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Liu Z.,Post Doctoral Research Center | Liu Z.,Tsinghua University | Zhang R.,Beijing Building Construction Research Institute Co.
Advanced Materials Research | Year: 2012

Cable is widely used in the actual project of prestressed steel structure for its mechanical properties can be fully used. Saddle-shaped cable net is a new type of large-span prestressed structure, but there is little study on the impact of different cable types on the mechanical properties of saddle-shaped cable net during the construction. In order to meet the thought of integration of design and construction, a finite element model of saddle-shaped cable net has been established. The four types of cables such as semi-parallel steel tendon cable, steel wire rope cable, steel strand cable and full-locked coil rope are chosen. The impact on mechanical properties of the structure was analyzed by different cable types. © (2012) Trans Tech Publications.

Liu Z.,Post Doctoral Research Center | Liu Z.,Beijing Building Construction Research Institute Co. | Liu Z.,Tsinghua University | Wang Z.,Beijing Building Construction Research Institute Co. | You D.,Beijing Building Construction Research Institute Co.
Applied Mechanics and Materials | Year: 2012

Based on the original construction experiences and techniques of cable dome, the method of integral assembling on the ground and synchronous hoisting of the structure of cable dome is firstly put forward. With the cable dome built in Ordos, the integral hoisting method and tension-shaping technique are put into effect. The results indicated the integral hoisting method can reduced aerial work and guaranteed constriction security. © (2012) Trans Tech Publications, Switzerland.

Chen J.-Q.,Central South University | Chen J.-Q.,Rutgers University | Li L.,Central South University | Zhao L.-H.,Central South University | And 3 more authors.
Journal of Central South University | Year: 2014

In order to simplify the boundary conditions of pavement temperature field, the "Environment-Surface" system which considered the natural environment and pavement surface was established. Based on this system, the partial differential equations of the one-dimensional heat conduction in the pavement were established on the basis of the heat transfer theory. Furthermore, the function forms of the initial and boundary conditions of the equations were created through the field experiments. The general solution of the pavement one-dimensional heat conduction partial differential equations was acquired by using Green's function, and the explicit expression of pavement temperature field under specific constraint conditions was derived. For the purpose of analysis, the pavement temperatures in different seasons were calculated using the explicit expression of pavement temperature field, and the calculation accuracy was analyzed through the comparison between measured and calculated values. Then, the relationship between fitting accuracy and calculation accuracy of pavement temperatures was analyzed. The analysis results show that: the usage of "Environment-Surface" system simplifies the calculation of pavement temperature field; the relative error between calculated and measured values is generally less than 7% and is seldom influenced by seasons; there is a positive correlation between the calculation accuracy and the fitting accuracy of pavement surface temperature; high fitting accuracy would result in less error of pavement temperature prediction. © 2014 Central South University Press and Springer-Verlag Berlin Heidelberg.

Dan H.-C.,Central South University | Dan H.-C.,Post doctoral Research Center | He L.-H.,Central South University | Zhao L.-H.,Post doctoral Research Center | And 2 more authors.
International Journal of Pavement Engineering | Year: 2015

Based on the Boit's theory, the governing equation was established to account for the response of moisture pavement. The analytical solutions were obtained through the expansion of Fourier series. Furthermore, the effects of parameters (i.e. hydraulic conductivity, traffic load velocity, drainage boundary and solid modulus) on dynamic response were investigated in terms of water-induced damage of pavement. Compared with the dry-elastic pavement, the negative normal stress in saturated asphalt pavement is concentrated beneath the traffic load, which may be a reason for a damage phenomenon in asphalt pavement. Hydraulic conductivity anisotropy plays a significant role in influencing the physical fields. Between vertical and horizontal hydraulic conductivity, the physical field almost depends on vertical hydraulic conductivity rather than horizontal hydraulic conductivity which just affects the horizontal pore-water velocity obviously. Moreover, the drained boundary evidently influences the seepage field of surface course with high permeability. © 2015 Taylor and Francis.

Jia F.,Beijing Jiaotong University | Jia F.,Post Doctoral Research Center | Jia F.,Beijing Building Construction Research Institute Co. | He K.,Beijing Building Construction Research Institute Co. | And 3 more authors.
Tiedao Xuebao/Journal of the China Railway Society | Year: 2016

Specimens with dimension of 100 mm×100 mm×100 mm were tested to investigate the influence of Reactive Powder Concrete (RPC) steel fiber content, interface treatment, pouring direction and strength of Normal Concrete (NC) on the splitting tensile bonding properties of RPC/NC, and to analyze bonding mechanism between the two. Experimental results showed that RPC/NC exhibited excellent bonding performance. Three failure modes included bonding interface failure, bonding interface failure with NC cracking and NC rupture. Steel fibers in RPC could enhance interfacial roughness, improve mechanical interlocking between RPC and NC, and crack resistance. Splitting tensile bonding strength increased with the increase of steel fibers. The interfacial roughness of RPC/NC was improved by using the cleaving surface as the bonding surface, resulting in higher splitting tensile bonding strength than that of the natural surface of the specimens. The splitting tensile bonding strength with horizontal pouring was greater than that with vertical pouring, about 1.1~1.3 times higher and increased with the increasing of NC strength. © 2016, Editorial Office of Journal of the China Railway Society. All right reserved.

Sun J.,General Hospital of Jinan Military Command | Sun J.,Post Doctoral Research Center | Yuan W.-A.,Shanghai University of Traditional Chinese Medicine | Lu H.,Shanghai University of Traditional Chinese Medicine | And 2 more authors.
International Journal of Clinical and Experimental Medicine | Year: 2015

Patient-Reported Outcomes (PROs) data are increasingly common and widely accepted in clinical investigations of symptoms. Agreements or differences regarding Doctor-Report Outcomes (DROs) VS PROs data are unclear. In this study, we conducted a clinical trial and investigated the agreement levels of DROs VS PROs in symptoms of diabetics. This study had a parallel self-controlled and double blind design. In total, 90 diabetics who presented with the required symptoms were enrolled in this study, and 83 patients completed the study. The severity (none, mild, moderate, and severe) of each symptom was consistently compared with the Visual Analogue Scale (VAS) for the PROs measure and the numerical rating scales (NRS) for the DROs measure. The Kappa index was used to test the agreement in the variables. Our results show that most of the agreements regarding DROs VS PROs were moderate; few were modest and substantial. However, the DROs data failed to agree with the PROs data well in which symptoms effective evaluation criteria overlapped with the inclusion criteria. We believe this results are caused by distortion of information during the doctor’s decision process. We suggest that the effective evaluation criteria should not be overlapped with the inclusion criteria in the DROs design. And if it is unavoidable, PROs design should be worth considering. © 2015, E-Century Publishing Corporation. All rights reserved.

Zhao N.,Zhejiang University | Zhao N.,Zhejiang Wanli University | Zhao N.,Post Doctoral Research Center | Li Y.,Zhejiang Wanli University | Liu N.,Zhejiang University
ICIC Express Letters | Year: 2014

Effective vendor selection is very important in supply chain management. Selecting right vendors and determining corresponding order quantities is a complex problem that takes into account many criteria. This paper considers vendor selection as a multi-criterion decision problem and a multi-objective programming model is developed for vendor selection. For easier solution, the model is converted into a single-objective one using the integrated weight of the criteria which is determined by a novel combination of AHP with DEA considering that the decision maker has different subjective and objective preference. A numerical experiment is exploited to test our method. The findings shall help the purchaser make a scientific decision. © ICIC International 2014.

Wang L.,Yangtze University | Deng L.,Post Doctoral Research Center | Jiao Y.,Chinese Academy of Agricultural Sciences
Acta Agriculturae Scandinavica Section B: Soil and Plant Science | Year: 2016

SymRK and GmFWL1 both play important roles in nodulation. However, during symbiotic development, the details of Nod factor signaling association with the regulation of cell division in nodules are unknown. SymRK, the immediately downstream component of these Nod factor receptors, is central to the Nod factor signaling cascade. In this study, specified RNAi plasmid of GmSymRK was constructed and transformed into soybean roots by agrobacterium rhizogenes-mediated hairy root transformation. We found that the nodule number decreased substantially in GmSymRK knockdown soybean transgenic roots. Further to study the relationship between GmFWL1 and Nod factor signaling, we analyzed the GmFWL1 expression levels in the GmSymRK RNAi soybean transgenic roots and found that rhizobia inoculation led to substantially reduced GmFWL1 expression in GmSymRK RNAi soybean transgenic roots. Our studies showed that the regulation of cell division was affected by Nod factor signaling during nodule development in soybean, which provides important information toward understanding the functions of GmSymRK and GmFWL1 in symbiotic signaling and nodule development. © 2016 Informa UK Limited, trading as Taylor & Francis Group

Dan H.-C.,Central South University | Dan H.-C.,Post doctoral Research Center | He L.-H.,Central South University | Xu B.,Central South University
Transport in Porous Media | Year: 2016

The unbound graded aggregate base (UGAB) has been widely used in drainage layers of highway pavements. This kind of material is of high permeability and can thus drain efficiently the water infiltrated through cracks in the pavement and reduce the associated water damage. The hydraulic conductivity of UGAB is a key factor describing the water flow behavior in UGAB and thus be considered primarily in the design of highway drainage engineering. In this study, the flow behavior of UGAB material was investigated through constant head permeability experiments. Based on the Reynolds number analysis, it was found that the flow in UGAB material was non-Darcian even though under relatively low hydraulic gradient. Therefore, the Darcy law cannot be directly applied to determine the hydraulic conductivity of UGAB. Furthermore, the empirical expression of coefficients in Forchheimer equation, which can be available to evaluate hydraulic conductivity of UGAB material approximately, is presented incorporating the representative particle size and porosity based on the Ergun equation. Then, it was validated against the aid of normalized objective function analysis. Through comparison analysis, the sequencing of hydraulic conductivity of UGAB material was sorted quantitatively in terms of different gradation and representative particle size ((Formula presented.) and (Formula presented.)). The results also showed that the (Formula presented.)(Formula presented.) and the content of fine particles (<0.075 mm) are appropriate indexes for the gradation design of UGAB material in highway pavement engineering. © 2016 Springer Science+Business Media Dordrecht

Dan H.-C.,Central South University | Dan H.-C.,Post doctoral Research Center | Dan H.-C.,National Engineering Laboratory for Mountain Traffic Disaster Prevention and Control Technology Guizhou | He L.-H.,Central South University | And 4 more authors.
Cold Regions Science and Technology | Year: 2014

Currently, there are few quantitative studies on the adhesion of ice to the asphalt pavement surface. In this paper, a large-scale freezing laboratory is employed to simulate the low-temperature and wet environment, and a full-scale asphalt pavement model is constructed in the freezing laboratory. The experimental schemes are developed to measure the magnitudes of the normal and horizontal adhesive force of ice to the rough asphalt pavement surface. Then, the normal and horizontal adhesive strength of ice is evaluated to quantify the adhesive force per unit rough area, and the effects of ice temperature as well as the mean texture depth of asphalt pavement on the ice adhesive strength are taken into consideration. Based on the test and evaluation results, it is found that the normal and horizontal ice adhesive strength increases with the ice temperature decrease. The adhesive strength in the normal direction exhibits a logarithmic relation to the ice temperature whereas that in the horizontal direction shows a linear relation. The adhesive strength of ice to the asphalt pavement with higher mean texture depth (0.65. mm) is stronger than that with the lower mean texture depth case (0.50. mm). © 2014 Elsevier B.V.

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