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Based on the Loves shell theory, relationship between bending solutions of functionally graded materials (FGM) and homogenous circular cylindrical shells was studied. By comparing the displacement-type governing equations for axially symmetrically bending of FGM and homogenous circular cylindrical shells, an analogous transform relation between the deflections of FGM circular cylindrical shell and those of homogenous one was obtained. By giving the material properties of FGM circular cylindrical shell changing as continuous functions in the thickness direction, the corresponding transition factor between the solutions of the two kind circular cylindrical shells were derived, which reflect the non-uniform properties of the functionally graded material circular cylindrical shell. Numerical example shows that the numerical solutions of the maximum of non-dimensional deflections are almost in agreement with the transformational solutions whennequals approximately 5, wherenis the volume fraction index. As a result, solutions for axially symmetrically bending of a non-homogenous circular cylindrical shell can be reduced to that of a homogenous one and the calculation of the transformation factors.

Based on the accurate geometrical theory for the extensible elastic beams, an exact mathematical model of post-buckling transverse free vibration of Euler beams subjected to a distributed tangential follower force along the central axis are established. By using shooting method, pre-buckling free vibrations of both simply supported and fixed Euler beam are solved and the responses of small amplitude vibration are obtained. The numerical results show that all the frequencies of unbuckled beams decrease continuously with the increment of the load parameters.

Coal spontaneous combustion is a complex procedure of physical and chemical changing, in which the macro characters is the reflection of micro changes of coal molecule structure in low temperature oxidation. In order to understand the essence of coal-oxygen composition, the Fourier transform infrared spectrum apparatus is used to test and analyze different kinds of coal samples in different oxidation temperature. According to main characteristic spectrum peaks, the activity of coal functional groups is studied. The difference and change of the type and quantity of functional groups in different kinds of coal sample in different temperature are analyzed. The relation between the macro structure change and spontaneous combustion property of coal in low temperature oxidation process is discussed.

Relationship between bending solutions of functionally graded Timoshenko beams (FGMTB) and those of homogenous Euler-Bernoulli beams (HEBB) were studied in this presentation. The deflection and the rotational angle of FGMTB are expressed in terms of the deflection of the corresponding HEBB with the same geometry, loadings and end constraints. Consequently, solutions of bending of the FGMTB are simplified as the calculation of the transition coefficients which can be easily determined by the variation law of the gradient of the material properties and the geometry of the beams because the solutions of corresponding HEBB are well known. As examples, solutions for the FGM Timoshenko beams under S-S, C-C, C-F and C-S end constraints and subjected to arbitrary transverse loadings were presented. These analytical solutions can be as benchmarks in the further investigations of behaviors of FGM beams.

Project stakeholders play an important role in the implementation process of sustainable construction. Due to different attributes of each stakeholder in the project, their importance level is different. This paper firstly identifies 13 project stakeholders based on Chinese construction project management mechanism and then a questionnaire survey was conducted to investigate their importance. This finding indicates that client and government play extremely important role in the sustainable construction; all the project stakeholders are important in the three aspects and the importance level order of project stakeholders in the three aspects is different.

The size, the position and the arrangement of external restraint will significantly affect the mechanical properties of the structures with the external restraint. Based on classical beam theory, the stress distribution of a simply supported beam with externally reinforcing steel bars under transverse loads is analyzed in this presentation. By assuming that the stresses in both the beam and the external constrains are less than their proportional limits, an analytical formulation of normal stress in the cross section of the beam was derived by considering two cases that the externally reinforcing steel bars are pre-stressed and are not pre-stressed. Influences of the parameters of the stiffness and the position of the externally reinforcing steel bars on the stress of the beam are discussed.

Architecture is one of the most element of urban composition.During urban renewal, how to follow the characteristics of mountain, how to respect for history and local culture, how to continue and inherit historical context of architecture is the purpose of this article.The article puts forward some measures of continuing and inheriting historical context of architecture from planning, creating of mountainous architecture, protecting and managing,etc.

Because of large flexibility and strong geometric nonlinearrity, the time domain method should be applied in the analysis of wind-induced vibration for the membrane structure, and the coupling effect between the structure and the fluid should also be considered. In this problem, it is hard now to solve it directly using the technique of three-dimensional transient FSI based on CFD. So in the article, a compromise schedule is proposed, i.e, for the mean wind part, the steady-state FSI technique is applied to solve the parameter such as the mean pressure coefficient, the mean wind velocity, etc, while for the fluctuating wind part, the time integral method is used based on the stochastic function of the wind velocity formed by auto regressive method. The aerodynamic damping is considered in the solving of fluctuating part and five computing schedule are compared, result shows that it is better to use positive mean wind damping for the nodes. It is also suggested that the stochastic wind velocity functuion can be revised based on the kinetic energy distribution of the reference points. A comparison between the computing and testing results show that it is greatly improved for the fluctuating response distribution of the structure.

Based on the generalized coupled thermoelasticity in the Lord-Shulman (L-S) model, the state equation of infinite functionally graded plates were established by using of the Laplace transform and state space approach, in which the displacement, temperature and their first derivatives were chosen as state variables. As a numerical example, a functionally graded plate with the material properties changing by exponential law distribution along the thickness of plate, subjected to thermo-mechanical shock was considered. By employing the numerical inversion of the Laplace transform, numerical result showing the temperature, the displacement and stress components changing with the time are represented graphically. Characteristics of the propagation of the thermal elastic wave are also analyzed.

Based on discrete element method, the mechanical responses of a functionally graded cantilever beam are studied by using of two kinds of particle with different properties. The variation of material properties along the thickness direction is simulated by the different distribution of constituent particles in space. The method validity was tested, and the influence of material homogenous on deformation and stiffness of cantilever beam under mechanical load were studied make use of numerical examples. Method in this paper will provide a new way for analyzing of functionally graded materials and its optimizing design from micromechanism.

Cost controlling is key behavior of getting more profits in an enterprise, but the cost of construction material cover 40-60 percent or more. So, reduce its cost as less possible as on the premise of insuring material quality is very important. The article starts from this, and gives some suggestions about controlling of the cost of construction material.