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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 co.struction 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 co.struction,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 co.struction 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 co.struction ***,the optimal co.struction 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

16.48% Efficient solution-processed CIGS solar cells with crystal growth and defects engineering enabled by Ag doping strategy

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Journal of Energy Chemistry 2025年第1期100卷 59-65页

作者： Mengyu Xu Shaoco.g Yan Ting Liang Jia Jia Shengjie Yuan Dongxing Kou Zhengji Zhou Wenhui Zhou Yafang Qi Yuena Meng Litao Han Sixin Wu Key Laboratory for special Functional Materials of MOE National & Local Joint Engineering Research Centre for High-efficiency Display and Lighting Technology School of Nanoscience and Materials Engineering Henan University

Solution-processed Cu（In,Ga）Se2（CIGS） solar cells suffer from serious carrier reco.bination and power co.version efficiency（PCE） loss because of the poor film properties and easy formation of ***, we propose Ag&Se co.selenization strategy to enhance the crystallization and passivate harmful defects of the CIGS films. The formation of Ag-Se phase during the selenization process enables the formation of large grains and suppresses the deep level defects. It is found that Ag doping can enlarge the depletion region width, lower the Urbach energy and prolong the carrier lifetime. As a result, a champion solution-processed CIGS solar cell presents a high efficiency of 16.48% with the highly improved opencircuit voltage（VOC） of 662 m V and fill factor（FF） of 75.8%. This work provides an efficient strategy to prepare high quality solution-processed CIGS films for high-performance CIGS solar cells.

关键词： CIGS solar cells Solution-processed method Ag doping Crystal growth Defects engineering

co.relation Between Yield Stress of Silty Mud Sediments and co.tinuous Oscillatory Shearing Properties

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China Ocean engineering 2022年第2期36卷 223-232页

作者： CHEN Xiao-hui ZHANG Min-xi YUE Shao-lin ZHOU Huan YU Guo-liang SKLOE CISSEDepartment of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China cccc road&bridge special engineering co. Ltd.Wuhan 430061China

Analyzing the rheological properties of silty beds subjected to co.tinuous oscillatory shear loading is crucial for understanding the morphological deformation of the seabed and ensuring safety in geological and marine engineering *** this study,the effects of oscillatory shearing properties on the yield stress(S_(u))of silty sediments were quantitatively *** effects of oscillatory shear strength(0-3),water co.tent(26.6%-70.84%),and particle diameter(8.79-50μm)were examined extensively through a series of laboratory *** results indicated that the three aforementioned parameters were the major factors that affected the rheological characteristics of silty ***,their effects co.ld be elucidated using the yield stress of co.esive sediments as the indicator *** ratio of yield stress(S_(u)/S_(u0))varied as the oscillatory shear strength increased up to a critical value,Λ_(cr).S_(u)bsequently,the ratio remained at a co.stant *** was deduced that the yield stress decreased with increasing oscillatory shear strength forΛΛ_(cr),the sediments entered an equilibrium fluidization stage,and the yield stress remained almost co.stant,irrespective of the oscillatory shear ***,during the equilibrium fluidization stage,it was observed that the ratio S_(u)/S_(u0)did not vary with water co.tent but decreased as the particle diameter ***,based on regression analysis of the experimental data for non-equilibrium and equilibrium fluidization stages,a co.relation between yield stress of silty sediments and co.tinuous oscillatory shearing properties was *** co.relation can aid in understanding the changes in solid resistance and assessing safety in piling ***,it can provide a theoretical guidance for reducing soil resistance in marine structures using mechanical vibrations.

关键词： silty sediments yield stress water co.tent particle diameter oscillatory shear strength

Response spectra for nuclear structures on rock sites co.sidering the near-fault directivity effect

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Earthquake engineering and engineering Vibration 2010年第3期9卷 357-365页

作者： Xu Longjun Yang Shengchao Xie Lili Department of Civil engineering Harbin Institute of Technology at Weihai Weihai 264209 China cccc Highway and bridge co.sultants co. Ltd. Beijing 100029 China

Near-fault ground motions, potentially with large amplitude and typical velocity pulses, may significantly impact the performance of a wide range of structures. The current study is aimed at evaluating the safety implications of the near-fault effect on nuclear power plant facilities designed acco.ding to the Chinese co.e. To this end, a set of near- fault ground motions at rock sites with typical forward-directivity effect is examined with special emphasis on several key parameters and response spectra. Spectral co.parison of the selected reco.ds with the Chinese and other co.e design spectra was co.ducted. The bi-normalized response spectra in terms of different co.er periods are utilized to derive nuclear design spectra. It is co.cluded that nuclear design spectra on rock sites derived from typical rupture directivity reco.ds are significantly influenced both by the earthquake magnitude and the rupture distance. The nuclear design spectra specified in the co.e needs to be adjusted to reflect the near-fault directivity effect of large earthquakes.

关键词： near-fault ground motion directivity response spectrum rock site nuclear design

Seismic response analysis of road vehicle-bridge system for co.tinuous rigid frame bridges with high piers

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Earthquake engineering and engineering Vibration 2012年第4期11卷 593-602页

作者： Li Yongle Chen Ning Zhao Kai Liao Haili Department of Civil engineering Southwest Jiaotong University cccc Highway co.sultants co. Ltd.

The objective of this study is to investigate the effects of earthquakes on road vehicle-bridge co.pling vibration systems. A two-axle highway freight vehicle is treated as a 13 degree-of-freedom system co.posed of several rigid bodies, which are co.nected by a series of springs and dampers. The framework of the earthquake-vehicle-bridge dynamic analysis system is then established using an earthquake as the extemal excitation. The equivalent lateral co.tact force serves as the judgment criteria for sideslip accidents acco.ding to reliability theory. The entire process of the vehicle crossing the bridge is co.sidered for a very high pier co.tinuous rigid frame bridge. The response characteristics of the vehicle and the bridge are discussed in terms of various parameters such as earthquake ground motion, PGA value of the earthquake, incident angle, pier height, vehicle speed and mass. It is found that seismic excitation is the most influential factor in the responses of the vehicle-bridge system and that the safety of vehicles crossing the bridge is seriously impacted by the dual excitations of earthquake and bridge vibration.

关键词： vehicle-bridge system co.pling vibration seismic effects safety dynamic response

Hurricane damage assessment for residential co.struction co.sidering the non-stationarity in hurricane intensity and frequency

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Acta Oceanologica Sinica 2016年第12期35卷 110-118页

作者： WANG Cao LI Quanwang PANG Long ZOU Aming ZHANG Long Department of Civil engineering Tsinghua University cccc Highway co.sultants co. Ltd.

Natural hazards such as hurricanes may cause extensive eco.omic losses and social disruption for civil structures and infrastructures in co.stal areas, implying the importance of understanding the co.struction performance subjected to hurricanes and assessing the hurricane damages properly. The intensity and frequency of hurricanes have been reported to change with time due to the potential impact of climate *** this paper, a probability-based model of hurricane damage assessment for co.stal co.structions is proposed taking into acco.nt the non-stationarity in hurricane intensity and frequency. The nonhomogeneous Poisson process is employed to model the non-stationarity in hurricane occurrence while the non-stationarity in hurricane intensity is reflected by the time-variant statistical parameters(e.g., mean value and/or standard deviation), with which the mean value and variation of the cumulative hurricane damage are evaluated explicitly. The Miami-Dade co.nty, Florida, USA, is chosen to illustrate the hurricane damage assessment method proposed in this paper. The role of non-stationarity in hurricane intensity and occurrence rate due to climate change in hurricane damage is investigated using some representative changing patterns of hurricane parameters.

关键词： hurricane damage assessment intensity frequency non-stationarity climate change

Sulphate attack resistance of high-performance co.crete under co.pressive loading

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2013年第7期14卷 459-468页

作者： Hui XU Yu-xi ZHAO Lei CUI Bi XU Institute of Structural engineering Zhejiang University School of Civil engineering Newcastle University cccc Tianjin Dredging co. Ltd.

In this paper, an experimental study on the sulphate attack resistance of high-performance co.crete (HPC) with two different water-to-binder ratios (w/b) under co.pressive loading is presented. The sulphate co.centration, co.pressive strength, and the mass change in the HPC specimens were determined for immersion in a Na2SO4 solution over different durations under external co.pressive loading by self-regulating loading equipment. The effects of the co.pressive stress, the w/b ratio, and the Na2SO4 solution co.centration on the HPC sulphate attack resistance under co.pressive loading were analysed. The results showed that the HPC sulphate attack resistance under co.pressive loading was closely related to the stress level, the w/b ratio, and the Na2SO4 solution co.centration. Applying a 0.3 stress ratio for the co.pressive loading or reducing the w/b ratio clearly improved the HPC sulphate attack resistance, whereas applying a 0.6 stress ratio for the co.pressive loading or exposing the HPC to a more co.centrated Na2SO4 solution accelerated the sulphate attack and HPC deterioration.

关键词： Sulphate attack resistance High-performance co.crete (HPC) co.pressive loading

Intelligent feedback analysis on a deep excavation for the gravity anchorage foundation of a super suspension bridge

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岩石力学与工程学报 2019年第A1期38卷 2898-2912页

作者： RAN Tao LIU Daan MEI Songhua WANG Weiwei TAN Lihua Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences Zhongnan engineering co. Ltd. cccc First Highway engineering co. Ltd.

In order to ensure the co.struction safety of the 38.5 m deep excavation for the gravity anchorage foundation of Fuma Yangtze River bridge, an intelligent feedback analysis was applied to this excavation project. First, a three-dimensional numerical model that simulating the co.struction process of the excavation was built,and the deformations of the supporting structures were calculated by the finite difference program FLAC3 D. Then,the non-linear mapping relationship between the geomechanical parameters and the excavation-induced displacements was established by the back-propagation neural network(BPNN). Last,the geomechanical parameters were optimized intelligently by the genetic algorithm(GA) based on the developed BPNN model and the measured displacements,and the deformations during the subsequent excavation stages were predicted based on the back-calculated parameters. The research results showed that:the back-calculated values of E1,μ1,c1,and φ1 of the co.pletely weathered stratum,and E2 of the heavily weathered stratum were greater than the initial values,while the inversion value of E3 of the moderately weathered stratum was smaller than the initial value. The magnitudes and the variation tendencies of the predicted displacements were in good acco.dance with the measured displacements. At the end of the excavation,the retaining piles and the top beams had a maximum displacement of 15–20 mm,exhibiting a quite small magnitude as co.paring with other case histories. Local co.centration of shear stress mainly occurred at the soil-pile interface and at the toe of the excavation slope,and the plastic zones mainly appeared in the co.pletely weathered stratum. After the co.pletion of the excavation,there were no yielding elements in the model,and the co.vergence of the numerical co.putation was achieved,indicating the excavation was in a stable state. This study lays the basis for the subsequent co.struction and operation of the bridge,and offers a significant refe

关键词： foundations suspension bridge anchorage deep excavation parameter inversion deformation prediction intelligent feedback analysis

Multi-objective and multi-scheme research on water and sediment regulation potential of reservoirs in the upper Yellow River

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International Journal of Sediment Research 2023年第2期38卷 203-215页

作者： Tao Bai Jia Yu Wenting Jin Jiaquan Wan Shaojie Gou Xu Ma Panpan Ma Xi'an University of Technology Ankang University Chengdu engineering co. Ltd. cccc First Highway co.sultants co. Ltd.

The problems of the deteriorating relation between water and sediment, and the escalating co.flict between water supply and demand in the upper Yellow River(YR), need to be addressed. Reservoirs of Longyangxia, Liujiaxia, and Heishanxia(Long-Liu-Hei) in the upper YR are taken as the research object, and a multi-objective, water-sediment optimal operation model for cascade reservoirs Long-Liu-Hei has been developed. This operation model co.siders the co.prehensive requirements of water supply, power generation, flood co.trol, and especially, water and sediment regulation. The improved Non-dominated Sorting Genetic Algorithms(NSGA-II) method is used to demonstrate the water and sediment regulation potential of three scenario schemes under long-term co.ditions, and the adjustable water allocation of four schemes under typical year co.ditions are calculated. It is reco.mended to use the mode of generating hydropower depending on the available water amount as the best operating mode under the co.ditions of a long time series and for typical years. This reco.mended operation mode has verified the rationality and accuracy of the reservoir operations *** the same time, co.pared with the calculation results for water and sediment regulation after the co.struction of the Heishanxia, the current research indicates:(1) Under the reco.mended model, the potential for water and sediment regulation under the long-term series and typical years is once every four years.(2) Inter-basin water transfer greatly improves the cascade power generation. When the adjustable water volume is co.verted into the co.trolled volume for water and sediment regulation,the intensity frequency of water and sediment regulation of cascade reservoirs are improved.(3) With the intensification of the co.tradiction between the supply of and demand for water resources in the upper YR in the future, the amount of transferable water exhibits a decreasing trend, and the regulation of water and sediment in th

关键词： Water and sediment regulation Multi-objective regulation Cascade of reservoirs Regulatory potential

Estimating the resistance of aging service-proven bridges with a Gamma process-based deterioration model

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Journal of Traffic and Transportation engineering(English Edition) 2019年第1期6卷 76-84页

作者： Cao Wang Kairui Feng Long Zhang Aming Zou School of Civil engineering The University of Sydney Department of Civil engineering Tsinghua University cccc Highway co.sultants co. Ltd.

The environmental or anthropogenic factors, to which the in-service bridges are subjected,are responsible for the reduction of bridge performance, and finally lead to great service risk for bridges and increase the probability of substantial eco.omic losses. Probabilitybased estimate of bridge resistance is an essential indicator for the bridge co.dition evaluation and for optimization of bridge maintenance/repair decisions. It places an emphasis on the proper probabilistic models of structural properties and assessment methods. Making full use of historical service load information may improve the accuracy of bridge performance assessment with reduced epistemic uncertainty for existing aging bridges. In to-date analyses to update the bridge resistance with past service information,the models of resistance deterioration have been assumed as either deterministic or fully co.related, which may differ significantly from the realistic case. With this regard, this paper proposes a novel method for updating the resistance of service-proven bridges with a realistic deterioration model. The Gamma stochastic process has been suggested in the literature to describe the probabilistic behavior of structural time-dependent resistance and thus is adopted in this paper. An illustrative bridge is presented to demonstrate the applicability of the proposed method. Parametric examples are co.ducted to investigate the role of resistance deterioration model in the updated estimate of bridge resistance with historical service information.

关键词： Existing aging bridges Historical load information Resistance updating Gamma deterioration process bridge safety