Xu Q.,Nanjing Audit University |
Li A.,Nanjing Southeast University |
Ding Y.,Nanjing Southeast University |
Shen S.,China Aviation Planning and Construction Development Co. |
Hu C.,Nanjing Audit University
Tumu Gongcheng Xuebao/China Civil Engineering Journal | Year: 2013
Dynamic characteristics of long-span hangar are very complex and the study on the shock absorption of this type of structure is just at the early stage. Combined with seismic response characteristics, fluid viscous dampers are set between columns and joints of the roof to reduce the seismic response. Based on the characteristics of optimization model of seismic reduction structure, the genetic optimization algorithm is employed for the optimization analysis of damper location. The algorithm is improved for the increased optimization efficiency and accuracy. By means of the Matlab toolbox, a damper program for the location optimization of seismic reduction structure is coded. Two types of fitness functions are provided and used for the damper location optimization of one hangar. Results show that the location optimization analysis may be conducted effectively by using the proposed optimization algorithm and the coded program.
Wang M.,Beijing Institute of Technology |
Deng Y.,China Aviation Planning and Construction Development Co. |
Chang X.,China Aviation Planning and Construction Development Co.
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2012
Out of a selection of 24 parameters from numerous factors which correlate to plane manhours in manufacture, six key parameters, including maximum takeoff weight, maximum speed, climbing rate, maximum overload, ratio of titanium/aluminum alloy and ratio of composite/aluminum alloy, are chosen via statistical and theoretical analysis based on existing plane samples. In view of the advantages of partial least-squares regression (PLS) method in analyzing multivariate data with small samples, it is utilized to build an estimation model of plane manhours in manufacture. The results show that the average error is about 10%. With this model, very little information, such as performance index, material composition, etc., is needed for the estimation of plane manufacturing manhours before the start of manufacturing activities. The PLS estimation model exhibits many advantages such as less parameters requirement, perspicuous physical meaning, and simple operation. It can be used to predict the manhours for plan optimization, design optimization, cost analysis and control, capital asset investment and production arrangement in the preliminary development stage of a plane with the absence of detailed design and manufacture information.
Li Z.,Tianjin University |
Li W.,Tianjin University |
Xu B.,China Aviation Planning and Construction Development Co
Applied Thermal Engineering | Year: 2016
A novel combined cooling, heating and powerorganic Rankine cycle (CCHP-ORC) system installed with heat pumps is presented in this paper. The CCHP-ORC system using zeotropic mixtures is first discussed, and this work is focused on selecting optimal zeotropic mixtures and determining the component concentration that gives a better performance. A system model under an idealized operating condition was built. The heat source is geothermal water whose temperature is 95 °C, and the mass flow is 40 t/h. The heat transfer fluid is heated to 45 °C for heating with the ambient temperature of -5 °C, and the refrigerating fluid is cooled to 0 °C with the ambient temperature of 35 °C. In this paper, 20 zeotropic mixtures were analyzed. The evaluation index net output power, heating capacity, refrigerating capacity, coefficient of performance (COP), economic thermal efficiency and exergy efficiency were calculated with the changing evaporation temperature under the condition of ejector coefficient 0.2. The ejector coefficient and evaporation temperature had been analyzed as independent variables. The results showed that R141b/R134a, R141b/R152a and R123/152a have a higher COP and exergy efficiency than others. By analyzing the component concentration of the optimized three kinds of zeotropic mixtures, it can be inferred that a mixture of dry and wet working fluids is more suitable for the system. The system gives rise to higher energy output if zeotropic mixtures are made of a higher proportion of wet working fluid and a lower proportion of dry working fluid. © 2015 Published by Elsevier Ltd.
Zhang G.,China Aviation Planning and Construction Development Co. |
Ge J.,China Aviation Planning and Construction Development Co. |
Wang S.,China Aviation Planning and Construction Development Co. |
Zhang A.,Beijing University of Technology |
And 3 more authors.
Jianzhu Jiegou Xuebao/Journal of Building Structures | Year: 2012
The structural system of cable dome with span of 71.2 m is employed for the roof structure of the National Fitness Center in Ejin Horo Banner, Inner Mongolia. It's the first large-span cable dome structure in mainland of our country. Firstly, the whole finite element model of cable dome structure was established and subjected to static analysis under various design and normal load combinations. That the unevenly distributed load was detrimental for cable dome structure was put forward by analyzing the force-bearing characteristics of cable dome structure at elastic stage. Secondly, the conclusions were drawn that the torsional stiffness of cable dome was weak and the membrane can improve the torsional stiffness effectively by analyzing dynamic characteristics. Subsequently, the whole process of elasto-plastic bucking analysis for cable dome system was performed to obtain the three stages in the whole loading process: relaxation of ridge cable, yielding of loop cable and breaking of structure. Meanwhile the influence of geometrical parameters on structural elasto-plastic performance was analyzed. Finally, the design method of cable dome structure based on performance was proposed, the strength and deformation performance and bearing capacity control indexes at each stage were put forward.
Liang S.,Zhejiang University |
Nan X.,Zhejiang University |
Yi W.,China Aviation Planning and Construction Development Co.
Journal of Earthquake Engineering and Engineering Vibration | Year: 2012
The equivalent linearization method approximates the maximum displacement response of nonlinear structures through the corresponding 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 consideration 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 constant ductility ratio. Error analyses are also performed to validate the proposed approach.
Zhao R.X.,China Aviation Planning and Construction Development Co. |
Wang X.J.,China Aviation Planning and Construction Development Co. |
Teng F.,China Aviation Planning and Construction Development Co.
2014 IEEE Chinese Guidance, Navigation and Control Conference, CGNCC 2014 | Year: 2015
The boiler drum water level not only has a profound effect on the steam generated quality and the stream-water separation speed, but also is an important parameter ensuring safety in production. In designing the PID controller, the selection of PID parameters has a direct impact on the control effect. Normally, the choice mainly based on experience with certain subjectivity. In this paper, genetic algorithms is applied to the PID controller design of steam boiler drum water level, reasonable objective function and weighted coefficients are designed according to the control requirements, and relatively optimal PID Parameters are obtained which not only meet the demanding control requirements but also optimize the dynamic performance and make the system have strong anti-interference ability. Finally, validity of the algorithms proposed is verified through computer simulation. © 2014 IEEE.
Zhang Q.,China Aviation Planning and Construction Development Co.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2011
A highrise building is characterized by large column grid. Central column load is much greater than side column load. In order to reduce the differential settlement between central column and side column, the optimization design of pile foundation considering variable rigidity is adopted. With central column pile 800 mm in diameter and 40 m in length and the side column pile 600 mm in diameter and 25 m in length, differential settlement problem is solved.
China Aviation Planning and Construction Development Co. | Date: 2014-09-29
A method of determining a prestressing force of a cable dome structure based on a cable dome tensioning and bearing whole process analysis, comprising: determining an initial geometry of a cable dome structure according to a construction geometry requirement and a construction function requirement; gradually increasing the prestressing force based on the initial prestressing force until a part of the cables of the cable dome structure exit the task, a ring cable reaches material yield, and the cable dome structure does not carry any load, and conducting a simulation analysis on elastoplasticity and geometrical non-linearity in a whole process of loading the structure by use of a load increment method; drawing a graph of structure displacement-whole bearing process and a graph of stress -whole bearing process; and determining the final design prestressing force of the cable dome structure according to a stable bearing capacity and a structural deformation capacity of the cable dome structure under the action of different times of initial prestressing force obtained based on the graph of structure displacement-whole bearing process and the graph of stress -whole bearing process.
China Aviation Planning and Construction Development Co. | Date: 2013-06-18
A cable-membrane tensegrity structure which is asymmetric, and construction method and design method thereof are provided. The cable-membrane tensegrity structure comprises a central opening and is formed by a ring cable (4) and three layers of radial cables comprising a suspension cable (1), a ridge cable (2) and a valley cable (3), wherein the suspension cable (1) is located above the ridge cable (2), the ridge cable (2) is located above the valley cable (3), wherein one end of each of the suspension cable (1), the ridge cable (2) and the valley cable (3) is connected to the ring cable (4), and the other end of each of the suspension cable (1), the ridge cable (2) and the valley cable (3) is connected to a peripheral supporting structure (7), wherein a coating membrane (5) is tensioned between the ridge cable (2) and the valley cable (3) that are adjacent to each other and function as a skeleton to tension the coating membrane (5). The method of constructing the cable-membrane tensegrity structure comprises steps of: lifting step by step the suspension cable (1), the ridge cable (2) and the valley cable (3) to positions adjacent to respective cable anchor nodes by a traction device, based on a shape of formed cable-membrane tensegrity structure; and tensioning and anchoring synchronously the suspension cable (1), the ridge cable (2) and the valley cable (3) in place by a tensioning device, so as to achieve a final shape of the cable-membrane tensegrity structure. A multi-stage design method, based on the bearing whole-process, of a cable-membrane tensegrity structure of an opening type is also provided.
China Aviation Planning and Construction Development Co. | Date: 2014-09-29
A method of designing a cable dome structure based on a cable dome bearing whole process analysis. The cable dome bearing whole process has three stages comprising a ridge cable relaxation, a ring cable yield and a structure failure.