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19篇 您的检索式:作者名="ZHENG Changjie"
    题名 作者 年代 出处 被引量
1Torsional vibration of a pipe pile in transversely isotropic saturated soil显示文摘This study considers the torsional vibration of a pipe pile in a transversely isotropic saturated soil layer. Based on Biot's poroelastic theory and the constitutive relations of the transversely isotropic medium, the dynamic governing equations of the outer and inner transversely isotropic saturated soil layers are derived. The Laplace transform is used to solve the governing equations of the outer and inner soil layers. The dynamic torsional response of the pipe pile in the frequency domain is derived utilizing 1D elastic theory and the continuous conditions at the interfaces between the pipe pile and the soils. The time domain solution is obtained by Fourier inverse transform. A parametric study is conducted to demonstrate the influence of the anisotropies of the outer and inner soil on the torsional dynamic response of the pipe pile.Zheng Changjie Hua Jianmin Ding Xuanming 2016Earthquake Engineering and Engineering Vibration2016,15,3:8
2Model tests on XCC-piled embankment under dynamic train load of high-speed railways显示文摘Piled embankments,which offer many advantages,are increasingly popular in construction of high-speed railways in China.Although the performance of piled embankment under static loading is well-known,the behavior under the dynamic train load of a high-speed railway is not yet understood.In light of this,a heavily instrumented piled embankment model was set up,and a model test was carried out,in which a servo-hydraulic actuator outputting M-shaped waves was adopted to simulate the process of a running train.Earth pressure,settlement,strain in the geogrid and pile and excess pore water pressure were measured.The results show that the soil arching height under the dynamic train load of a high-speed railway is shorter than under static loading.The growth trend for accumulated settlement slowed down after long-term vibration although there was still a tendency for it to increase.Accumulated geogrid strain has an increasing tendency after long-term vibration.The closer the embankment edge,the greater the geogrid strain over the subsoil.Strains in the pile were smaller under dynamic train loads,and their distribution was different from that under static loading.At the same elevation,excess pore water pressure under the track slab was greater than that under the embankment shoulder.Niu Tingting Liu Hanlong Ding Xuanming Zheng Changjie 2018Earthquake Engineering and Engineering Vibration2018,17,3:6
3Causal effects of shelter forests and water factors on desertification control during 2000–2010 at the Horqin Sandy Land region, China显示文摘The Horqin Sandy Land(HSL), the largest sandy land in the semi-arid agro-pastoral ecotone of Northeast China, has been subject to desertification during the past century. In response, and to control the desertification,government implemented the Three-North Shelter/Protective Forest Program, world's largest ecological reforestation/afforestation restoration program. The program began in1978 and will continue for 75 years until 2050. Understanding the dynamics of desertification and its driving forces is a precondition for controlling desertification.However, there is little evidence to directly link causal effects with desertification process(i.e., on the changing area of sandy land) because desertification is a complex process,that can be affected by vegetation(including vegetation cover and extent of shelter forests) and water factors such as precipitation, surface soil moisture, and evapotranspiration.The objectives of this study were to identify how influencing factors, especially shelter forests, affected desertification in HSL over a recent decade. We used Landsat TM imagery analysis and path analysis to identify the effects of spatiotemporal changes in water and vegetation parameters during2000–2010. Desertification was controlled during the study period, as indicated by a decrease in desert area at a rate of163.3 km2year-1and an increase in the area with reduced intensity or extent of desertification. Total vegetation cover in HSL increased by 10.6 % during the study period and this factor exerted the greatest direct and indirect effects on slowing desertification. The contribution of total vegetation cover to controlling desertification increased with the intensity of desertification. On slightly and extremely severe desertified areas, vegetation cover contributed 5 and 42 % of the desertification reduction, respectively. There were significant correlations between total vegetation cover and water conditions(i.e., evapotranspiration and precipitation)and the area of shelter forests(P \ 0.0001), in which water conditions and the existence of shelter forests contributed49.7 and 12.8 % to total vegetation cover, respectively. The area of shelter forests increased sharply due to program efforts, but only shrub forests had significant direct effects on reducing the area of desertification categorized as slightly desertified. The reason for the lack of direct effect of increased arbor forests(accounting for 95.3 % of the total increase in shelter forests) on reducing desertification might be that the selected arbor species were not suited to water conditions(low precipitation, high evapotranspiration) prevailing at HSL. The establishment of shelter forests aided control of desertification in the HSL region, but the effect was less than expected. Effective control of desertification in the HSL region or other similar sandy areas will require greater improvements in vegetation cover. In particular,shrub species should be selected for plantation with reference to their potential to survive and reproduce in the harsh climatic and weather conditions typical of desertified areas.Qiaoling Yan Jiaojun Zhu Xiao Zheng Changjie Jin 2015Journal of Forestry Research2015,26,1:5
4Modelling long-term deformation of granular soils incorporating the concept of fractional calculus显示文摘Many constitutive models exist to characterise the cyclic behaviour of granular soils but can only simulate deformations for very limited cycles. Fractional derivatives have been regarded as one potential instrument for modelling memory-dependent phenomena. In this paper, the physical connection between the fractional derivative order and the fractal dimension of granular soils is investigated in detail.Then a modified elasto-plastic constitutive model is proposed for evaluating the long-term deformation of granular soils under cyclic loading by incorporating the concept of factional calculus. To describe the flow direction of granular soils under cyclic loading, a cyclic flow potential considering particle breakage is used. Test results of several types of granular soils are used to validate the model performance.Yifei Sun Yang Xiao Changjie Zheng Khairul Fikry Hanif 2016Acta Mechanica Sinica2016,32,1:5
5Breakage and shape analysis of ballast aggregates with different size distributions显示文摘Yifei Sun Changjie Zheng 2017Particuology2017,15,6:4
6Numerical and test study on vertical vibration characteristics of pile group in slope soil topography显示文摘Topography effects on the vertical vibration responses of pile group are revealed though numerical analysis and model tests.First,a series of model tests with different topography of ground and bedrock are conducted.The results indicate that displacement amplitude of the pile head in sloping ground topography is larger than in horizontal ground.Differential displacement at various positions of the pile cap is observed in non-horizontal topography.Afterwards,a numerical algorithm is employed to further explore the essential response characteristics in group piles of different topography configurations,which has been verified by the test results.The lengths of the exposed and frictional segment,together with the thickness of the subsoil layer,are the dominant factors which cause non-axisymmetric vibration at the pile cap.Qu Liming Ding Xuanming Zheng Changjie Wu Chongrong Cao Guangwei 2021Earthquake Engineering and Engineering Vibration2021,20,2:3
7An Analytical Solution for Wave Propagation in a Pipe Pile with Multiple Defects显示文摘An analytical solution is developed in this paper to conduct the low-strain integrity testing for a pipe pile with multiple defects.The derived solution allows simulating the pipe pile as a three-dimensional model by considering the wave propagation in the vertical,circumferential and radial directions.Analytical solutions of the pile are obtained by the Laplace transform and separation of variables.Accordingly,time-domain responses of the solution are deduced by the inverse Fourier transform numerically.The solution is validated against the published solutions for an intact pile and a pile with a single defect.Parametric studies are conducted to identify and characterize the velocity responses on the top of pipe piles with multiple defects.Numerical results suggest that the reflected waves generated by the deep defects are affected by the secondary reflections from the shallow defects.A new detecting method is proposed to decrease the influence of high-frequency interferences and to predict the defective depth,which suggests putting the receiver at the point of 90°along the circumferential direction.Xuanming Ding Lubao Luan Changjie Zheng Guoxiong Mei Hang Zhou 2020Acta Mechanica Solida Sinica2020,33,2:2
8Petrogenesis of Jurassic Granitoids on Liaodong Peninsula,Northeast China:Constraints on the Evolution of the Mongol-Okhotsk and Pacific Tectonic Regimes显示文摘The tectonic setting of Jurassic magmatism in the Northeast China(NE China)is unclear.Here,we present new petrological,whole-rock geochemical,zircon U-Pb geochronological,and zircon Lu-Hf isotope data for Jurassic granitoids of the Wulong region,Liaodong Peninsula,NE China.Laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)zircon U-Pb data indicate that these granitoids were emplaced at 165-156 Ma.The biotite monzogranite,two-mica monzogranite,monzogranite,granodiorite,biotite granodiorite,and syenogranite are strongly peraluminous(A/CNK=1.09-1.29),contain peraluminous minerals such as muscovite,have high normative corundum abundances(1.26 wt.%-3.28 wt.%),and have high K2_(O)/Na2O ratios(0.76-1.48),all of which indicate an S-type granite affinity.However,the biotite granodiorite and syenogranite have high Sr(391 ppm-570 ppm)and low Y(3.06 ppm-5.94 ppm)contents,with high Sr/Y(65.8-185.9)ratios,and the two-mica monzogranite,monzogranite,and granodiorite have relatively high Sr(138 ppm-379 ppm)and low Y(3.38 ppm-8.71 ppm)contents,with high Sr/Y ratios(19.1-77.9).All of the analyzed samples have negative zircon eHf(t)values(-41.4 to-20.6)with old two-stage Hf model ages(TDM2(Hf)=2.50-3.76 Ga).Therefore,we infer that the biotite monzogranite is the typical feature of S-type granite that was derived by partial melting of metagraywacke.The monzogranite,two-mica monzogranite,granodiorite,biotite granodiorite,and syenogranite exhibit geochemical characteristics of S-type granite with K-rich adakitic features,and were possibly derived by mixing of melts from clastic crustal materials and ada-kitic magmas.There are voluminous Jurassic igneous rocks in the NE China.By combining our study with the previous researches,this paper infers that the Jurassic magmatism within the Erguna-Xing'an Massif was related to the southward subduction and closure of the Mongol-Okhotsk Ocean;the Early Jurassic magmatism to the east of the Songliao Basin and in the northern North China Cra-ton(NCC)was related to the subduction of the Pacific Plate;however,the Middle-Late Jurassic igne-ous rocks to the west of the Songliao Basin were related to the closure of the Mongol-Okhotsk Ocean and,in the northern NCC,were related to closure of the Mongol-Okhotsk Ocean with an influence from flat-slab subduction of the Pacific Plate.Jinyu Li Ye Qian Leontine Tekoumc Changji Zhao Jinlei Sun Tao Zheng Fengyue Sun Yanjie Shen 2021Journal of Earth Science2021,32,1:2
9Horizontal dynamic response of a large-diameter pipe pile considering the second-order effect of axial force显示文摘The second-order effect of axial force on horizontal vibrating characteristics of a large-diameter pipe pile is theoretically investigated.Governing equations of the pile-soil system are established based on elastodynamics.Threedimensional wave equations of soil are decoupled through differential transformation and variable separation.Consequently,expressions of soil displacements and horizontal resistances can be obtained.An analytical solution of the pile is derived based on continuity conditions between the pile and soil,subsequently from which expressions of the complex impedances are deduced.Analyses are carried out to examine the second-order effect of axial force on the horizontal vibrating behavior of the pipe pile.Some conclusions can be summarized as follows: stiffness and damping factors are decreased with the application of axial force on the pile head; distributions of the pile horizontal displacement and rotation angle are regenerated due to the second-order effect of the applied axial force; and redistributions of the bending moment and shearing force occur due to the second-order effect of the applied axial force.Luan Lubao Ding Xuanming Zhou Wei Zheng Changjie Qu Liming 2018Earthquake Engineering and Engineering Vibration2018,17,3:2
10Vertical dynamic response of a pipe pile in saturated soil layer显示文摘Liu Hanlong Zheng Changjie Ding Xuanming 2014Computers andGeotechnics2014,61,9:1
11Torsional dynamic response of a large-diameter pipe pile in viscoelastic saturated soil显示文摘Zheng Changjie Liu Hanlong Ding Xuanming 2014International Journal for Numerical and Analytical Methods in Geomechanics2014,38,16:1
12Coupled vibration of a concrete pipe pile with saturat- ed soil due to longitudinal loading 显示文摘ZHENG Changjie DING Xuanming AN Shuhong 2015J Vibroengin2015,17,28:1
13Vertical vibration of a large diameter pipe pile consid- ering transverse inertia effect of pile 显示文摘ZHENG Changjie LIU Hanlong DING Xuanming 2016J Cent South Univ2016,23,89:1
14Division and correlation of Yixian Formation in western Liaoning,China显示文摘The Yixian Formation is a series of volcanic-sedimentary rocks in Biepiao area of Liaoning Province. It is mainly composed of basic and intermediate-basic volcanic lava,pyroclasts and terrestrial sedimentary rocks. Based on the regularity of volcanic activity,the Yixian Formation was divided by the present authors into four members in ascending order:the first member is of basal conglomerate,basic and intermediate-basic volcanic rocks; the second member is of lake phrase sedimentary rocks,or in another word,precious fossil-rich sedimentary beds; the third is of basic volcanic rocks; and the fourth is of upper conglomerate. Field mapping and comprehensive study also indicate that there are abundant vertebrate fossils (mainly of Psittacosaurus) in the first member of the Yixian Formation,and the Jehol Biota (including Sinosauropterxy,Confuciusorns sanctus,Archaefructus,etc.) is yielded in the second member of Yixian Formation. From west to east,the volcanic activity of Yixian Formation changed regularly from early to late,and from basic and intermediate-basic to acid (alkali).ZHAO Liang XING Dehe' SUN Chulin SUN Yuewu ZHANG Lidong GUO Shengzhe ZHANG Changjie PENG Yandong JIA Bin CHEN Shuwang DING Qiuhong ZHENG Yuejuan 2010Global Geology2010,13,3:0
15Research on Landscape Energy-Saving Integrated Water Curtain System显示文摘Aiming at the serious heat and cold loss of the building glass curtain wall in the field of amusement and tourism,and the need to meet the landscape requirements of the building facade,this paper put forward the idea of integrating the shading and consumption reduction of glass curtain wall with the landscape requirements,that is,the water curtain was set outside the glass curtain wall to form a landscape energy-saving integrated water curtain wall system,while meeting the needs of landscape and shading.By establishing the numerical calculation model of the system,the corresponding relationship between the thickness of water film and the weakening of solar radiation intensity was revealed,as well as the influence of wind speed and wind direction on the nozzle exit angle and velocity selection;and the synergistic law of air flow rate and air temperature drop amplitude.The results showed that the water film thickness at 3-4 cm can reduce the solar radiation by 65%-80%.The temperature of the air layer between the water film and the curtain wall decreased as the air flow rate decreased,when the thickness of water film was 2 cm and the air velocity was 0.5-1.5 m/s,the air temperature dropped to 2.47-3.6°C.Finally,through the analysis of the actual project-ICE World&WATER Park,the system can reduce 66.8%of solar radiation,and reduce the air layer temperature by 3.9°C.GUO Pengxin LI Hongqiang HE Changjie ZHENG Yingfa LI Shuisheng ZHANG Guoqiang 2019Journal of Thermal Science2019,28,6:0
16Dynamic response of a pile embedded in elastic half space subjected to harmonic vertical loading显示文摘An analytical method is developed to investigate the dynamic response of a pile subjected to harmonic vertical loading.The pile is modeled as a one-dimensional(1D)elastic rod.The elastic soil is divided into a homogeneous half space underlying the base of pile and a series of infinitesimally thin layers along the vertical shaft of pile.The analytical solution for the soil-pile dynamic interaction problem is obtained by the method of Hankel transformation.The proposed solution is compared with the classical plane strain solution.Arithmetical examples are presented to demonstrate the sensitivity of the vertical impedance of the pile to relevant parameters.Changjie Zheng Shishun Gan Xuanming Ding Lubao Luan 2017Acta Mechanica Solida Sinica2017,30,6:0
17Asyncflow: A visual programming tool for game artificial intelligence显示文摘Visual programming tools are widely applied in the game industry to assist game designers in developing game artificial intelligence(game AI)and gameplay.However,testing multiple game engines is a time-consuming operation,which degrades development efficiency.To provide an asynchronous platform for game designers,this paper introduces Asyncflow,an open-source visual programming solution.It consists of a flowchart maker for game logic explanation and a runtime framework integrating an asynchronous mechanism based on an event-driven architecture.Asyncflow supports multiple programming languages and can be easily embedded in various game engines to run flowcharts created by game designers.©2021 The Authors.Zhipeng Hu Changjie Fan Qiwei Zheng Wei Wu Bai Liu 2021Visual Informatics2021,5,4:0
18Interfacial properties of 2D WS_(2)on SiO_(2)substrate from X-ray photoelectron spectroscopy and firstprinciples calculations显示文摘Two-dimensional(2D)WS_(2)films were deposited on SiO_(2)wafers,and the related interfacial properties were investigated by high-resolution X-ray photoelectron spectroscopy(XPS)and first-principles calculations.Using the direct(indirect)method,the valence band offset(VBO)at monolayer WS_(2)/SiO_(2)interface was found to be 3.97 eV(3.86 eV),and the conduction band offset(CBO)was 2.70 eV(2.81 eV).Furthermore,the VBO(CBO)at bulk WS_(2)/SiO_(2)interface is found to be about 0.48 eV(0.33 eV)larger due to the interlayer orbital coupling and splitting of valence and conduction band edges.Therefore,the WS_(2)/SiO_(2)heterostructure has a Type I energy-band alignment.The band offsets obtained experimentally and theoretically are consistent except the narrower theoretical bandgap of SiO_(2).The theoretical calculations further reveal a binding energy of 75 meV per S atom and the totally separated partial density of states,indicating a weak interaction and negligible Fermi level pinning effect between WS_(2)monolayer and SiO_(2)surface.Our combined experimental and theoretical results provide proof of the sufficient VBOs and CBOs and weak interaction in 2D WS_(2)/SiO_(2)heterostructures.Changjie Zhou Huili Zhu Weifeng Yang Qiubao Lin Tongchang Zheng Lan Yang Shuqiong Lan 2022Frontiers of physics2022,17,5:0
19Energy band alignment of 2D/3D MoS_(2)/4H-SiC heterostructure modulated by multiple interfacial interactions显示文摘The interfacial properties of MoS_(2)/4H-SiC heterostructures were studied by combining first-principles calculations and X-ray photoelectron spectroscopy.Experimental(theoretical)valence band offsets(VBOs)increase from 1.49(1.46)to 2.19(2.36)eV with increasing MoS_(2) monolayer(1L)up to 4 layers(4L).A strong interlayer interaction was revealed at 1L MoS_(2)/SiC interface.Fermi level pinning and totally surface passivation were realized for 4H-SiC(0001)surface.About 0.96e per unit cell transferring forms an electric field from SiC to MoS_(2).Then,1L MoS_(2)/SiC interface exhibits type I band alignment with the asymmetric conduction band offset(CBO)and VBO.For 2L and 4L MoS_(2)/SiC,Fermi level was just pinning at the lower MoS_(2)1L.The interaction keeps weak vdW interaction between upper and lower MoS_(2) layers.They exhibit the type II band alignments and the enlarged CBOs and VBOs,which is attributed to weak vdW interaction and strong interlayer orbital coupling in the multilayer MoS_(2).High efficiency of charge separation will emerge due to the asymmetric band alignment and built-in electric field for all the MoS_(2)/SiC interfaces.The multiple interfacial interactions provide a new modulated perspective for the next-generation electronics and optoelectronics based on the 2D/3D semiconductors heterojunctions.Huili Zhu Zifan Hong Changjie Zhou Qihui Wu Tongchang Zheng Lan Yang Shuqiong Lan Weifeng Yang 2023Frontiers of physics2023,18,1:0
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