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High-rise Buildings (high-rise + building)
Selected AbstractsNeue Erkenntnisse zum Verformungsverhalten des Frankfurter TonsBAUTECHNIK, Issue 3 2007Rudolf Dürrwang Dipl.-Ing. Anhand des Bauvorhabens "Opernturm" von Tishman Speyer auf dem ehemaligen Gelände der Zürichversicherung "Zürichhaus" an der Alten Oper im Zentrum von Frankfurt am Main wird dargestellt, daß der Effekt der Entlastung/Wiederbelastung ausschließlich zeitabhängig ist. Dies wurde möglich, da erstmals in Frankfurt nach dem Abbruch der alten Zürichhäuser sechs Jahre vergingen, bis mit dem Neubau begonnen wurde. In diesem Zeitraum wurden die Hebungen der alten Gründung (Bestandskeller) und der Nachbarn (u.a. U-Bahn) als Teil des Beweissicherungsverfahrens beobachtet. Weiterhin werden die Ergebnisse von Cross-hole-Messungen zur Bestimmung der dynamischen Baugrundsteifigkeit des Frankfurter Baugrunds dargestellt und diskutiert. New knowledge about the deformation behaviour of Frankfurt clay und unloading conditions. Tishman and Speyer planed the construction of a new building complex "Opernturm" in the down town of Frankfurt, Germany. The construction of the new High-Rise building required the demolishing of the old two high rise buildings of the Zurich insurance company. After demolishing the old high rise buildings, a time delay of about 6years has occurred. The deformations of the rest basement of the old buildings as well as the deformation of Neighbouring construction such as the underground tunnel were observed with time as a part of validating the serviceability requirements of the neighbouring constructions. The results of these measurements regarding the time effect on the behaviour of Frankfurt overconsolidated clay under unloading conditions will be presented. Furthermore, the results of cross hole tests that were carried out as a part of the design of the suggested piled raft foundation of the new high rise building to investigate the dynamic behaviour of Frankfurt subsoil will be demonstrated and discussed. [source] VIOLENCE AMONG ADOLESCENTS LIVING IN PUBLIC HOUSING: A TWO-SITE ANALYSIS,CRIMINOLOGY AND PUBLIC POLICY, Issue 1 2003TIMOTHY O. IRELAND Research Summary: Current knowledge about violence among public housing residents is extremely limited. Much of what we know about violence in and around public housing is derived from analysis of Uniform Crime Report (UCR) data or victimization surveys of public housing residents. The results of these studies suggest that fear of crime among public housing residents is high and that violent offense rates may be higher in areas that contain public housing compared with similar areas without public housing. Yet, "[r]ecorded crime rates (and victimization rates) are an index not of the rate of participation in crime by residents of an area, but of the rate of crime (or victimization) that occurs in an area whether committed by residents or non-residents" (Weatherburn et al., 1999:259). Therefore, neither UCR nor victimization data measurement strategies address whether crime in and around public housing emanates from those who reside in public housing. Additionally, much of this research focuses on atypical public housing,large developments with high-rise buildings located in major metropolitan areas. To complement the existing literature, we compare rates of self-reported crime and violence among adolescents who reside in public housing in Rochester, N.Y., and Pittsburgh, Pa., with adolescents from the same cities who do not live in public housing. In Rochester, property crime and violence participation rates during adolescence and early adulthood among those in public housing are statistically equivalent to participation rates among those not in public housing. In Pittsburgh, living in public housing during late adolescence and early adulthood, particularly in large housing developments,increases the risk for violent offending, but not for property offending. The current study relies on a relatively small number of subjects in public housing at any single point in time and is based on cross-sectional analyses. Even so, there are several important policy implications that can be derived from this study, given that it moves down a path heretofore largely unexplored. Policy Implications: If replicated, our findings indicate that not all public housing is inhabited disproportionately by those involved in crime; that to develop appropriate responses, it is essential to discover if the perpetrators of violence are residents or trespassers; that policy should target reducing violence specifically and not crime in general; that a modification to housing allocation policies that limits, to the extent possible, placing families with children in late adolescence into large developments might reduce violence perpetrated by residents; that limited resources directed at reducing violence among residents should be targeted at those developments or buildings that actually have high rates of participation in violence among the residents; and that best practices may be derived from developments where violence is not a problem. [source] A substructure shaking table test for reproduction of earthquake responses of high-rise buildingsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2009Xiaodong Ji Abstract When subjected to long-period ground motions, high-rise buildings' upper floors undergo large responses. Furniture and nonstructural components are susceptible to significant damage in such events. This paper proposes a full-scale substructure shaking table test to reproduce large floor responses of high-rise buildings. The response at the top floor of a virtual 30-story building model subjected to a synthesized long-period ground motion is taken as a target wave for reproduction. Since a shaking table has difficulties in directly reproducing such large responses due to various capacity limitations, a rubber-and-mass system is proposed to amplify the table motion. To achieve an accurate reproduction of the floor responses, a control algorithm called the open-loop inverse dynamics compensation via simulation (IDCS) algorithm is used to generate a special input wave for the shaking table. To implement the IDCS algorithm, the model matching method and the H, method are adopted to construct the controller. A numerical example is presented to illustrate the open-loop IDCS algorithm and compare the performance of different methods of controller design. A series of full-scale substructure shaking table tests are conducted in E-Defense to verify the effectiveness of the proposed method and examine the seismic behavior of furniture. The test results demonstrate that the rubber-and-mass system is capable of amplifying the table motion by a factor of about 3.5 for the maximum velocity and displacement, and the substructure shaking table test can reproduce the large floor responses for a few minutes. Copyright © 2009 John Wiley & Sons, Ltd. [source] Seismic microzonation of the greater Bangkok area using microtremor observationsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 2 2004Rabin Tuladhar Abstract Bangkok, the capital city of Thailand, is located at a remote distance from seismic sources. However, it has a substantial risk from these distant earthquakes due to the ability of the underlying soft clay to amplify ground motions. It is therefore imperative to conduct a detailed seismic hazard assessment of the area. Seismic microzonation of big cities, like Bangkok, provides a basis for site-specific hazard analysis, which can assist in systematic earthquake mitigation programs. In this study, a seismic microzonation map for the greater Bangkok area is constructed using microtremor observations. Microtremor observations were carried out at more than 150 sites in the greater Bangkok area. The predominant periods of the ground were determined from the horizontal-to-vertical (H/V) spectral ratio technique. A microzonation map was then developed for the greater Bangkok area based on the observations. Moreover, the transfer functions were calculated for the soil profile at eight sites, using the computer program SHAKE91, to validate the results from the microtremor analysis. The areas near the Gulf of Thailand, underlaid by a thick soft clay layer, were found to have long natural periods ranging from 0.8s to 1.2s. However, the areas outside the lower central plain have shorter predominant periods of less than 0.4s. The study shows that there is a great possibility of long-period ground vibration in Bangkok, especially in the areas near the Gulf of Thailand. This may have severe effects on long-period structures, such as high-rise buildings and long-span bridges. Copyright © 2003 John Wiley & Sons, Ltd. [source] Prediction of the maximum credible ground motion in Singapore due to a great Sumatran subduction earthquake: the worst-case scenarioEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 8 2002Kusnowidjaja Megawati Abstract Although Singapore is located in a low-seismicity region, huge but infrequent Sumatran subduction earthquakes might pose structural problems to medium- and high-rise buildings in the city. Based on a series of ground motion simulations of potential earthquakes that may affect Singapore, the 1833 Sumatran subduction earthquake (Mw=9.0) has been identified to be the worst-case scenario earthquake. Bedrock motions in Singapore due to the hypothesized earthquake are simulated using an extended reflectivity method, taking into account uncertainties in source rupture process. Random rupture models, considering the uncertainties in rupture directivity, slip distribution, presence of asperities, rupture velocity and dislocation rise time, are made based on a range of seismologically possible models. The simulated bedrock motions have a very long duration of about 250 s with a predominant period between 1.8 and 2.5 s, which coincides with the natural periods of medium- and high-rise buildings widely found in Singapore. The 90-percentile horizontal peak ground acceleration is estimated to be 33 gal and the 90-percentile horizontal spectral acceleration with 5% damping ratio is 100 gal within the predominant period range. The 90-percentile bedrock motion would generate base shear force higher than that required by the current design code, where seismic design has yet to be considered. This has not taken into account effects of local soil response that might further amplify the bedrock motion. Copyright © 2002 John Wiley & Sons, Ltd. [source] The Space of Local Control in the Devolution of us Public Housing PolicyGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 4 2000Janet L. Smith Sweeping changes in national policy aim to radically transform public housing in the United States. The goal is to reduce social isolation and increase opportunities for low income tenants by demolishing ,worst case' housing, most of which is modern, high-rise buildings with high vacancy and crime rates, and replacing it with ,mixed-income' developments and tenant based assistance to disperse current public housing families. Transformation relies on the national government devolving more decision-making power to local government and public housing authorities. The assumption here is that decentralizing the responsibility for public housing will yield more effective results and be more efficient. This paper explores the problematic nature of decentralization as it has been conceptualized in policy discourse, focusing on the underlying assumptions about the benefits of increasing local control in the implementation of national policy. As this paper describes, this conceived space of local control does not take into account the spatial features that have historically shaped where and how low income families live in the US, including racism and classism and a general aversion by the market to produce affordable rental units and mixed-income developments. As a result, this conceived space of local control places the burden on low income residents to make transformation a success. To make this case, Wittgenstein's (1958) post-structural view of language is combined with Lefebvre's view of space to provide a framework in which to examine US housing policy discourse as a ,space producing' activity. The Chicago Housing Authority's Plan for Transformation is used to illustrate how local efforts to transform public housing reproduce a functional space for local control that is incapable of generating many of the proposed benefits of decentralization for public housing tenants. [source] Application of a Service Climbing Robot with Motion Planning and Visual SensingJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 4 2003Jian Zhu This paper describes an application of a service climbing robot aimed to clean the glass wall of high-rise buildings. The robot utilizes suction cups to adhere to the glass and moves with a translational mechanism to follow a predetermined path in cleaning the whole glass surface. By a flexible waist, the robot can adjust its posture. The robot has the ability to cross the window frame to clean different sections of the glass wall. A visual sensing system, composed of an omnidirectional CCD camera and two laser diodes, enables the robot to measure its orientation and the distance between the robot and the window frame. The real-time applications and some experimental results demonstrate the effectiveness of the developed system. © 2003 Wiley Periodicals, Inc. [source] Modelling the impact of high-rise buildings in urban areas on precipitation initiationMETEOROLOGICAL APPLICATIONS, Issue 2 2007M. G. D. Carraça Abstract The impact of urban areas upon precipitation distribution has been studied for many years. However, the relative importance of the distribution and type of surface morphology and urban heating remains unclear. A simple model of the surface sensible heat flux is used to explore the impact of urban heterogeneity. Sensitivity experiments are carried out to test the validity of the model, and experiments with a schematic urban morphology are used to investigate the impact of different types of building arrays. It is found that high-rise buildings over relatively small areas may have just as much impact as somewhat lower buildings covering a much larger area. The urban area produces considerable spatial variation in surface sensible heat flux. Data from a C-band radar located to the north of Greater Manchester provides evidence that convective cells may be initiated by the sensible heat flux input generated by the high-rise buildings in the city centre when the atmospheric boundary layer is unstable. Copyright © 2007 Royal Meteorological Society [source] The impact of urban areas on weatherTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 614 2006C. G. Collier Abstract The industrial revolution led to a rapid development of urban areas. This has continued unremittingly over the last 200 years or so. In most urban areas the surface properties are heterogeneous, which has significant implications for energy budgets, water budgets and weather phenomena within the part of the earth's atmosphere that humans live. In this paper I discuss the structure of the planetary boundary layer, confining our analysis to the region above the rooftops (canopy layer) up to around the level where clouds form. It is in this part of the atmosphere that most of the weather impacting our lives occurs, and where the buildings of our cities impact the weather. In this review, observations of the structure of the urban atmospheric boundary layer are discussed. In particular the use of Doppler lidar provides measurements above the canopy layer. The impact of high-rise buildings is considered. Urban morphology impacts energy fluxes and airflow leading to phenomena such as the urban heat island and convective rainfall initiation. I discuss in situ surface-based remote sensing and satellite measurements of these effects. Measurements have been used with simple and complex numerical models to understand the complexity and balance of the interactions involved. Cities have been found to be sometimes up to 10 degC warmer than the surrounding rural areas, and to cause large increases in rainfall amounts. However, there are situations in which urban aerosol may suppress precipitation. Although much progress has been made in understanding these impacts, our knowledge remains incomplete. These limitations are identified. As city living becomes even more the norm for large numbers of people, it is imperative that we ensure that urban effects on the weather are included in development plans for the built environment of the future. Copyright © 2006 Royal Meteorological Society [source] The "Vertical Response Time": Barriers to Ambulance Response in an Urban AreaACADEMIC EMERGENCY MEDICINE, Issue 9 2007Robert A. Silverman MD Background: Ambulance response time is typically reported as the time interval from call dispatch to arrival on-scene. However, the often unmeasured "vertical response time" from arrival on-scene to arrival at the patient's side may be substantial, particularly in urban areas with high-rise buildings or other barriers to access. Objectives: To measure the time interval from arrival on-scene to the patient in a large metropolitan area and to identify barriers to emergency medical services arrival. Methods: This was a prospective observational study of response times for high-priority call types in the New York City 9-1-1 emergency medical services system. Research assistants riding with paramedics enrolled a convenience sample of calls between 2001 and 2003. Results: A total of 449 paramedic calls were included, with a median time from call dispatch to arrival on-scene of 5.2 minutes. The median on-scene to patient arrival interval was 2.1 minutes, leading to an actual response interval (dispatch to patient) of 7.6 minutes. The median on-scene to patient interval was 2.8 minutes for residential buildings, 2.7 minutes for office complexes, 1.3 minutes for private homes (less than four stories), and 0.5 minutes for outdoor calls. Overall, for all calls, the on-scene to patient interval accounted for 28% of the actual response interval. When an on-scene escort provided assistance in locating and reaching the patient, the on-scene to patient interval decreased from 2.3 to 1.9 minutes. The total dispatch to patient arrival interval was less than 4 minutes in 8.7%, less than 6 minutes in 28.5%, and less than 8 minutes in 55.7% of calls. Conclusions: The time from arrival on-scene to the patient's side is an important component of overall response time in large urban areas, particularly in multistory buildings. [source] | |||||||||||||