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1.
This paper gives insight into the use of underground space in Helsinki,Finland.The city has an underground master plan(UMP) for its whole municipal area,not only for certain parts of the city.Further,the decision-making history of the UMP is described step-by-step.Some examples of underground space use in other cities are also given.The focus of this paper is on the sustainability issues related to urban underground space use,including its contribution to an environmentally sustainable and aesthetically acceptable landscape,anticipated structural longevity and maintaining the opportunity for urban development by future generations.Underground planning enhances overall safety and economy efficiency.The need for underground space use in city areas has grown rapidly since the 21 st century;at the same time,the necessity to control construction work has also increased.The UMP of Helsinki reserves designated space for public and private utilities in various underground areas of bedrock over the long term.The plan also provides the framework for managing and controlling the city's underground construction work and allows suitable locations to be allocated for underground facilities.Tampere,the third most populated city in Finland and the biggest inland city in the Nordic countries,is also a good example of a city that is taking steps to utilise underground resources.Oulu,the capital city of northern Finland,has also started to ‘go underground'.An example of the possibility to combine two cities by an 80-km subsea tunnel is also discussed.A new fixed link would generate huge potential for the capital areas of Finland and Estonia to become a real Helsinki-Tallinn twin city.  相似文献   

2.
Cultural heritage is seen as a cultural capital. The heritage tourism increases the local employment and income, however, brings some problems at the same time, changing the traditional living way and industrial structure. The sustainability of economic development by tourism is also questioned. Fujian Tulou is a world heritage site in China, inscribed in 2008. The nomination has brought great changes to the sites, especially the flourishing tourism industries by the local communities as well as the tourism companies. The latter also take part in the management of the heritage site and get most of the income. The data in economic areas is analyzed in this study and explains the cultural tourism as a positive drive for the local economy, which contributes little to the life of locals. With the analysis of the changes and benefits from the tourism, we have found that tourism, as a dominant industry, might be a potential negative element for heritage conservation. According to the different situations of sites in Fujian Tulou, a proper planning of management is in need to integrate the tourism, conservation and development.  相似文献   

3.
Abstract: This paper presents the results of laboratory testing on a heavily compacted sand-bentonite mixture. To measure the soil-water retention curve (SWRC) of the mixture over a large range of suction, a pressure plate apparatus and filter papers were used. The obtained SWRC shows that the measurements via the two methods consistently agree with each other. By using a suction-controlled oedometer for unsaturated soils, a series of one-dimensional compression tests were performed on the unsaturated compacted sand-bentonite mixture at different constant suctions. The testing results indicate that the yield stress increases and compression index decreases with the increase of imposed suction. The results also demonstrate that the mixture wetted to saturation and subsequently dried to a certain suction level has a lower yield stress than that wetted directly to the same suction.  相似文献   

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5.
In order to achieve high quality that not only gives acceptable return value to society but also satisfies the needs of all the stakeholders of infrastructure projects, comprehensive understanding of issues pertaining to the quality of the project is needed. The aim of this study is to provide an overview the most common procurement methods used in constructing infrastructure transport projects and analyze how these methods contribute to the desired quality of the final product in relation to client competence. An on-line survey of construction actors was carried out to ascertain quality level of Swedish infrastructure transport projects and determinant factors of quality problems. An equal number of respondents indicated that the quality of infrastructure projects has either increased or remained same level over the past twenty years. Respondents also pointed out lack of client competence that is vital in realizing the desired quality level through proper procurement, monitoring and evaluation procedures. Public clients heavily rely on traditional design-build procurement that requires considerable client involvement of a project. Thus, the association of quality problems and lack of client competence may not be a mere coincidence but an overlooked outcome of current situation.  相似文献   

6.
A new experimental approach to assess the impact of soil confinement on the long-term behavior of geosynthetics is presented in this paper.The experimental technique described herein includes a novel laboratory apparatus and the use of different types of tests that allow generation of experimental data suitable for evaluation of the time-dependent behavior of geosynthetics under soil confinement.The soil-geosynthetic interaction equipment involves a rigid box capable of accommodating a cubic soil mass under plane strain conditions.A geosynthetic specimen placed horizontally at the mid-height of the soil mass is subjected to sustained vertical pressures that,in turn,induce reinforcement axial loads applied from the soil to the geosynthetic.Unlike previously reported studies on geosynthetic behavior under soil confinement,the equipment was found to be particularly versatile.With minor setup modifications,not only interaction tests but also in-isolation geosynthetic stress relaxation tests and soil-only tests under a constant strain rate can be conducted using the same device.Also,the time histories of the reinforcement loads and corresponding strains are generated throughout the test.Results from typical tests conducted using sand and a polypropylene woven geotextile are presented to illustrate the proposed experimental approach.The testing procedure was found to provide adequate measurements during tests,including good repeatability of test results.The soilegeosynthetic interaction tests were found to lead to increasing geotextile strains with time and decreasing reinforcement tension with time.The test results highlighted the importance of measuring not only the time history of displacements but also that of reinforcement loads during testing.The approach of using different types of tests to analyze the soilegeosynthetic interaction behavior is an innovation that provides relevant insight into the impact of soil confinement on the time-dependent deformations of geosynthetics.  相似文献   

7.
When we travel around the world, we will hear different languages from different national people; in the same way, when we have a journey round one country, we will find different people in different regions speak differently more or less. But we also can encounter this situation that people of the same language cannot understand with each other, and people from different languages can communicate with each other freely. What can we explain about this phenomenon? In this paper, I want to say something about this issue through the basic ideas of language and dialect.  相似文献   

8.
Following the foundation failure of a building, with an aim of economical solution to strengthen other existing buildings of the same project, a new arrangement was implemented experimentally to test the adequacy of load bearing capacity of a few selected cast-in-situ RCC (reinforced cement concrete) pile groups without demolishing the existing buildings. In this test, the column bottom of an existing building was removed by the help of scaffolding and after that a frame system consisting tension piles and hollow beam was constructed over the pile cap of the to be tested pile group. The load was tested by the help of hydraulic jack system and the constructed frame system. This paper contains the detailed plan, arrangement and method of the test with illustrations. The deflection and loading data analysis is also included which was performed to determine the outcome of the test. Through this test method the appropriate assessment of capacity of pile group of existing building could be done successfully and in result the structure could be saved by only super structure retrofitting.  相似文献   

9.
The aim of this study is to identify the influence of the dip angle of a pre-existing macrocrack on the lifetime and ultimate deformation of rock-like material. Prediction of lifetime has been studied for three groups of specimens under axial static compressive load levels. The specimens were investigated from 65% to 85% of UCS(uniaxial compressive strength) at an interval of 10% of UCS for the groups of specimens with a single modelled open flaw with a dip angle to the loading direction of 30°(first group), at an interval of 5% of UCS increment for the groups of specimens with single(second group), and double sequential open flaws with a dip angle to the loading direction of 60°(third group). This study shows that crack propagation in specimens with a single flaw follows the same sequences. At first, wing cracks appear, and then shear crack develops from the existing wing cracks. Shear cracking is responsible for specimen failure in all three groups. A slip is expected in specimens from the third group which connects two individual modelled open flaws. The moment of the slip is noticed as a characteristic rise in the axial deformation at a constant load level. It is also observed that axial deformation versus time follows the same pattern, irrespective of local geometry. Specimens from the first group exhibit higher axial deformation under different load levels in comparison with the specimens from the second and third groups.  相似文献   

10.
Unbalanced with its rapid development in urban construction and economy,China’s social development is lagging behind a fair amount.As an important policy means to guarantee social equity and public benefit,urban planning should play its inevitable role in solving social problems and promoting harmonious social development,while at the same time it exposes certain limitations of traditional Chinese urban planning mainly focusing on physical planning in both theoretical and methodological aspects.Aimed at the relevant social problems caused by simple physical planning at present,this article attempts to study out a research framework of social planning suitable for China’s urban planning as a monographic study,so as to introduce a people-oriented view of social development into the key contents of urban planning,and to provide ameliorative strategies to supplement and improve the planning concept,procedure,contents and methods.This article also briefly introduces the perspectives and key contents of social planning.  相似文献   

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