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1.
Sewerage systems first appeared in Paris in the middle of 19th century. Even if the majority of structures are still in working order, their general state will deteriorate inexorably, and as reconstruction is not always possible for cost and social impact reasons, rehabilitation is a solution adopted by many clients. It is necessary to resort to new rehabilitation techniques. Reinforcement by bonding composite materials has many advantages compared to other techniques. The objective of the experimental campaign presented in this paper is to study the addition of a lining by means of mortar reinforced by thin composite materials so as to restore masonry structures. To that purpose, crushing tests on masonry vaults have been carried out. The application of a lining made of mortar reinforced with composite materials has allowed increasing the breaking load and delaying the occurrence of the first cracks. This article presents the characterization of the materials. Moreover, the results of the breaking tests applied to masonry vaults are shown in this paper. A comparison with a traditional type of rehabilitation by a 6 cm-thick shotcrete lining will be performed.  相似文献   

2.
Different artificial intelligence(AI)methods have been applied to various aspects of rock mechanics,but the fact that none of these methods have been used as a standard implies that doubt as to their generality and validity still exists.For this,a literature review of application of AI to the field of rock mechanics is presented.Comprehensive studies of the researches published in the top journals relative to the fields of rock mechanics,computer applications in engineering,and the textbooks were conducted.The performances of the AI methods that have been used in rock mechanics applications were evaluated.The literature review shows that AI methods have successfully been used to solve various problems in the rock mechanics field and they performed better than the traditional empirical,mathematical or statistical methods.However,their practical applicability is still an issue of concern as many of the existing AI models require some level of expertise before they can be used,because they are not in the form of tractable mathematical equations.Thus some advanced AI methods are still yet to be explored.The limited availability of dataset for the AI simulations is also identified as a major problem.The solutions to the identified problems and the possible future research focus were proposed in the study subsequently.  相似文献   

3.
The award of the Pritzker Prize for architecture to Glenn Murcutt recently may have come as a surprise to some architects internationally, but it was a decision received with some sense of inevitability in Australia. Australians constantly monitor their status worldwide, and have been conscious for some time that Murcutt has replaced Harry Seidler as our most visible architect internationally.  相似文献   

4.
The colonization of Sicilian latifundium was an attempt of regeneration of the rural areas. It was carried out by Benito Mussolini, called II Duce, who governed Italy by a regime with an absolute and conservative approach for 20 years since 1922. According to this plan, there were some rural villages (with a school, a church, a police station and a doctor's surgery) and a number of rural homes, spread in the landscape, that formed one of the most important achievements of the agrarian reform in Italy. The author has been conducting scientific research on this topic for several years. He started with the archive "Ente per la Colonizzazione del Latifondo Siciliano" (now called Ente Sviluppo Agricolo) to review the original designs and contracts with companies, ledgers and other administrative documents. Lately, he has been reviewing the personal archives of designers involved in the building program, where he has found original drawings, letters, sketches, etc.. He has also conducted some architectonic and technical surveys of the sites. We have to consider that nowadays the mentioned rural villages are a strategic resource for the development of the neighboring areas, as it may become a network for the sustainable tourism and the promotion of the local agro food specialties. On this purpose, the local authority is going to promote some plans for the requalification of these sites. The particular achievement of this article is to show a number of possibilities for the reuse of these places.  相似文献   

5.
Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footbridges, a series of field tests and numerical analyses have been carried out. In the paper, the results of the dynamic field tests of three medium span concrete footbridges with different structural systems (frame, beam and arch footbridges) and their dynamic characteristics (mass, stiffness and damping) are presented. The field tests were carried out for different types of vibration excitation caused by walking, running and jumping persons. Furthermore, the vibrational comfort criteria for footbridges are shortly described and verified for examined structures. The study were supplemented by numerical calculation of natural mode shapes and frequencies of the structures using the 3D FEA (finite element analysis) models with elastic supports elements in order to ensure the compatibility of the calculated and measured mode shapes of the footbridges.  相似文献   

6.
Although the cyclic rotation of the principal stress direction is important,its effect on the deformation behavior and dynamic properties of the reinforced soil has not been reported to date.Tests carried out on large-scale hollow cylinder samples reveal that the cyclic rotation of the principal stress direction results in significant variations of strain components(ε_z,ε_r,ε_θ and γ_(zθ)) with periodic characteristics despite the deviatoric stress being constant during tests.This oscillation can be related to the corresponding variations in the stress components and the anisotropic fabric that rotate continuously along the principal stress direction.Sand under rotation appears to develop a plastic strain.Similar trends are observed for reinforced sand,but the shear interaction,the interlocking between particles and reinforcement layer,and the confinement result in significant reductions in the induced strains and associated irrecoverable plastic strains.Most of the strains occur in the first cycle,and as the number of cycles increases,the presence of strains becomes very small,which is almost insignificant.This indicates that the soil has reached anisotropic critical state(ACS),where a stable structure is formed after continuous orientation,realignment and rearrangement of the particles accompanied with increasing cyclic rotation.Rotation in the range of 60°-135° produces more induced strains even in the presence of the reinforcement,when compared with other ranges.This relates to the extension mode of the test in this range in which σ_θσ_z and to the relative approach between the mobilized plane and the weakest horizontal plane.Reinforcement results in an increase in shear modulus while it appears to have no effect on the damping ratio.Continuous cycles of rotation result in an increase in shear modulus and lower damping ratio due to the densification that causes a decrease in shear strain and less dissipation of energy.  相似文献   

7.
8.
Urban growth has been a major issue in environmental monitoring and changes occurred on land surfaces have been monitored by applying remote sensing as well as ground measurement. Most major cities in the world have experienced land subsidence phenomena on some parts of them due to the load of development and modernization. Excessive extraction of groundwater for the needs of industry has led to the condition where the water table drops, and this can possibly trigger subsidence, as observed in Indonesian cities. In this study the authors have shown that the application of DInSAR (differential interferometric synthetic aperture radar) technique using Japanese Earth Resources Satellite-I Synthetic Aperture Radar JERS-I SAR data can reveal subsidence conditions in the studied Makassar city area. Landsat TM (thematic mapper) images were used to evaluate the change of land cover during the observation period of 1994-1999. Makassar is fiat, covered mainly by alluvium deposit that is vulnerable to the load of constructions, and volcanic formations which is porous and will easily be degraded by groundwater extraction. It is found that mostly the subsidence has occurred in the western part of the city, including the industrial district, reclamation area, trading center area and the seaport area. The ground survey has indicated that high human activity exists in every point of subsidence. It is likely that various human activities such as ground water pumping and construction work should have affected the local subsidence phenomena in Makassar, as in the case of other large-scale cities in Indonesia.  相似文献   

9.
The study presented in this paper discusses a discontinuum-based model for investigating strength and failure in sedimentary rocks.The model has been implemented by UDEC to incorporate an innovative orthotropic cohesive constitutive law for contact.To reach this purpose,a user-defned model has been established by creating dynamic link libraries(DLLs)and attaching them into the code.The model reproduces rock material by a dense collection of irregular-sized deformable particles interacting at their cohesive boundaries which are viewed as flexible contacts whose stress-displacement law is assumed to control the fracture and the fragmentation behaviours of the material.The model has been applied to a sandstone.The individual and interactional effects of the microstructural parameters on the material compressive and tensile failure responses have been examined.In addition,the paper presents a new methodical calibration procedure to ft the modelling microparameters.It is shown that the model can successfully reproduce the rock mechanical behaviour quantitatively and qualitatively.The study also shows how discontinuum-based modelling can be used to characterize the relation between the microstructural parameters and the macro-scale properties of a material.  相似文献   

10.
Based on qualitative data from in-depth interviews,participative observation,and literature study,this paper aims to get insights into the patterns and process of the citizenization of native villagers living in Liede Community,which is the first redeveloped urban village in Guangzhou.Investigation on villagers’ citizenization level is carried out to examine how the redevelopment project affects villagers’ citizenization.Our finding reveals that the redevelopment project has improved villagers’ living conditions and income levels remarkably,has facilitated the mixed housing patterns of diversified social groups,and has increased their chances to be integrated into urban social life.Nevertheless,as villagers kept their traditional mode of thinking,behavioral habits,and lifestyles,the citizenization process made little progress in terms of land ownership,management mode,mode of livelihood,and citizen identity.Therefore,the Liede redevelopment project has turned out to be a "passive citizenization" process,i.e.,villagers merely received socio-economic benefits from the redevelopment passively but remained isolated from the socio-economic and cultural system of the city.Finally,this paper proposes some policy suggestions to promote the citizenization from both conceptual and practical perspectives.  相似文献   

11.
As of 1990, the housing stock in Latvia has decreased mainly due to the exclusion of flats and decreasing investment in residential buildings among others. The article gives a brief introduction of the privatization process of apartments carried out after 1991 as one of the fundamental principles of independence and prosperity of Latvia. It also emphasizes the need of housing renovation based on the age and poor building techniques of most of the houses, and the importance of energy efficiency in building sector for which some programmes have been launched. Finally it illustrates the role of the Government in housing supply through such activities as developing the National Building Programme, providing policy guidance, housing monitoring and offering significant financial support.  相似文献   

12.
Abstract The slogan"One Country,Two Systems"guides the political,economic and cultural development of Hong Kong–one of the world’s most important financial centers.However,the city is more than just a financial center and a tradehub.The city also has a strong civil society,and the members of the civil society have much interest in culture and cultural identity.The city aims to strengthen its position as a prominent center of higher education in Asia.Therefore,cultural facilities,infrastructure,festivals(such as the Hong Kong Film Festival)and culturerelated fairs,as well as cultural and creative industries,are high on the political agenda,dedicated to promoting Hong Kong to be a cultural center in Asia.In recent years,a number of studies have been commissioned to explore the potential of cultural and creative industries under the urban economy.The findings suggest that cultural and creative industries are one of the economic development fields that the Hong Kong Special Administrative Region(HKSAR)Government should support and promote in the future.A design center and agency,called Cyberport,has been established to create institutions that can support the evolution of cultural and creative industries.In addition,the Hong Kong Special Administrative Regional Government of China decided in 2008 to develop a prime location in the middle of the city into a cultural district.The West Kowloon Cultural District will position the city on the cultural map of Asia.  相似文献   

13.
The aim of this paper is to present the development of shopping centres in Poland after its political transition. From that time, all types of shopping centres were built, starting from the very basic first generation and developing into the most current formats. In the article, types of shopping centres are compared to their western origins. Planning laws and procedures that apply to the processes are also described, with an example of a law that was introduced to specifically control growth of shopping centres. Apart from that current trends and growth possibilities in the present market situation are discussed. As a result, a very rapid development process was observed, with little hampering from the planning policies. This may be used as a point of reference for other countries that have not yet encountered that process.  相似文献   

14.
World cities are facing greater exclusion and marginalization. A recent research study has shown that it is not the large multinational companies, but the small and medium enterprises, and increasingly the micro-businesses,which succeed in providing the much needed employment. Regardless of their social level, a large portion of the population in developing countries has turned to micro-businesses in search of survival. The degree of vulnerability of micro-businesses pushes them to seek out the informal sector, which over time becomes their main obstacle to growth. Therefore, the idea of viewing the “informal city“ as an opportunity to solve the problem of structural poverty, rather than a problem or a threat to be eradicated, is significant for building genuine and truly “global“ cities.  相似文献   

15.
This paper makes a systematic analysis on the development characteristics and evolution process of the built-up areas,as well as the sub-structure of the network connectivity and the functional division,of core cities in the Guangdong-Hong Kong-Macao region from the dual perspectives of "space of places" and "space of flows." It does so by using data of satellite remote sensing and industrial census to describe the spatial development trend and to establish an urban connectivity network based on the headquarter-branch data of enterprises.It also reveals the development differences within and outside of the Bay Area in Guangdong Province.The research shows that,firstly,since the new century,the integration of the Bay Area has become more obvious for Guangdong-Hong Kong-Macao region,as it has developed in a highly-concentrated way around the Bay Area of the Pearl River Estuary.Secondly,Guangdong,Shenzhen,Hong Kong,and Macao exhibited a more obvious regional division of labor,and their functions have been increasingly complementary to each other.Thirdly,a regional hub of "two sectors"–linking outside to the world city network and driving internal development of regional hinterland has been formed.Finally,based on the conclusion of the empirical research,development and planning implications of the Bay Area are discussed.  相似文献   

16.
Building construction site plays an important role in the economic aspect of a region. So any disruption due to hazard event like earthquake can cause several direct and indirect damages. Direct damages can lead to the loss of equipments and qualified persons. Indirect damages can lead to inflation and loss of purchasing power. To deal with that situation, parameters that govern the vulnerability of building construction site have been identified. Using a MCDM (multiple criteria decision making) method, the priority order of these parameters has been set. Then a PVI (partial vulnerability index) and a GVI (global vulnerability index) are proposed. These indexes allow the classification of building construction sites according to their intrinsic vulnerability and seismic vulnerability respectively that is through the use of a given classification. Several Algerian building construction sites belonging to different seismic zones were considered in order to show the applicability of the method.  相似文献   

17.
Since China adopted the policy of reform and opening to the outside world, the ur-ban-traffic problem has become more and more severe with each passing day. With theconcerted efforts of the professionals from all over the country, and by introducing newtheory, applying new technologies and new methods and by preserving in continuouspractice and exploration, we have obtained gratifying experience and results in trying tosolve the problem. Following is a historical review of the work we have done in trying tofind the solutions to traffic problems. Meanwhile, the author also points out that in thenext ten years, the task of China's urban traffic-planning is still very arduous and more ef-forts should be made in this respect to meet the needs of our economic development.  相似文献   

18.
Extra-cellular compounds, secreted by microorganisms into their surroundings, can be integrated in concrete composition as admixtures. These substances are important in biofilm formation and some of them can be used as corrosion inhibitor of concrete reinforcement. This paper deals with products made with biological surface active compounds/agents allowing the development of more eco-friendly concrete. The influence of this environmentally friendly bio admixture on setting time, workability, bending and compressive strengths of various mortar based materials made of CEM I, CEM III and CEM V was studied. Mechanical tests were carried out to highlight the influence of admixture in workability and hardening of samples containing the biological product with ratio in the range of 0-2.5%. It was demonstrated that the presence of the new bio-compound admixture in mortar decreases their compressive strength after 28 days of standard curing, in spite of remaining higher than standard minimal strength. Furthermore, Vicat needle experiments have shown a tendency of this admixture to decrease the setting time. A discussion was finally proposed in order to correlate the setting times and the decrease of the mortar compressive strength, corresponding in fact to a hardening delay. This setting time delay could be linked to a delay of the admixtured mortar to increase its resistance. The slump results highlight the action of bio-admixture as a plasticizer on mortars because it increases their workability for a same water-cement ratio. This effect seems variable according to the added amount.  相似文献   

19.
Tourism has become the world's fastest growing sector due to acceleration of technology and information flow in the globalized world of today, development of the modem mass transport system and increase in people's disposable income. Upon tourism's being considered as a serious development strategy in the developments of the countries, all the countries of the world have begun to accelerate their investments in this area through utilizing the natural and cultural assets of their countries (heritage) with a view to provide revenue to their economy as well as creation of jobs. This situation, which has emerged as a result of the globalization of supply and demand in tourism, has created certain problems in terms of environmental balance and the living conditions of local people as a result of poor management of the utilization of natural and cultural resources. The objective of this paper is to examine the concepts and principles germane to sustainable tourism which has significant contribution to the development of the countries, made at the macro level both in the world and in Turkey. The aim of this paper, at the micro level, is to create awareness incident to the tourism resources of the Van Region and the Old Van province and ensure the utilization of these resources through protection thereof. At the end of the study, the importance of the protection of heritage resources as well as fair use thereof in terms of increasing the competitiveness of Turkey on a global scale in tourism is addressed in the light of the overall evaluations.  相似文献   

20.
The study, carried out within the LogNet research project financed by Calabria region, deals with the analysis of the automotive supply chain. In particular, after a first examination of the characteristics of the whole automotive supply chain, attention was focussed on its final part, that is, on transport and end-market distribution. The paper proposes specific models, which are differentiated by the transport mode (road, rail, sea) they are involved, to estimate the temporal and monetary costs related to the activity of goods distribution to the compounds/end-clients. The proposed mode/ling formulations concern two different areas of investigation: the network segment and interchange nodes. Each cost item is also calculated through aggregate formulations (where the cost is function of a single significant variable in relation to a unit cost parameter) and disaggregate formulations (where each cost item is separately considered). The models have been applied to a study carried out for the modal transfer of vehicles in the port of Gioia Tauro, south of Italy. The analysis has allowed, on the one hand, to calibrate certain models and, on the other, to simulate certain scenario hypotheses to verify the technical feasibility of a different structure for the automotive supply chain in Italy.  相似文献   

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