Mechanical Performance of a Vertical Seismic Isolation System Employing a Dish Spring

The base isolation technique has been widely used in different countries to reduce seismic disasters during earthquakes. But most of these devices are effective only in horizontal earthquake responses and do not work well in vertical earthquake responses. We propose a vertical seismic isolation system composed of a dish spring and a visco-elastic damper. To study the stiffness and damping performance of this isolation system, a series of tests under static and dynamic loads were performed. The results show that this system is effective in solving problems related to strong vertical bearing capacity and vertical damping of vertical isolation. The system has not only appropriate vertical stiffness and damper performance, but also excellent mechanical performance. In addition, it is compact, easy to manufacture, and can serve as an ideal vertical damping device.     

Piezoelectric Control of Lifting Surface Flutter

Piezoelectric material was used to establish a single input/single output (SISO) model of a lifting surface with distributed piezoelectric actuators and piezoelectric sensors. The flutter equations and state space equations of piezoelectric laminated structures were also derived. MATLAB, NASTRAN and other software programs compiled by the authors also were used to analyze the flutter and dynamic characteristics. The stability of the closed loop was analyzed for the SISO. The result indicates that the control law can be employed for flutter suppression.     

Civil Servant House Subsidy Schemes of the Chinese Central Government

Based on a theoretical analysis of supply- and demand-side subsidies, the current housing subsidy schemes and practices of Chinese Central Government Departments were summarized. A discrete choice model was adopted to analyze the interrelationship between the housing subsidy choices of civil servants and impact factors. Several policy recommendations are offered for government to improve the efficiency of civil servant housing subsidy policies.     

Effects of Stone Powder on Wet Packing Density of Cement and Performances of Concrete

The amount of limestone powder, which is a by product of manufactured fine aggregate, is larger and larger with the increase of manufactured fine aggregate. Environment will be severely polluted if the powder is improperly used. The effects of limestone powder on workability, compressive strength, and impermeability of concrete were studied when cement is substituted for the mass proportion of 0, 10, 15, 20 percent with it. The results show that the performances of concrete are better improved when the percentage of limestone powder is about 10 percent. The wet packing density of mixture of limestone powder and cement was measured, and it shows that the degree of density was biggest when limestone powder is 10 percent. This shows that the best mixing proportion of limestone powder and cement may be determined through measuring the change of compactness of mixture of limestone powder and cement.     

Environmental Impact Modeling of Urban Sprawl in Beijing, P. R. China

City expansion is a major driving force altering local and regional hydrology and increasing non point source (NPS) pollution. To explore these environmental consequences of urbanization, long term runoff and NPS pollution were assessed in Beijing, P. R. China. The assessment was based on land use types, soil hydrology, and long term precipitation data. The environmental impact model L THIA was used. The outcomes indicate that the area likely would be subjected to impacts from urbanization on runoff and some types of NPS pollution. Urban sprawl will increase runoff volume considerably and significantly increase losses of COD and certain heavy metals such as Pb, Zn in runoff. The results of this study have significant implications for urban planning and decision making efforts to protect and remediate water and habitat quality in the Beijing area. The techniques described herein can be used in other areas.     

A Type of Architectural Esthetics with Publicizing Vitality: Understanding the Qiang Community in Taoping

The life style, military defense and religious belief of the Qiang people combined with the local natural environment created a special architectural esthetic found in the upper reaches of the Minjiang River in P. R. China. The esthetics of this Qiang community are expressed clearly in the harmonious mountainous settlement, and plain housing shape. We expound on their characteristic watchtower construction. The esthetic significance and value of this Qiang community lies in unfolding the great strength of tragic art. We further elaborate on the commendable innovative spirit formed in the difficult times faced by the Qiang natconality. Their landscapes also manifest the highest level of architectural esthetics that regional architecture has achieved.     

Energy Consumption Features for Large scale Public Office Buildings in Greater Guangzhou, P. R. China

The annual energy consumption of representative office buildings in Guangzhou, P. R. China, was surveyed over a three year period. Among the modern office buildings surveyed, two large scale office buildings were chosen to analyze the energy consumption features and monthly energy consumption trends. Based on the actual occupied area calculation, the total annual energy consumption of the two office buildings was 149.3 kWh/m2 and 115 kWh/m2, respectively. The air conditioning energy consumption in two office buildings accounted for 49.2% and 38.5% of the total energy consumption. The research results could be used as energy consumption sub databases or references for large scale public buildings in Guangzhou due to the accurate survey technique and representativeness of the survey objects. In addition, energy consumption in these office buildings was compared with levels described in other studies. Energy saving methods are proposed for buildings located in hot summer/warm winter climate zones.     

A 3D Visco elasto plastic Finite Element Analysis of the Asphalt Pavement Rutting Deformation

Based on the dynamic action between vehicles and pavement, a simplified model of vehicle dynamic loading caused by surface evenness was established. This research made it possible to find a Asphalt Pavement Rutting Prediction method based on the theory of visco elasto plasticity which is the basic theory of the dynamics, and finite element method (FEM). Asphalt pavement rutting was calculated and predicted, and the factors influencing rutting were analyzed and calculated. The good agreement between the calculation results and the testing road data indicate that the rutting prediction method is reasonable and reliable.     

Research on Preparation of Non-Autoclaved Aerated Concrete with Phosphorus Slag

In order to prepare aerated concrete with alkali-phosphorus slag and better use of industrial waste, the powder composition of the slurry was investigated. The impacts of certain factors on aerated concrete, including the foaming agent, sodium silicate modulus, alkali content and the temperature of alkali solution also were investigated using single-factor test methods. The results indicate that: the cement and fly ash in powder have impacts on the pouring stability of slurry, and the bulk density of aerated concrete is impacted by the amount of foaming agent, sodium silicate modulus and alkali content. In the experiment, aerated concrete with bulk density in range of 535~887 kg/m3 and compressive strength of 6~9.5 MPa was produced; its mechanical performance conforms to the requirements of the standard GB 11968 2006.     

Early Warning of Risk for Transportation Infrastructure Projects under a PPP Model

Based on characteristics of transportation infrastructure projects under a PPP model, an early warning risk index system for the private sector was put forward. The system is comprised of 15 indexes from five aspects, including risks associated with politics and law, economics, credit, construction and operation. An early warning risk model was constructed by applying fuzzy set theory and matter element theory. The fuzzy set method helps calculate the weight and evaluation values for qualitative indexes, thereby avoiding the limitations of individual decisions. The matter element method can evaluate comprehensive risks by using the comprehensive relations, is easy to use, and directly gives results. Further empirical research was conducted that verifies this method is scientific and applicable.