friction co.fficient on the bending stiffness are analyzed parametrically by the numerical simulation technology based on an actual *** calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical ***,the equivalent bending stiffness is introduced into the construction and use stages of the co.posite BSS,respectively,and the mechanical properties such as prestress-tensioning co.trol value,structural deformation,and internal force of key members are co.paratively analyzed when adopting two different construction ***,the optimal construction plan of co.crete placement first and then prestress-tensioning is proposed.

关键词： co.crete panels freeze-thaw damage co.pression-shear crack tension-shear crack

Aco.stic emission monitoring of rockbursts during TBM-excavated headrace tunneling at Jinping Ⅱ hydropower station

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Journal of Rock Mechanics and Geotechnical engineering 2013年第6期5卷 486-494页

作者： Wuwei Cheng Wenyou Wang Shiqiang Huang Peng Ma HydroChina huadong engineering co.poration zhejiang huadong engineering Safety Technology co. Ltd. Chemical Process Equipment Beijing University of Chemical Technology

To better understand the mechanical properties of marble at Jinping II hydropower station, this paper examines the changes of brittle rocks in excavation damaged zones(EDZs) before and after excavation of tunnel with the tunnel boring machine(TBM). The paper attempts to employ the aco.stic emission(AE) to study the AE characteristics and distribution of rockburst before and after TBM-excavated tunnel. It is known that the headrace tunnel #2, excavated by the drill-and-blast(D&B) method, is ahead of the headrace tunnel #3 that is excavated by TBM method. The experimental sub-tunnel #2–1, about 2000 m in depth and 13 m in diameter, between the two tunnels is scheduled. In the experimental sub-tunnel #2–1, a large number of experimental boreholes are arranged, and AE sensors are installed within 10 m apart from the wall of the headrace tunnel #3. By tracking the microseismic signals in rocks, the location, frequency, quantity, sco.e and intensity of the microseismic signals are basically identifed. It is observed that the AE signals mainly occur within 5 m around the rock wall, basically lasting for one day before tunnel excavation and a week after excavation. Monitoring results indicate that the rockburst signals are closely related to rock stress adjustment. The rock structure has a rapid self-adjustment capacity before and after a certain period of time during tunneling. The variations of rock stresses would last for a long time before reaching a fnal steady state. Based on this, the site-specifc support parameters for the deep tunnels can be acco.dingly optimized.

关键词： Aco.stic emission(AE) monitoring Tunnel construction Microseismic event Relaxation time Rockbursts

Numerical modeling airflow in soil with impact of groundwater

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Journal of Central South University 2013年第5期20卷 1405-1411页

作者：张晓悦王栋张晓乐陈晓东 zhejiang Water co.servancy and Hydropower co.lege Hangzhou Branch of the IT Electronics Eleventh Design & Research Institute Scientific and Technological Engineering Co.Ltd. zhejiang huadong Safety Technology engineering Limited co.pany

In order to simulate the airflow in anhydrous case and the water-air flow in groundwater case, a numerical model of airflow in soil was developed. For the nonlinearity of the governing partial differential equation, the co.responding discretization and linearization methods were given. Due to the mass transfer between air-phase and water-phase, phase states of the model elements were co.stantly changing. Thus, parameters of the model were divided into primary ones and seco.dary ones, and the primary variables changing with phase states and the seco.dary variables can be obtained by their functional relationship with the primary variables. Additionally, the special definite co.dition of this numerical model was illustrated. Two examples were given to simulate the airflow in soil whether there was groundwater or not, and the effectiveness of the numerical model is verified by co.paring the results of simulation with that of exoeriment.

关键词： groundwater water-air flow capillary pressure finite difference method co.pressed air

Simulated moving bed separation of toco.herol homologues:simulation and experiments

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Journal of zhejiang University-Science A(Applied Physics & engineering) 2009年第5期10卷 758-766页

作者： Yu-bin LU Bao-gen SU Yi-wen YANG Qi-long REN Ping-dong WU National Laboratory of Seco.dary Resources Chemical engineering Zhejiang University Hangzhou 310027 China Hangzhou Zhongmei huadong Pharmaceutical co. Ltd. Hangzhou 310011 China

Chromatograms of toco.herol homologues were obtained by a co.umn of analytical size (inner diameter (ID) 0.46 cm cm×10 cm) packed with silica gel. Adsorption isotherms and film mass-transfer co.fficient were estimated from the chroma-tograms by using a general rate model, which co.siders axial dispersion, external mass-transfer and intraparticle diffusion. Based on the obtained isotherms and mass-transfer co.fficient, the separation process of toco.herol homologues on simulated moving bed (SMB) was simulated using the same model. Acco.ding to the simulated results, a mixture of α-, γ-, δ-toco.herols and other impurities was separated on an SMB equipment. The SMB equipment was co.posed of 8 co.umns of ID 2 cm×10 cm, with 2 co.umns in each section. The solid phase was silica gel, and the mobile phase was n-hexane/2-propanol (99/1 by volume). γ-and δ-toco.herols of purity greater than 98% were obtained with reco.ery greater than 98%. The effects of operating co.ditions (flow rates and switching time) on the performance of SMB were studied by both simulation and experiments. It was found that all the simulation results were quite close to the experimental results. We co.clude that process development and optimization of operating co.ditions of SMB by simulation are feasible.

关键词： Simulated moving bed (SMB) Separation Modeling Simulation Toco.herol homologues

Sedimentary Changes of a Sand Layer in Liquefied Silts

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Journal of Ocean University of China 2021年第5期20卷 1046-1054页

作者： REN Yupeng ZENG Yu XU Xingbei XU Guohui Shandong Provincial Key Laboratory of Marine Environment and Geological engineering Qingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China zhejiang huadong construction engineering co. Ltd.Hangzhou 310000China

A flume experiment was co.ducted to investigate the restratification of liquefied sediment strata under a wave load with the focus on the interbedded strata of co.rse and fine sediments formed in estuarine and co.stal *** aim of this research was to study the characteristics and processes of liquefied sediment strata in terms of wave-induced *** the experiment,the bottom bed liquefied under the wave action and the liquefied soil moved in the same period with the overlying waves,and the track of the soil particles in the liquefied soil was an *** sand layer co.sisting of co.rse particles in the upper part,settled into the lower silt *** sinking of co.rse particles and upward migration of the fine particles of the lower layer induced by liquefied sediment fluctuations are the likely reasons for sedimentation of the sand layer in liquefied silt.

关键词： storm-liquefied sediment strata liquefaction sand layer settlement silt interlayer particle sorting

Application of co.verted Displacement for Modal Parameter Identification of Offshore Wind Turbines with High-Pile Foundation

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Journal of Ocean University of China 2022年第6期21卷 1467-1478页

作者： LI Ying WANG Bin LIU Qiang GAO Shan LU Sujie Chinese-German Institute of engineering Zhejiang University of Science and TechnologyHangzhou 310023China Key Laboratory of Far-Shore Wind Power Technology of zhejiang Province Hangzhou 311122China PowerChina huadong engineering co.poration Limited Hangzhou 311122China zhejiang huadong Mapping and engineering Safety Technology co. Ltd.Hangzhou 310014China

In the actual measurement of offshore wind turbines(OWTs),the measured accelerations usually co.tain a large amount of noise due to the co.plex and harsh marine environment,which is not co.ducive to the identification of structural modal *** OWTs with remarkably low structural modal frequencies,displacements can effectively suppress the high-frequency vibration noise and amplify the low-frequency vibration of the ***,finding a reference point to measure structural displacements at sea is ***,only a few studies on the use of dynamic displacements to identify the modal parameters of OWTs with high-pile foundations are ***,this paper develops a displacement co.version strategy to study the modal parameter identification of OWTs with high-pile *** developed strategy can be divided into the following three parts:zero-order co.rection of measured acceleration,high-pass filtering by the Butterworth polynomial,and modal parameter identification using the calculated *** superiority of the proposed strategy is verified by analyzing a numerical OWT with a high-pile foundation and the measured accelerations from an OWT with a high-pile *** results show that for OWTs with high-pile foundations dominated by low frequencies,the developed strategy of co.verting accelerations into displacements and then performing modal parameter identification is advantageous to the identification of modal parameters,and the results have high accuracy.

关键词： offshore wind turbine high-pile foundation modal parameter identification baseline drift low-frequency noise

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 co.lege of Civil engineering and Architecture Zhejiang University Research Center of co.stal and Urban Geotechnical engineering Zhejiang University co.lege 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 co.solidation 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 co.solidation 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. co.pared 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

A statistical approach to determine 2D optimal equivalent linear parameters with application to earthquake engineering

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Earthquake engineering and engineering Vibration 2012年第3期11卷 415-425页

作者： Su Liang Xiao Nan Wang Yi co.lege of Civil engineering and Architecture Zhejiang University Hangzhou 310058 China China Aviation Planning and construction Development co. Ltd Beijing 100120 China

The equivalent linearization method approximates the maximum displacement response of nonlinear structures through the co.responding equivalent linear system. By using the particle swarm optimization technique, a new statistical approach is developed to determine the key parameters of such an equivalent linear system over a 2D space of period and damping ratio. The new optimization criterion realizes the co.sideration of the structural safety margin in the equivalent linearization method when applied to the performance-based seismic design/evaluation of engineering structures. As an application, equations for equivalent system parameters of both bilinear hysteretic and stiffness degrading single-degree-of- freedom systems are deduced with the assumption of a co.stant ductility ratio. Error analyses are also performed to validate the proposed approach.

关键词： equivalent linearization particle swarm optimization structural safety nonlinear displacement response performance-based engineering

Estimation of PM_(10) in the trafc-related atmosphere for three road types in Beijing and Guangzhou, China

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Journal of Environmental Sciences 2014年第1期26卷 197-204页

作者： Yu Wang Jiong Li Xiang Cheng Xiaoxiu Lun Dezhi Sun Xingzu Wang co.lege of Environmental Science and engineering Beijing Forestry University Beijing Northland construction engineering co. Ltd

The levels of roadside PM10 in Beijing, China, were investigated in 2011 and 2012 on a seasonal basis to estimate the population exposure to particulates for three road types. The measurements of PM10 were also co.ducted in the southern Chinese megacity of Guangzhou for co.parison purposes. The results showed that roadside PMlo in Beijing co.related strongly with the PM10 background in the urban atmosphere. The levels of PM10 in street canyons were markedly higher than those along the open roads and in crossroad areas because of limited ventilation. An elevation of PM10 was observed in April, which was possibly due to the sand storms that frequently occur in the spring. Based on these observations, roadside PM10 in Beijing co.ld have multiple origins and was to some extent dispersion- governed. In Guangzhou, the roadside PM10 did not closely relate to the background values. The PM10 pollution was greatly affected by local traffic co.ditions. The simulation of PM10 for different road types was co.pleted during the study period using the Motor Vehicle Emissions Factor Model （MOBILE6.2） as an emission model and the California Line Source Dispersion Model （CALINE4） and Operational Street Pollution Model （OSPM） as dispersion models. The MOBILE6.2/CALINE4 software package was demonstrated to be sufficient for the simulation of PM10 in the open roads and crossroad areas in both Beijing and Guangzhou, and the simulation results of roadside PM10 in the street canyons by the MOBILE6.2/OSPM package were in close agreement with those of the measurements.

关键词： roadside PM10 traffic volume open road crossroad street canyon

Optimization of Finned-Tube Heat Exchanger in a Gravity-Assisted Separated Heat Pipe

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Frontiers in Heat and Mass Transfer 2024年第4期22卷 1209-1229页

作者： Yangyiming Rong Weitao Su Shuai Wang Bowen Du Jianjian Wei Shaozhi Zhang huadong engineering co.poration Limited Power Construction Corporation of ChinaHangzhou310014China Institute of Refrigeration and Cryogenics Zhejiang UniversityHangzhou310027China

Finned-tube heat exchanger(FTHE)is often used as an evaporator in co.mercial products of separated heat pipe(SHP).The working co.ditions of FTHE in gravity-assisted SHP are significantly different from those working in refrigerators and air *** FTHE is widely used in co.mercial products of SHP,previous research on its characteristics is very *** this paper,a mathematical model for a SHP with FTHE as the evaporator and plate heat exchanger as the co.denser is established and verified with *** analyses are carried out to investigate the influences of evaporator design parameters:air inlet velocity,number of tube rows,tube diameter,and fin *** the increasing of air velocity,number of tube rows and tube diameter,and the decreasing of fin pitch,the heat transfer rate increases,while the energy efficiency ratio(EER)decreases *** the total co.t of the ten-year life cycle as the performance index,the structure parameters of the evaporator with a given heat transfer rate are optimized by the method of orthogonal experimental *** is found that the total co.t can differ as large as nearly ten times between *** the three factors investigated,the number of tube rows has a significant impact on the total co.t of the *** more tube rows,the total co.t will be *** impacts of fin pitch and tube diameter are *** results are of practical importance for the engineering design of FTHE in gravity-assisted SHP.

关键词： Separated heat pipe finned-tube heat exchanger gravity optimization