Applied Mechanics and Materials Vols. 193-194

Abstract: With the sustainable economic development, a new multi-layer frame-bent industrial building is developed in the southeastern of China, based on a traditional bent industrial building. In this kind of structure, a framework is used in the longitudinal direction, the precast prestressed double-T plates is used in the middle layer, and the precast prestressed saddle plates is used on the roof. At present,the research achievements for this new multi-layer frame-bent industrial building under the action of earthquake .are seldom at home and abroad. In order to analyze the damaged mechanism and destroyed process on the structure of a new multi-layer frame-bent under the action of earthquake, elastic-plastic analysis of the structure must be completed. In this paper, the seismic performance of this new multi-layer frame-bent industrial building is studied by pushover analysis. The result shows that in the zone of a seismic fortification intensity as 70, both the elastic story drift under the action of frequently occurred earthquake and the elastic-plastic story drift under the action of rarely occurred earthquake for this new multi-layer frame-bent industrial building meet the requirements for the regulations of PROC;the plastic hinges appear first in the second floor, then develop to the first floor until the structure is destroyed.

Abstract: In this energy saving and environment protection society, as a new kind of air conditioning system, the combined cooling ceiling (CC) and displacement ventilation (DV) system has been attracting more and more attention both at home and abroad. This paper has done experiments with different supply air temperature, various supply air velocity and changeable temperature of supply water by simulating to cool a small office in summer. Based on similarity theories, some suggestions are given for the numerical area of cooling parameters under some laboratory conditions. According to PMV, it is also presented in general guidance for indoor air quality and thermal comfort with CC/DV system.

Abstract: From all kinds of project management mode, the characteristics of the model change reason and the opting of our country, the construction of the existing metro management mode has summarized. Domestic existing metro construction management model is divided into four categories, and the various modes of in-depth analysis, analysis of subway construction management mode changes and the reasons for our subway construction management mode selection recommendations.To improve the management level of China's subway construction in order to provide a reference.

Abstract: A simple pseudo-dynamic method to predict the seismic rotational displacement of retaining wall is developed. The proposed method, which soil-structure interaction is considered, is a combination of the free-field seismic response of soil and pseudo-dynamic method. It is supposed that soil and structure is connected by a series of springs, the dynamic earth pressure is determined by the deformation of springs. So both active and passive conditions can be taken into account by means of different movement direction of retaining wall, no need to know whether active or passive earth pressure happens before analysis. A significant difference between this analysis and published method is that in the present analysis the time dependent process of earth pressure and displacement is obtained by iterative calculation. Although present analysis is limit to elastic state, comparisons with Mononobe-Okabe method show satisfactory agreement in the value of resultant forces acting on retaining wall. Moreover, it is revealed by numerical examples that the height of the resultant force from the base of the wall is underestimated by the Mononobe- Okabe method, this may cause unsafe factors. Furthermore, the effect of wide range of parameters like time, height of retaining wall, wall friction, horizontal and vertical seismic coefficients are taken into account to evaluate the seismic response of retaining wall. Apart from its intrinsic theoretical interest, the proposed analysis can be used for the assessment of the safety of retaining wall under seismic condition.

Abstract: Chinese historical experience of constructing buildings merits attention. As the main and typical kind of Chinese traditional residential building, the dwelling with courtyard is “cool in summer”. However, less research on the thermal performance of dwelling with courtyard has been available in public literature. In this paper, based on the systematic analysis on various related elements, the physical and mathematical model of the air temperature distribution is set up. It is proved by the fieldwork measurement and computer simulation that the shielding effect of the aisle, side house and the long-narrow structure are the main reasons for the low temperature in courtyard.

Abstract: Structural robustness as a property of structural systems has gained renewed following several recent failures, where the consequences were disproportionate to the initating image. There have been some methods developed towards quantifying robustness or vulnerability and achieving greater robustness in structures recently but they remain scattered. In this paper, basis for the development of measures to quantify structural robustness are formulated. Various approaches for quantifying robustness are distinguished into measures based on structural behaviors and structural attributes of systems. It is shown that measures based on structural behaviors often seem to be expressive but require complex calculation. Measures based on structural attributes are usually calculable while their expressiveness is not yet adequate. Different types of structure which have a tendency for different types of collapse can be described favorably by different measures of robustness.

Abstract: With the continuous development of building energy efficiency, Wall insulation technology has become a new energy-saving technology. This paper mainly to a residential building model as an example in hot summer and cold winter zone (as in hefei). The ECOTECT simulation software was used to analysis the indoor uncomfortable period in different thickness of the exterior insulation layer. The Indoor uncomfortable period include too hot indoor discomfort period, too cold indoor uncomfortable period and total (obtain too hot and too cold) indoor discomfort period. According to the simulation result to analysis the relation between insulation layer thickness and the three kinds of indoor uncomfortable period. We can draw the total (obtain too hot and too cold) indoor uncomfortable period was not lowering with the increase of the insulation layer thickness, so we can choose the thickness of insulation layer, according to the influence of the thickness of insulation layer to the uncomfortable period, then providing certain reference for selection the thickness of insulation layer of energy conservation of the building wall.

Abstract: Currently, small car quantity of residents in the our country city is raise year by year.The parking problem of in each city's living area is outstanding day by day. Aimming at the difficult problem of parking the car, The paper analysis the reason for producing it, probes the countermeasures and solutions to the parking problems in residential areas from two aspects of parking index and the way of parking facilities.

Abstract: According to the failure characteristics of reinforced concrete bridge columns and the need of performance based seismic design in bridge, reinforced concrete bridge column performance levels, which are categorized into fully operational, temporarily operational, reparably operational, life safe and near collapse levels are established. To relate bridge damage to socio-economic descriptions at the five designated performance levels, qualitative indices are established. Considering field investigations following a seismic event, quantitative indices for the same five designated performance levels are proposed. Based on the statistical data of 154 seismic performance tests of RC bridge columns with circular section subjected to flexural failure, drift ratio limit for the same five designated performance levels are put forward. It can be used to determine displacement of pier top in performance based seismic design.

Abstract: This work presents the development and implementation of a mathematical formulation for obtaining optimal sections of reinforced concrete columns subjected to uniaxial flexural compression. In order to minimize the cost of the reinforced concrete columns, the amount and diameters of the reinforcement bars and the dimensions of the columns cross sections were considered as discrete variables. The optimization was made by Harmony Search optimization method, a metaheuristic inspired by music performance. Initially, the economical cost of each material (concrete, steel and formwork) were considered, as usual in most optimization strategies. In the sequence, the lesser environmental cost was studied, by considering the Life Cicle Assessment (LCA) to determine the global warming potential. The results obtained led to a different configuration when the objective is a reduction in carbon dioxide (CO2) emissions, regarding the optimum economical cost.