scholarly journals Assessment of the Current State of Internal Force and the Optimization of Cable Force for an Existing Long-span Pre-Stressed Concrete (PC) Cable-stayed Bridge

2017 ◽  
Vol 11 (1) ◽  
pp. 572-585 ◽  
Author(s):  
Xijun Ye ◽  
Zhuo Sun ◽  
Guoqing Huang
Keyword(s):  
Crack Resistance ◽  
Internal Force ◽  
The State ◽  
Geometric Shape ◽  
Natural Material ◽  
Cable Stayed Bridge ◽  
Cable Force ◽  
Resistance Value

Introduction: Due to the influence of load, fatigue, corrosion, natural material aging and other long-term adverse factors, the state of the internal force of a cable-stayed bridge will be changed. These long-term effects can result in the bridge not meeting specified functional requirements, and potentially resulting in structural failure. This investigation focuses on the parameter identification of a girder for a pre-stressed concrete (PC) cable-stayed bridge. Without considering the influence of cable relaxation and temperature on the girder’s geometric shape, an improved method based on the “cable force-girder’s displacement” relationship is proposed. Method: In this method, measurement variations of displacement and cable force are simultaneously obtained, enabling the use of an optimization method to identify parameters which need to be resolved. To verify the proposed method, a single pylon PC cable stayed bridge (2×160m) is selected as a case study. For the state of internal force, results from the case study bridge indicate that the crack resistance value of the girder no longer satisfies the demand of Generalized codes for design of highway bridges and culverts(JTG D60-2004,in Chinese). In order to adjust the internal force, cable force optimization was undertaken, whereby bending energy was taken as the objective function. Result: Using these results the geometric shape of the girder was restored to its initial state. The results also show that neither the crack resistance value nor the compression resistance value of the girder exceeded specified limits, and that the stress of the girder was effectively controlled.

The Length Optimization of Non-Stayed Cable Segment to Low-Pylon Cable-Stayed Bridge

2013 ◽  
Vol 274 ◽  
pp. 490-495 ◽  
Author(s):  
Hong Tao Bi ◽  
Liang Wu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Design Theory ◽  
Internal Force ◽  
Cable Stayed Bridge ◽  
Cable Force ◽  
Length Optimization ◽  
Cable Segment ◽  
Element Method

In this paper, combined with the background engineering, according to the cable-stayed bridge's design theory, through the adjustment of cable force to change the structure's internal force by using the big general finite element method software which is named Midas/Civil, and then analyzed the related parameters affecting to structural internal force and distortion, which obtained the reasonable length of non-stayed cable segment to this kind of bridge.

Measurements for Tourist Space Development

2016 ◽  
Vol 41 (0) ◽  
pp. 0-0 ◽  
Author(s):  
Leszek Butowski ◽  
Bogdan Włodarczyk
Keyword(s):  
Empirical Research ◽  
Research Method ◽  
Tourism Development ◽  
The State ◽  
Research Project ◽  
Space Tourism ◽  
Current State ◽  
The Town

Purpose. Disseminating knowledge on tourist space as a subject of study (ontological aspect) and methods for researching (describing and measuring) it, including paradigms and applied research approaches (epistemological aspect). Research hypothesis: the measure of tourism (tourist space) development is the achievement, within a given area, a state of long-term sustainability, defined as the situation in which the (widely understood) benefits outweigh (widely understood) costs of tourism development incurred by all (direct and indirect) groups of stakeholders. Method. The first part of the paper provides an overview. On the basis of the existing definitions and ways of understanding or delimiting tourist space, different measures (including measures of tourist space development) were distinguished and classified. In the second part of the paper, the results of a pilot research project investigating the state of sustainability of tourist space (tourism) in the town of Jastarnia were presented (case study). The research project was carried out using an innovative research method based on a model of sustainable tourism. This was a qualitative project and the obtained results have been quantified. Findings. The current state of tourism (tourist space) in Jastarnia was found to meet the criteria of sustainability, although certain sub-groups of respondents reported lack of sustainability in the component of costs. Research and conclusion limitations. The results of the empirical research reflect the current state (2015). The research project was carried out on a determined sample (it is not representative). Practical implications. The proposed method can be used for assessing the state of tourism at any destination. The obtained results can serve as a guide in the decision making process regarding the directions of tourism development. Originality. An innovative empirical research method has been applied. Type of paper. The first part of the paper provides an overview. The second part contains results of an empirical research project.

scholarly journals Osadnictwo żydowskie w kontekście konfliktu izraelsko‑palestyńskiego

2021 ◽  
Vol 15 ◽  
pp. 251-266
Author(s):  
Piotr Kosiorek
Keyword(s):  
Legal Status ◽  
West Bank ◽  
The State ◽  
The West ◽  
Jewish Settlement ◽  
State Of Israel

Osadnictwo żydowskie jest jednym z najważniejszych elementów wieloletnich sprzeczności między Izraelem i Palestyną. Ponadto problematyczny pozostaje tutaj status prawny osiedli. Wciąż trwa dyskusja nad tym, czy kolonie założone na Zachodnim Brzegu Jordanu są legalne, czy wręcz przeciwnie. Celem niniejszego tekstu będzie zbadanie znaczenia osadnictwa żydowskiego w kontekście konfliktu izraelsko-palestyńskiego oraz próba odpowiedzi na pytanie, jak wysoko w hierarchii priorytetów państwa sytuuje się osadnictwo żydowskie. W treści tego artykułu poruszane są takie kwestie jak mur bezpieczeństwa wraz z jego funkcjami i konsekwencjami dla Palestyńczyków, kwestia administracji Zachodniego Brzegu Jordanu oraz studium przypadku opisujące przykład Kfar Etzion i Sheikh Jarrah. Jewish settlements in the context of the Israeli – Palestinian conflict Jewish settlement is one of the most important elements of the long – term contradictions between Israel and Palestine. Moreover, the legal status of the outposts is problematical. The main objective of this text is analysis the significance of Jewish settlement in the context of the Israeli – Palestinian conflict and to try to answer the question how high in the hierarchy of the State of Israel priorities is the Jewish settlement. In a content of this article there such matters as security wall with its functions and consequences for Palestinians in the context of Jewish settlements, issue of an administration of the West Bank and the case study describes example of the Kfar Etzion and Sheikh Jarrah.

Preserving Our Heritage?

2018 ◽  
pp. 13-52
Author(s):  
Hannah Gill
Keyword(s):  
Demographic Change ◽  
Economic Transition ◽  
The State ◽  
The South ◽  
Long Term Consequences ◽  
The Impact ◽  
Latino Communities

This chapter considers the reception of migrants as an introduction to issues of demographic change and economic transition in the state. Using Alamance County as a case study, this chapter discusses how immigration has reopened debates on race, resources, and diversity in the South. It examines the impact of local deportation policies on Latino communities and considers long-term consequences for the county and state as a whole.

Transforming state–civil society relations: centralization and externalization in refugee education

2020 ◽  
Vol 63 ◽  
pp. 32-54
Author(s):  
Maissam Nimer
Keyword(s):  
Civil Society ◽  
Language Education ◽  
Humanitarian Assistance ◽  
The State ◽  
Civil Society Organizations ◽  
Refugee Education ◽  
State Institutions ◽  
The Public

AbstractIn the context of the arrival of Syrians as of 2011 and the subsequent humanitarian assistance received in light of the EU–Turkey deal in 2016, there has been increased control over civil society organizations (CSOs) in Turkey. Through the case study of language education, this paper examines the relationship between the state and CSOs as shaped by the presence of Syrian refugees and how it evolved through the autonomy of state bureaucracy. It demonstrates that increased control led to the proliferation of larger projects, the deterrence of smaller CSOs, and a hierarchy between organizations prioritizing those that are aligned with the state. It argues that this policy is not only the result of the increased lack of trust between state and civil society but also an attempt to channel funds through state institutions to handle an unprecedented number of refugees while externalizing some of its functions. At the same time, this emerging relationship effectively allows the state to avoid making long-term integration policies and facing growing tensions among the public. This study is based on a qualitative study encompassing interviews with state officials as well as stakeholders in different types of CSOs that deliver language education for adults.

Estimation and Optimization of Cable Force in Completion State of Cable-Stayed Bridge

2015 ◽  
Vol 744-746 ◽  
pp. 763-766
Author(s):  
Xun Wu ◽  
Bao Lei Li
Keyword(s):  
Internal Force ◽  
Continuous Beam ◽  
Force Estimation ◽  
Displacement Method ◽  
Cable Stayed Bridge ◽  
Completion Status ◽  
Analysis Calculation ◽  
Key Factor ◽  
Cable Force ◽  
Rigid Supports

The reasonable cable force is the key factor for the safe use of cable-stayed bridge. This paper adopts the method of continuous beam on rigid supports, zero displacement method and the internal force balanced method for cable force estimation of completion stage. The estimation value of cable force is determined by comprehensive considering various methods. With the estimate value as the initial cable force of feasible domain method, conducting the cable force optimization. Comparing the optimization with estimation value and conducting analysis calculation to ensure the rational completion status. Referring a cable-stayed bridge’s example, and conducting the estimation and optimization of cable force, the calculated results meet the requirements. The results show that the method is effective and practical.

Experimenting in Somalia: The new security empire

2017 ◽  
Vol 17 (3) ◽  
pp. 404-420 ◽  
Author(s):  
Catherine Besteman
Keyword(s):  
State Government ◽  
The State ◽  
Territorial State ◽  
The Past ◽  
The Us ◽  
A Site ◽  
Us Intervention ◽  
Security Regimes

The past several decades of US intervention in Somalia produced violent destabilization, dysfunction, and uncertainty, creating refugee outflows and terrorist networks against which the US is currently tightening its security cordons. This paper argues that Somalia’s recent history as a stateless region offers a cautionary and tragic case study of the long-term damages that ensue when wealthy states that intervene in poorer states in the name of their own security instead cause insecurity and inequities that enable violence, and then in response to that violence enact further securitization to protect themselves against the consequences of that damage. But rather than focusing on the state as a site of securitization, I focus on those whose lives are made insecure by the retreat of their state government and the imposition in its place of security regimes that are not created by their own state government. Such security regimes overlap and compete, are instituted by different state and nonstate actors for different purposes, and by their incoherence and multiplicity raise questions about the definition, location, and relevance of the state in such regions. The paper explores the emergence of new, interlinked security regimes that are partially or wholly constituted through the logics of a new security empire designed to respond to US security concerns. By turning attention to the situations faced by those who live within the insecurities of stateless regions, the paper asks, what happens to the concept of securitization when the national-territorial state is not the entity that operates as a ‘state’ in the lives of people, even though their lives are overlain with multiple and overlapping regimes of securitization?

‘This pasture is ours since ancient times’: An ethnographic analysis of the reduction in conflicts along the post-1991 Afar-Tigray regional boundary

2014 ◽  
Vol 52 (1) ◽  
pp. 25-44 ◽  
Author(s):  
Lutgart Lenaerts ◽  
Mark Breusers ◽  
Stefaan Dondeyne ◽  
Hans Bauer ◽  
Mitiku Haile ◽  
...  
Keyword(s):  
The State ◽  
Border Zone ◽  
The Past ◽  
Ancient Times ◽  
Ethnographic Analysis ◽  
Regional Boundary ◽  
Key Questions

ABSTRACTThe role of post-1991 ethnic-based federalism on conflicts along regional boundaries has been a topic of great dispute in Ethiopianist literature. This article sheds new light on the on-going debate based on original ethnographic material from the Afar-Tigray regional border zone. Contrary to other studies, conflicts appear to have reduced in that area. Two key questions are addressed: how do different groups lay future claims to land; and which role does the post-1991 government play in those claims to land and in reducing conflicts? The case study reveals that people materialise religion to lay future claims to land and that conflicts have reduced with increased involvement of the state over the past two decades, but that this reduction has come at a high cost and may therefore not be sustainable in the long term.

scholarly journals The legitimacy of extralegal property: global perspectives and China’s experience

2016 ◽  
Vol 67 (2) ◽  
pp. 189-208
Author(s):  
Ting Xu ◽  
Wei Gong
Keyword(s):  
Land Tenure ◽  
The State ◽  
Formal Property ◽  
State Law ◽  
Full Spectrum ◽  
Global Perspectives ◽  
Property Relations ◽  
The Law

Binary thinking has been entrenched in property law, posing challenges to the protection of land tenure and land users who have no title to the land they cultivate. This paper critiques the state-law-centred approach to evaluating the legitimacy of property and defends extralegal property as legitimate claims to land and related natural resources that are not against the law, but that are not recognised by the law as formal property rights. It begins with an overview of how the legitimacy of property is conceived of at the global level, drawing upon several conceptual frameworks of property developed via global initiatives and soft law instruments. That being done, it moves to examine the legitimacy of extralegal property from the local perspective, looking at a case study of ‘minor rights property’ in China. It is argued that long-term usage of land supported by the prevalence of this practice and social consensus should be regarded as one of the major sources of the legitimacy of property. The paper concludes that the state-law-centred approach to evaluating the legitimacy of property overlooks a range of legitimate property claims and the plurality of norms governing property relations. In order to recognise the full spectrum of property, we should link global perspectives with local experiences.

Analysis of Cable-Stayed Bridge for APDL-Based Optimization

2011 ◽  
Vol 243-249 ◽  
pp. 1567-1572
Author(s):  
Tao Zhang ◽  
Hai Feng Bai
Keyword(s):  
Parametric Design ◽  
Element Model ◽  
Internal Force ◽  
Steel Tube ◽  
Computational Time ◽  
Cable Stayed Bridge ◽  
Dead State ◽  
Limit Value ◽  
Cable Force ◽  
Cable Forces

Optimum design for a cable-stayed bridge structure is very complicated because of large number of design variables. Use of ANSYS parametric design language in optimizing such structure consumes little computational time. The finished dead state analysis for single pylon double cable plane cable-stayed bridge with 120m long is performed. Mechanics equivalent are developed for the main pylon with concrete-filled steel tube. Prestress girder finite element model is established also. The theory of minimum bending strain energy is used in deriving the objective function as the quadratic form of the post-tensioning cable forces. In addition, the maximum deflection of the pylon and the maximum stresses of the main girder are both implemented in the optimization model. Optimized cable forces are found by optimization. Calculated results show that after the optimization, the cable force slightly changes, yet the internal force state under dead load remarkably improves, the bending stress of girder as well as the deflection of pylon significantly decreases. All these variations are satisfied for the limit value of engineering code. The results obtained revealed that the method presented indeed leads to optimal structural performance for the cable-stayed bridge in particular, and might be a useful reference for the design of other similar bridges.

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