COMPUTER-AIDED ANALYSIS AND DESIGN FOR THE BASE STRUCTURE OF A MOVABLE TOWER CRANE

This paper is one of the achievements of the researchitem for computer-aided design of tower crane's steel structure.In thepaper,taking the well-base structure as an example,first the method establishing the mechanical model is explained for the base structure ofa movable tower crane.Then the math model of its optimal design andthe N-S figures for the computer program is described and calculatedusing discrete optimal technology.Finally the problems related to thedesign for the base structure of a movable tower crane are briefly illu-strated.     

Model Analysis of Tower Crane Structure Based on ANSYS

In this paper,a complete dynamic model of the tower crane is set up by the finite element software ANSYS and then the QTZ25 tower crane model is calculated.Through comparing the results,the feasibility of this method is proven.This method is a new approach to fast and precise analysis on dynamical model of tower crane structure.     

THE SOLUTION OF LOAD TIME FUNCTION IN INPUT EXCITATION OF DYNAMIC-STATE RESPONES OF A TOWER CRANE

According to the proporties of mechanisms in different working orders,this pa-per provides the load-time function by dynamic view. The input excitation is useful for the study of tower crane dynamic-state,and true for selution of tower crane dynamic equation. The view andway in the paper have the meaning of theory and practice for other engineering machinery     

Applying hybrid dynamic substructure synthetic method to dynamic analysis for tower crane

This paper presents a dynamic hybrid substructure synthetic method for tower crane dynamic analysis. This method employs the transfer matrix method and the flexibility degree method respectively to formulate the vibration mathematical models of the tower body and tower top system substructures in the hoisting luffing plane. Based on the motion of the substructures in the interface and the dynamic harmonize condition, the frequency equations are established. Then the program is designed according to the mathematical models and firstly applied to the dynamic analysis of the QTZ63 tower crane in the construction site and the parameter identification of attached device and tower body. The test results show that the value calculated by the above method is quite approximate to the instrument measured value, which can meet the engineering requirements. Further study has found that , for the flexible long-distance attached tower crane, the method that introduces dynamic load coefficient for statics analysis of tower cranes is unprecise enough since there exist errors.This paper suggests to conduct site test and identification of the rigidity coefficient of attached device of the tower crane for the accident prevention of tower crane collapse by timely take measures.     

Structural Model and Cargo-handling Technology of the Quay with High Amplitude of Water Level in Lantsang

The background of a west communication science & technology project whose topic is structural model and cargo-handling technology of the quay with high amplitude of water level in Lantsang is introduced, and its main research content, research of key technology and main findings are introduced too. Three types of structural model and cargo-handling technology which can be applied perfectly in Lantsang are put forward. The structural models include beam and slab structure with pillar supported, box bridge crane structure and reinforced earth structure, the cargo-handling technologies include vertical fixed crane technology, bridge crane technology and movable simple crane technology. Some findings have been applied in the supporting engineering-Menglun harbor.     

The Influence of Beam Column Stiffness Ratio of Mine Shaft Tower to Shear Lag Effect

Making use of large finite element analysis software ANSYS, combine with the mine shaft tower actual frame tube structure project to model analysis, by means of concrete performance of mine shaft tower under the effect of horizontal load, come to a conclusion that beam column stiffness ratio has a great influence on shear lag effect. Then analyse the phenomenon of beam column stiffness ratio to shear lag effect, make a comparison on calculated results and simulation analysis results, to move an improved method. It has a great guiding significance for the mine shaft tower structural design.     

A New Way for Analyzing the Strength of Frame of Truck Crane

In this paper, the formulas calculating the stress of frame of truck crane are deduced according to the thin wall structure theory, the calculation program is compiled and used in calculating the stress of the truck frame. The calculated results are checked and complemented by structural analysis program with finite element SAP5, providing the theoretical and calculation basis for design and calculation of the frame.     

THE FUZZY OPTIMIZATION DESIGN OF BOX EXPANSION ARM OF CRANE TRUCK

In this paper the section sizes of box expansion arm of crane truck are optimized in order that the weight of the arm will be the lightest on conditions that strength, rigidity, stability and size constraints are satisfactory. The fuzzy factors which influence design and the fuzziness of constraint conditions are considered. The unsymmetry mode of fuzzy optimization is established and solved by the method of optimal level cut set. Examples show that the effect is notable.     

Transverse Seismic Design and Analysis of an H Type Bridge Tower Cable Stayed Bridge

According to our current bridge seismic design codes, the bridge tower is explicitly required to remain almost elastic even under the excitation of occasionally happened earthquake. To achieve this seismic performance objective, usually the steel ratios of tower base and strut are required to satisfy the static loading demand and increase by a large margin as well in most engineering practices which leads to engineering inefficiency as well as a rising seismic demand for the substructure. Therefore, the structural design parameters including the location, the stiffness and the constrain condition of the strut with respect to the tower column of H shape tower were studied to explore their effect on the transverse seismic responses of cable-stayed bridge tower, Moreover, the effect of yield intensity of the strut on the seismic responses of the tower column is also studied. The results show that the location and the stiffness of the strut have a slight effect on the seismic responses while the transverse seismic demands of the bridge tower decrease drastically when the constrain condition between the cross beam and the tower column changes.     

输电钢管塔空间KK型管板连接节点极限承载力

空间KK型管板连接节点作为输电钢管塔中最主要的节点型式,其安全性是整个塔架结构安全的重要保证。相比较于平面K型节点,在考虑实际结构中节点空间效应后的KK型节点的受力性能更为复杂。在平面K型管板节点的试验研究基础上,对两类空间KK型管板节点展开参数化分析,重点讨论了节点几何尺寸参数和主管轴压应力比等因素对节点极限承载力的影响变化规律。结合大量有限元参数分析所得计算结果,并综合考虑各种因素对节点极限承载力的影响,提出了空间KK型管板连接节点在主管管壁局部屈曲破坏模式下的极限承载力建议计算方法。     

OPTIMAL CONTROL ELIMINATING SWING FOR THE LIFTING CAPACITY

This paper discusses the model for lifting capacity of the crane and optimal con-trol of eliminating swing in lifting process. One half loop control method is presented, which is onlyto examine and measure the trolley speed for eleiminating swing.The fact shows this methOd is sim-ple and practicle for enginceering.     

9种鹤类DNA条形码的研究

为了研究9种鹤类的DNA条形码,采用DNA条形码鸟类通用引物扩增中国4种鹤类（22个个体）的线粒体细胞色素C氧化酶亚基I（COI）基因。从GenBank及BOLD Systems下载13条鹤类的COI基因序列,对35条COI序列进行分析,构建NJ树和MP树,探讨DNA条形码对鹤类的识别和鉴定。结果显示,丹顶鹤群体中,除D1和B18号个体外,均被归为同一类群;白鹤群体中,编号为AY567881的个体与黑鹤划为同一类群;其余鹤类的系统发育分析结果均与形态学分类结果相同。由于丹顶鹤样本均取自沈阳森林野生动物园,所以是同一物种或是近缘物种杂交的可能性最大;白鹤较大的种内差异则可能是地理位置或是其他原因。     

Structural Optimum of Main Tower- Frame of Mast Crane

Taking the Structural optimum of main metal frame of mast- crane as a sample,this paper discussed the method of Structural optimization of common middle & high flexibility metal tower- frame by dynamic programming.The method of dynamic programming applied to the structural optimum was deducted and the minimum weight design method of tower- frame was practiced The paper gave up the traditional interactive way of choosing type of material,combining with the concrete example,changed the data- table looking up into formula solution,shifting with one by one into directly sieving within selected types,artificially fixing up composed rods into automaticaliy arranging them through the way of maximum twist moment of inertia,thus,accelerate optimization and offered a short way for artificial structural analysis and calculation.     

Structural Design of the Multi_Purpose Building for the Public Security Bureau,Xin Xiang City Henan Province

This paper introduces the methods of reducing and controlling differential settlement by changing the length and load_bearing capacity of the piles,and other means,rather than setting settlement gaps between the main building and the podium structure.By using these methods,the size of differential settlement observed is only 1mm.Because of the building with a tower 45m high,the earthquake magnification factor is taken as 3 with considering whiplash effect.     

THE THERMAL CRACK IN MASONRY STRUCTURE AND ITS CONTROL DESIGNING

The horizontal, vertical or oblique thermal cracks widely present in a masonry structure are summarized in this paper. The reasons for these cracks are analyzed.On basis of these causes, different methods called" readjusting", "releasing" and "resisting" for short, can be taken respectively in structure design to eliminate the cracks.     

八地脚螺栓刚性塔座板的承载力

随着中国电网技术的发展,杆塔负荷越来越大,八地脚螺栓塔座板应用越趋普遍。但现有计算理论与实际情况不符,为了使八地脚螺栓塔座板的计算方法合理、可靠,通过试验对八地脚螺栓刚性塔座板承载力进行了研究,同时借助有限元对构件进行了参数化分析。结合经典力学理论、试验及有限元数据,提出了全新的计算方法,引入了等效计算宽度和有效力臂的概念,充分考虑了底板刚度,屈曲后强度和垫板对承载力的影响,对工程设计具有指导意义。     

刚性连体位置对非对称双塔连体结构动力可靠度的影响

考虑地震动的非平稳性,变化连体位置,对非对称双塔连体结构运用虚拟激励法进行非平稳随机激励下的动力可靠度研究。采用刚度退化的Bouc-Wen模型模拟塔楼各楼层的滞变特性,建立非线性化动力方程。运用混合精细积分法对每一时刻的响应进行求解,得到连体位置变化时非对称连体结构在非平稳随机激励下的时变方差。基于首次超越破坏准则与Markov假定,研究非平稳随机地震激励下连体结构的动力可靠度。运用上述理论,在8度罕遇地震作用下对某非对称双塔连体结构进行随机地震响应与动力可靠度分析。研究结果表明,地震作用下结构的层间位移响应呈现强烈的非平稳性,变化连体位置对连体结构的随机地震响应与动力可靠度将产生显著影响。     

ANALYSIS OF THE TIME HISTORY RESPONSE FOR LARGE STRUCTURE UNDER THE ACTION OF IMPULSIVE LOADING USING STEP-BY-STEP REDUCED DYNAMIC-STIFFNESS COMPOSITION METHOD

In this paper, a dynamic substructure method for analysing the transient response of the large structure is proposed. The method is based or, the combination of the reduced dynamic-stiffness composition method and the step-by-stop integration method. Its main feature is that the computational effort may be reduced significantly. Several examples are given to prove its reliability, effectiveness and accuracy.     

THE OPTIMAL DESIGN AND ENGINEERING APPLICATION OF DISTRIBUTION

This paper introduces the metod of optimal design of municipal water distribution,The main points are the theory,mathematical model,program frame figure and example in practice of the optimal method of hydraulics.The program is applicable to the design and calculation of the pipe network in a city. It gives a simple and convenient calculation method for multiple-scheme design and scheme cmparison of water supply system.