腹有诗书气自华

吉尔勃特讥讽人类不过是剃净了毛的猴子。史密斯则根据人会著书这一条反驳了他的论点。是的，猴子只会吵吵闹闹，而人类将书籍充满这个世界。可是，人也并非个个相同，我在吉辛的《四季随笔》中看到过一段话：在读过书和没有读过书的人之间，同死人与活人之间，有同样大的差别。

学法用法 积极纳税──记阜南县草鞋工艺有限公司经理阚同法

学法用法 积极纳税──记阜南县草鞋工艺有限公司经理阚同法张亚林，陈飞，王广乾阚同法，一位具有开拓精神的青年，去年年底自筹资金２０多万元，创办了阜南县草鞋工艺有限公司。由于他善于捕捉市场信息，经营有方，创建公司仅几个月时间就取得了可观的经营收入，上交税...

硬道理的威力──山东临沂市丝绸抽纱（工贸）集团公司发展侧记

硬道理的威力──山东临沂市丝绸抽纱（工贸）集团公司发展侧记王茂全，张京森发展才是硬道理这句话，对于临沂市丝绸抽纱（工贸）公司的领导来说，有着特别深切的体会。没有发展，从宏观来说我国就不能建设有中国特色的社会主义，从微观来说企业就不能在激烈竞争的市场经...

Wind Vibration Study of Long-span Steel Arch Structure of Beijing Capital International Airport

The wind-induced dynamic response of long-span light-weight steel arch structure of the global transportation center (GTC) of Beijing Capital International Airport was studied. A composite technique with combination of WAWS(Weighted Amplitude Wavelet Superposition) and FFT(Fast Fourier Transformation) was introduced to simulate wind velocity time series of hundreds of spatial points simultaneously. The structural shape factors of wind load was obtained from wind tunnel model test. The wind vibration factor based on structural displacement response was investigated. After comparing the computational results with wind tunnel model test data, it was found out that the two results accord with each other if wind comes from 0° direction angle, but are quite different if wind comes from 180° direction angle in the area blocked off by airport terminals. The possible reasons of this difference were analyzed. Haar wavelet was used to transform and analyze wind velocity time series and structural wind-induced dynamic responses. The relationship between exciting wind loads and structural responses was studied in time and frequency domains.

Preliminary analysis of mode truncation of single-layered reticulated domes under earthquakes

In anti-seismic calculation, the mode truncation is a significant problem to engineers if the mode-superposition response spectrum method is used, which has not been completely solved yet in some large and complex structures such as reticulated domes. In this case, some useful advices, concentrating on the problem above, are expected through a careful and comprehensive investigation of this paper. During the investigation, the authors first point out shortcomings of former researches. Then frequency-spectrum characteristics of single-layered reticulated domes were studied from the perspective of structural responses. During this process, some important results such as the existence of the main resonant section, and the fact that the relative sensitivity of these domes under horizontal and vertical impulse varies with the different R/S ratios were achieved. Furthermore, based on the study of frequency-spectrum characteristics, as well as that of earthquake input, reasonable numbers of mode truncation in single layered reticulated domes with different R/S ratio were presented. Results of case studies prove the mode truncation number proposed is valid.

Fatigue behaviour of welded joints assembled by longitudinal corrugated plates

Fatigue is usually the cause for the cracks identified at bridge elements in service. With an increase in the introduction of corrugated steel web girders in recent highway bridge construction, the understanding of the fatigue behaviour of welded details in such structures becomes an important issue for the design. The typical welded details were represented as welded joints assembled by longitudinal corrugated plates. All the experiments were performed under fatigue loading using a servo-control testing machine. The test results from the failure mode observation with the aid of infrared thermo-graph technology show that the failure manner of these welded joints is comparable to that of the corrugated steel web beams reported previously. It is indicated from the stiffness degradation analysis that the welded joints with larger corrugation angle have higher stiffness and greater stiffness degradation in the notable stiffness degradation range. It is shown from the test S-N relations based on the free regression and forced regression analyses that there is a good linear dependence between lg(N) and lg(ΔS). It is also demonstrated that the proposed fracture mechanics analytical model is able to give a prediction slightly lower but on the safe side for the mean stresses at 2 million cycles of the test welded joints.

Analysis of raft foundation design based on considering influence of superstructure stiffness

The finite element method was used for analysis of raft foundation design in high-rise building.Compared with other conventional methods,this method is more adapted to the practical condition since both superstructure stiffness and soil conditions were considered in calculation.The calculation results by example show that the base reaction is more uniform and the maximum reaction decreases obviously.Accordingly,the raft foundation design is more economic without any loss of security for high-rise building.

Research on the Multidimensional Constraint Stability of Bridge Structure Modeling based on Optimization Model

In this paper, we conduct research on the multidimensional constraint stability of bridge structure modeling based on the optimization model. The current internal and the external research results to the truss web structure, the high internode the aspect ratio and the stiffness of the middle truss brace of the truss web, deffection of composite beams of the impact of stress is a very important problem in the design of the bridge. Structural health monitoring is the use of the field of the non-destructive sensing technology, including the structural response, including structural system characteristics analysis, to achieve the purpose of monitoring structural damage or degradation. Under this basis, this paper proposes the new idea on the modelling and simulates the performance.

Non-linear Aerothermoelastic Modeling and Behavior of a Double-wedge Lifting Surface

The design of the re-entry space vehicles and high-speed aircraft structures requires special attention to the non-linear thermoelastic and aerodynamic instabilities.The thermal effects are important since temperature environment influences significantly the static and dynamic behaviors of flight structures in supersonic/hypersonic regimes.The dynamic behavior of a double-wedge lifting surface with combined freeplay and cubic stiffening structural nonlinearities in both plunging and pitching degrees-of-freedom(DOF) operating in supersonic/hypersonic flight speed regimes has been analyzed.In addition a third order piston theory aerodynamics(PTA) is used to evaluate the non-linear unsteady aerodynamic loads applied to the wing section.Loss of torsional stiffness that may be incurred by lifting surfaces subjected to axial stresses induced by aerodynamic heating is also considered.The aerodynamic heating effect is estimated based on the adiabatic wall temperature due to high speed airstreams.It is demonstrated that serious losses of torsional stiffness may occur in such lifting surfaces;the influence of various parameters such as flight condition,thickness ratio,freeplays and pitching stiffness nonlinearity are discussed.

Mathematical modeling and numerical simulation of telephone cord buckles of elastic films

An annular sector model for the telephone cord buckles of elastic thin films on rigid substrates is established, in which the von Krman plate equations in polar coordinates are used for the elastic thin film and a discrete version of the Griffith criterion is applied to determine the shape and scale of the parameters. A numerical algorithm combining the Newmark-β scheme and the Chebyshev collocation method is designed to numerically solve the problem in a quasi-dynamic process. Numerical results are presented to show that the numerical method works well and the model agrees well with physical observations, especially successfully simulated for the first time the telephone cord buckles with two humps along the ridge of each section of a buckle.