Advanced Materials Research Vols. 374-377

Abstract: Reinforced concrete (R/C) bridge pier with hollow section may undergo strongly nonlinear responses when subjecting severe earthquakes. The pier may perform flexure-shear coupling behavior, especially for the thin wall of the hollow section. Some simulation models accounting flexure-axial coupled effects were proposed, however, few simulation model is proposed for R/C hollow section bridge piers mainly impacted by the flexure-shear coupling. In this paper a beam-column element accounting for flexure-shear effect is presented. The mathematical theory for this element is flexibility-based formulation, and the section constructed by fibers can be treated as any kind of bi-axial materials. The cyclic soften membrane model (CSMM) constitutive relationship for plane bi-axial R/C components is used in the determination of the nonlinear behavior. Two cyclic pushover experiments were carried on scaled hollow section piers. The results deduced from the numerical model is compared with the experiment result. This fiber-based model provides sufficient accuracy and computational efficiency. The model has been implemented into the finite element program, OpenSees. And further researches will focus on the flexure-shear induced damage and collapse for bridge structures.

Abstract: The article reviews the application of GIS technology to urban planning and the research progress on construction suitability evaluation. It points out that the present evaluation method invisibly weakens high eco-sensitivity areas and unsafe areas, and therefore the evaluation process can not objectively reflect the different angles of urban land use and its contradiction and unity. Thus, the article suggests strengthening the idea of giving priority to ecology and city safety through analyzing key sensitive factors and perfecting multi-factor superposition method. It explores a new idea for land suitability evaluation from three angles, that is, eco-sensitivity evaluation, construction suitability evaluation and city safety. An empirical study is conducted on the master planning of Hongya County Town.

Abstract: The assessment of the risk probability and risk consequence of existing long-span bridges has become a focus in both research and engineering applications. In this paper, a process to assess the risk consequence of existing long-span bridges is developed. The analytic hierarchy process was combined with the fuzzy synthesis. In accordance with the features of existing long-span bridges, risk consequences are classified and the model of the risk consequence is simulated. A bridge as the example is evaluated by this process and the results show that the risk consequence of the bridge is negligible. Combining the risk probability and risk consequence gives the comprehensive risk of this bridge is negligible.

Abstract: As buildings tend to become bigger, higher and more complex, types of fire outbreak have diversified these days. Accordingly, it has also become difficult to cope with fire outbreaks resulting in a higher risk of suffering loss. The purpose of this study is to provide basic data for securing reasonable egress plans and safety of egress by comparing egress regulations of countries including America (NFPA 101), British (Building Regulation-Approve document B), New Zealand(Building Regulation & Compliance document for New Zealand building code), Japan (Architecture Relationship Statute book) and Korea (Architecture Statute book).

Abstract: Climate change and energy efficiency are some of the most pressing issues facing China today. With its economic growth since the economic reforms in 1978 the government has struggled to contain environmental damage and social strife related to the economy’s rapid transformation. With the rapid growth in population and urbanization the demand for housings escalated and thus existing houses are under threat of being demolished to make way for new construction. However there was a strong debate that existing houses should be maintained and upgraded instead of demolishing for new development as improvements to energy and water efficiency of existing homes can significantly reduce greenhouse gas emissions and decrease utility bills. This paper aims at reviewing the importance of existing houses and their environmental significance in conservation as opposed to demolition. This paper presents and discusses the preliminary results for the first two stages of a research project undertaken at the University of Technology Sydney to investigate environmental performance of historic housings in Xiao He Zhi Jie in Hangzhou, China.

Abstract: Zhaohua is a historic town of Sichuan province in China. On May 12th, 2008, a devastating earthquake measuring 8 on Richter scale struck Wenchuan, Sichuan province. In the process of recovery, 9 damaged historic buildings were demolished, 26 historic buildings were regenerated with new materials and 22 new buildings constructed in historic district. The purpose of this report is to study the space change of historic district during the process of recovery, and then attempt to get some lessons from the change of traditional space. We conclude that the emergency management is necessary for the whole environment of the historic district, in order to preserve the traditional space in post-earthquake. In China, although some principles on the conservation of historic districts were in place prior to the earthquake, during the process of recovery the local government did not forcibly ask the people to restore every historic building with original materials, additionally there were no legal consequences. This led to some historic buildings being restored with new materials or demolished, even historic spaces were changed. In Zhaohua, although a conservation plan was in place, mainly this plan focused on the preservation of traditional space and did not include emergency management on how to control the historic space and what should be done during a disaster and post disaster.

Abstract: On the premise of maintaining certain vertical bearing capacity, the frame structure dissipates seismic energy by elastic-plastic deformation in elastic-plastic stage of earthquake action. Using lightweight concrete in structure not only can reduce the its dead weight, decrease the earthquake power; also meet the concrete strength, stiffness and elastic modulus requirements of important structure, so as to improve its energy dissipation capacity. This paper researched the effect of concrete materials, including or such as C60 high strength Lightweight concrete (HSLC), high strength concrete (HSC) and high strength Light weight aggregate concrete (HSLAC), on the seismic behavior of RC column under horizontal low cyclic loading, respectively and the match relationship between concrete and steel reinforcement cage was analyzed.

Abstract: This paper focuses on the methodology and dynamic system of New-town practice, which corresponds with the policy-oriented principle in Xi’an, and analyzes the relativity between the evolution of spatial structure and the influential factors such as the land usage, resources endowment, economic development, population growth, by studying the process of Xi’an Newtown construction over the past 20 years. Xi’an Newtown is attached to the main city area like a magnetic container, absorbing population either from urban or rural area. Furthermore, it is more like a huge magnetic field composed with multiple small poles. To some extent, New-town practice in Xi’an follows the policy-oriented principle, and meanwhile meets the goal of regeneration of cultural heritages, ecological restoration and low-carbon control. Yet it is very different from the experiences of building an anti-magnetic system of metropolitans in European countries after the World War II. Till now, seven relatively independent "edge cities" have came into being with new cluster centers and edge-economic growth poles, which effectively keeps the suburbs from spreading disorderly.

Abstract: Abstract: A vibration analysis of light flexible steel footbridge is investigates in this paper, which is based on dynamic testing. The finite element model of the footbridge was established. In this paper the reason is also analyzes which causes the vibration characteristic from the ambient excitation and its own structural features. Key words: Footbridge; Vibration Analysis; Dynamic Testing; Modal Analysis; Ambient Excitation;

Abstract: When the power transmission line is covered with ice and snow in the winter, the galloping of power line often happens. A new type of damper used for preventing galloping of the electric power transmission line has been put forward and received patent license of China. The damper like fan blades, which can rotate about the axes of the power line at 360°, is fixed on the overhead power line. It hangs on the line when there is no wind. The blade rotates at high speed in the plane vertical to wind when there is wind, which results in a gyroscope. The theorem of angular momentum of a gyroscope is used in the design of the damper. Model tests of this kind of damper have been carried out and the results show that it is successful in preventing galloping of the cable model.