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1.
Using representative numerical models of eight code-designed steel moment-resisting frame buildings and several ground motions, time-history analyses are performed and a critical evaluation of Peak Horizontal Floor Acceleration (PHFA) demands is conducted. The frames are modeled alternatively as linear and nonlinear systems to isolate the effect of building nonlinearity on PHFA. In most cases, PHFA is reduced when nonlinear behavior of a building is considered; however, in some cases, significant amplification of PHFA is observed. Results from the numerical study provide insight into the trend of modal response modification factors presented taking ground motion spectral shape into account.  相似文献   

2.
Although Richard fitz Nigel's Dialogus de scaccario (Dialogue of the Exchequer) has received extensive critical attention as a source for fiscal and governmental history, its importance in relation to twelfth-century perceptions of vernacularity has been largely overlooked. Richard's work incorporates a novel and sophisticated treatment of the interaction between Latin and the vernacular languages which is integral to the success of his historical project. The source of Richard's linguistic innovation is paradoxically located in a valorisation of patrimonial heritage: in using language history to trace, shape and reify the distinguished past achievements of his own family, Richard constructs Latin etymologies which simultaneously explore the development of the vernaculars, particularly French. This presentation of etymology as genealogy enables the supple and subjective qualities of philology to be exploited both as a witness to the past and to the glory of the Norman present.  相似文献   

3.
Abstract

During the Late Stone Age, the sites of Ajvide and Jettböle were located on the seashore but in quite different marine environments. Ajvide on Gotland had direct access to the open sea of the central Baltic, while Jettböle in the Åland archipelago was surrounded by islands and skerries in the northern part of the Baltic Sea. Continuous excavations at Ajvide revealed large amounts of Cod (Gadus morhua) while herring (Clupea harengus) was found in small numbers. At Jettböle, as well, cod bones have been observed in large numbers while the skeletal remains of herring were few. In this study, soil samples of fishbone materials from Ajvide and Jettböle were sieved through screens of different mesh-sizes and then osteologically analysed. The finer screens aided the recovery of small herring bones that usually are lost when sieving through a common standard mesh-size of 4 mm. The results of the study confirmed the importance of fine-mesh sieving for the retrieval of the fishbone materials. Additionally, the achieved osteometric data indicated a difference in cod and herring size between the sites. Other factors that form our base for the understanding of Neolithic fishing strategies are: a general knowledge of the behaviour of the retrieved fish species, a reconstruction of the ancient marine environment and the abundance of fish species at each site.  相似文献   

4.
Many existing reinforced concrete buildings located in seismic regions are characterised by internal steel reinforcement made of smooth bars and stirrups with inadequate spacing. These bars could be subjected to significant compression and eventually buckle. This paper deals with a comprehensive experimental campaign investigating the compressive behaviour of smooth bars for different values of the ratio L/D, L being the restraints distance and D the bar diameter. The stress-strain relationship is then modelled ranging from an elastic-plastic behaviour identical to that in tension (L/D=5) to the elastic buckling behaviour (L/D>20). The comparison between the experimental results and the outcomes of the model confirms the accuracy of the proposed stress-strain relationship.  相似文献   

5.
Abstract

During the four seasons of excavations of the Roman town of Iovia-Botivo (present-day Ludbreg, Croatia), a smaller bath and sizeable (presumably public) building were discovered. An optimal plan for presentation was made with all due consideration for the site’s speci?c situation. The plan encompassed scholarly and professional requirements concerning conservation in situ combined with the needs of successful cultural management, thus resulting in alignment between the latter two factors as well as cost effectiveness. By applying the aforementioned principles (which served more as guidelines rather than rigid edicts) and facilitating successful, interdisciplinary cooperation between the national government, the municipal authorities, and researchers, it was possible to provide a sound, legally secure future for this site.  相似文献   

6.
The orientation of buildings in the ancient civilisations has been referred to the movements of several celestial bodies above the horizon on characteristics dates (two solstices and equinoxes). However, Muslims have used a sacred direction (qibla) towards Kaaba located in the courtyard in the Sacred Mosque in Mecca to pray and to perform various ritual acts in their daily lives since the early days of Islam. Thus, the mosques had then to orientate towards the qibla direction, being indicated by a niche in the focal point of the qibla-wall wherever they were building on the Earth. This article focuses on the mosque orientation in Turkey before the seventeenth century with regard to the astronomical knowledge derived from Arabic sources before Islam, mathematical theory and spherical computation derived from Greek sources and traditions based on the early Islamic period. The mosque orientations are compared to the qibla directions that are used in sacred geography which was determined by the producers of folk astronomy and in the application of the geometric or trigonometric formulae in mathematical astronomy.  相似文献   

7.
Abstract. The paper analyzes spatial competition among firms that sell substitute and/or complementary products. The firms first choose locations on the perimeter of a circular city and then compete in quantities (à la Cournot). Both linear and convex (quadratic) transport costs are considered. In general, multiple location equilibria are encountered. Complete agglomeration, partial agglomeration, and complete dispersion are possible. Convex (quadratic) transport cost substantially shrinks the set of equilibria obtained under linear transport cost. In general, the results obtained for a larger number of firms selling complementary products are strikingly different from those obtained under a duopoly.  相似文献   

8.
9.
A dynamic model for the estimation of the rocking and/or overturning response of a free-standing non-symmetric rigid block considering rotational and horizontal excitation is proposed. The block is situated at different levels of a building with flexible base subjected to earthquakes. Base flexibility introduces the rotational component of the excitation due to dynamic soil-structure interaction (DSSI). The model is used to assess the influence of the dynamic soil-structure interaction on the behavior of the block. An illustrative example of the proposed model for non-symmetric rigid blocks in 5-, 10-, and 15-story buildings located in soft soils considering earthquakes from different seismic sources is presented. Results show that it is important to consider kinematic effects as well as inertial effects of DSSI in the dynamic response of contents. The influence of base flexibility depends on the change of spectral intensities associated to the increase of the building structural period and is larger for higher building levels.  相似文献   

10.
Understanding hydrothermal processes during production is critical to optimal geothermal reservoir management and sustainable utilization. This study addresses the hydrothermal (HT) processes in a geothermal research doublet consisting of the injection well E GrSk3/90 and production well Gt GrSk4/05 at the deep geothermal reservoir of Groß Schönebeck (north of Berlin, Germany) during geothermal power production. The reservoir is located between ?4050 to ?4250 m depth in the Lower Permian of the Northeast German Basin. Operational activities such as hydraulic stimulation, production (T = 150°C; Q = ?75 m3 h?1; C = 265 g l?1) and injection (T = 70°C; Q = 75 m3 h?1; C = 265 g l?1) change the HT conditions of the geothermal reservoir. The most significant changes affect temperature, mass concentration and pore pressure. These changes influence fluid density and viscosity as well as rock properties such as porosity, permeability, thermal conductivity and heat capacity. In addition, the geometry and hydraulic properties of hydraulically induced fractures vary during the lifetime of the reservoir. A three‐dimensional reservoir model was developed based on a structural geological model to simulate and understand the complex interaction of such processes. This model includes a full HT coupling of various petrophysical parameters. Specifically, temperature‐dependent thermal conductivity and heat capacity as well as the pressure‐, temperature‐ and mass concentration‐dependent fluid density and viscosity are considered. These parameters were determined by laboratory and field experiments. The effective pressure dependence of matrix permeability is less than 2.3% at our reservoir conditions and therefore can be neglected. The results of a three‐dimensional thermohaline finite‐element simulation of the life cycle performance of this geothermal well doublet indicate the beginning of thermal breakthrough after 3.6 years of utilization. This result is crucial for optimizing reservoir management. Geofluids (2010) 10 , 406–421  相似文献   

11.
This article explores some of the manifold entanglements of architecture and utopia. It takes as a case study a social housing block in Vienna: the Hundertwasser‐Haus. The house was designed by the artist‐architect Friedensreich Hundertwasser and has attracted enormous attention from the architectural press and tourists. I articulate a series of architectural “movements”, manifest in Hundertwasser's design philosophy, press reportage about the house, residents' experiences of living at the house, and visitors' activities outside it. I argue that from these movements, a series of essentially unconnected utopian “moments” emerged. The article makes two contributions. First, it builds upon gathering interest in the geographies of utopia – specifically by moving beyond an emphasis upon utopian hope. It locates utopian impulses that are imbued with euphoria and joy, and which are not beset by a sense of lack. It also provides empirical examples of “unsettling” utopias of different registers (such as textual and experiential). Second, the article contributes to recent geographical approaches to studying architecture. It uses the analytical motif of movements to gain a sense of how a material building – and the idea of that building – is constituted as much by tenuous relations and disjunctures (even non‐relations) as by relations. Whereas contemporary geographies of architecture do not leave room for tenuous relations and disjunctures in their narratives, this article tries to do so. It highlights how utopian moments at the Hundertwasser‐Haus are proximate to each other: they are located metaphorically and/or literally at the house. Yet those moments neither conform to a coherent, singular narrative, and in some cases, nor do they relate to each other. The article opens debate about the significance of non‐relational sociotechnical constituents to the geographies of architecture.  相似文献   

12.
Twenty‐six tesserae (red, orange, yellow, light amber, green, blue and white) from the balneum of the villa at Faragola (Ascoli Satriano, Foggia) have been examined by colorimetry, ICP–MS, ICP–OES and SEM–EDS. Different types of calcareous sands have been used as the source of silica (network former), also providing the stabilizing agent. A natron‐type soda source served as the network modifier; however, the use of a sodium‐rich plant ash and the recycling process have been hypothesized for the production of two tesserae (FT 1 red and FT 3 orange). The colouring and opacifying agents were Cu oxide (cuprite, orange), metallic copper (red), Pb antimonates (yellow), Ca antimonates (white), a mixture of copper (Cu2+) and Pb antimonates (green), a mixture of cobalt (Co2+) or copper (Cu2+) and Ca antimonates (blue). The light amber tesserae should owe their colour to iron (Fe3+) alone or associated with sulphide (S2?) and Ca antimonates. It is likely that the Faragola tesserae were locally produced in a secondary glass workshop.  相似文献   

13.
Shake table tests were carried out on a 7 m × 5 m three-story, timber light-frame building (7.5 m height) at the TreesLab laboratory (Eucentre) in Pavia. The aim of the research was to evaluate the seismic behavior of a typical Italian prefabricated timber building and to study the interaction between the individual structural components tested in quasi-static manner in a previous experimental study. The 1979 Montenegro Earthquake ground motion, recorded at the Ulcinj-Hotel Albatros station, was selected as the ground motion for seismic tests. The maximum peak ground acceleration was scaled to 0.07 g, 0.27 g, 0.5 g. 0.7 g, and 1 g in order to evaluate the building’s performance at different levels of seismic input. More than 100 instruments were used to monitor the behavior of the building during seismic tests measuring acceleration, displacement, and forces. The visual inspection shows that the building did not show any damage during all seismic tests. However the data analysis (dynamic identification, capacity spectrum, inter-story drift) confirm that during the 1.00 g test the structure went beyond its linear elastic limit. The results obtained from this experimental study suggest that the design hypotheses commonly adopted in practice for seismic analysis (e.g., in terms of force distributions between the walls, and also the behavior factor q) are not always consistent with the real behavior of timber frame multi-story buildings, and should be backed by more accurate knowledge of the contributions of the individual structural components.  相似文献   

14.
The Roman town of Ammaia (in Marvão Region) is considered one of the most important recent findings of the Roman presence in Portuguese territory. It was settled in Republican times and abandoned in the seventh century. In this research, 17 masonry mortars and renders from the West Tower (South Gate), the residential area near the West Tower, the macellum, the peristylium, the public bath building, the podium of the temple and the portico of the forum were analysed. The methodology of chemical, mineralogical and microstructural characterization has involved several complementary techniques, including stereomicroscopy, X‐ray diffraction, thermal analysis and scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy. The results indicate that the mortars from the beginning of the town's edification were mainly composed of soil (clays). Later, during the main Roman building period, mortars were composed using a calcitic binder and the mortar composition varied according to their use and function. The samples from a period subsequent to the Roman occupation are based on a dolomitic binder. From the present study, relevant information has been acquired about the technological evolution of Roman construction in Ammaia, the historical context of the archaeological structures and guidelines for the conservation and restoration of mortars.  相似文献   

15.
Archaeological research in the Atacama Desert has recovered evidence of considerable cultural variability. This variability seems to have increased during the Late Intermediate Period (AD 950–1400). The oasis of Quillagua, located at the margins of the Loa River in northern Chile, between the Andes and the coast (70 km from the Pacific Ocean), has shown important evidence regarding this cultural diversity. The variety in the archaeological evidence found at Quillagua has been interpreted as the result of two different cultural influences at the oasis: the Pica‐Tarapacá who occupied the coastal and inland regions to the north of Quillagua and the Atacama who occupied the oasis and fertile areas southeast of Quillagua. Here, we present the results of stable carbon, nitrogen and oxygen isotope analyses of 23 individuals recovered from the Cementerio Oriente in Quillagua, in order to test whether the observed cultural variability is also reflected in diet and mobility patterns. Results from carbon and nitrogen isotope measurements indicate the importance of marine protein, as well as a contribution of maize in the diet of some individuals. Four individuals show low δ18O values, suggesting a possible highland or non‐local origin, whereas values for the remaining individuals are consistent with lowland populations. Together, the results support the idea that the Quillagua oasis represented an important site of interaction between the Tarapacá and Atacama cultures, with close contacts with the coast but also with the presence of individuals from the highlands. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

16.
Shellfish metrical data are a source of information about the exploitation of marine resources in the past. In this study, we propose a methodological approach based on the size structures of different rocky intertidal gastropod species. Three limpet species (Patella vulgata, Patella intermedia and Patella ulyssiponensis) and the toothed topshell Osilinus lineatus are studied from two sites in Cantabrian Spain: La Garma A and Los Gitanos caves over a period of 10 000 years, covering the Pleistocene–Holocene transition. Data are also supplied about a further sea snail species, the periwinkle Littorina littorea (Upper Magdalenian). A reduction in size can be seen, between the upper Magdalenian and the late Neolithic, in the case of the first four species. The explanation for this decline is probably related to the climate change that occurred in the transition between the Late Pleistocene and the Holocene, but it is possible that human impact might also have influenced shell sizes in the Mesolithic and Neolithic.  相似文献   

17.
ABSTRACT

At Gien (France), indoor floors from early Middle Ages occupation (8th–10th c. AD) are very well preserved, providing a new reference for archaeological investigation in northern France. This site is located on an outcrop, 20 m above the Loire valley, where a 15th c. castle stands now. The medieval occupation combines high-status houses with crafting and agricultural areas. They constitute a new urban nucleus, which grew 2?km east from an ancient Roman settlement. During the rescue excavation, four buildings of different status were sampled and studied using an integrated approach, combining stratigraphy, micromorphology, chemical, macro-remain and phytolith analyses. Micromorphological investigations helped to identify 74 built floors, from 0.5 to 150?mm thick, made with transformed local clay or imported silty earth. Mineral floors were covered by vegetal ones, consisting of crop processing refuse. These litters include an abundance of phytoliths and some seeds, both produced by cultivated cereals, which were processed in situ, such as Triticum durum, Secale cereale and Hordeum vulgare. The refuse above the mineral and vegetal floors were trampled. They were produced not only by domestic activities, such as cooking and eating, but also by metallurgic activities and animal husbandry. The investigation of a contemporary pit indicated that, despite the large amount of refuse, floors were well maintained and regularly rebuilt. The spatial distribution of waste indicated that a single space could be dedicated to several activities, which were not necessarily separated by new floors. Moreover, the total absence of bioturbation allowed the study of a stage of dark earth formation, by comparing it to the contemporaneous mechanical disturbance of a part of the strata which occurred when building new floors. All these results give new evidence of the richness and the complexity of the early Middle Ages town, in addition to help identifying the activities which could take place in early castral areas.  相似文献   

18.
The palynoflora of surface samples of glacial deposits from the Guandacol Formation in the Cerro Bola area of the Argentinian Paganzo Basin is documented. The existence of glacial related diamictites in this area has been previously ignored. The fossiliferous levels are located in section B of the formation, which corresponds to the earlier stages of deglaciation. The assemblage contains abundant monosaccate pollen grains whose global incoming is not older than early Namurian (Middle Carboniferous). Many species of this palynoflora are present in equivalent stratigraphic sequences of Argentina and can be referred to Sub-biozone A of the Raistrickia densa-Convolutispora muriornata Biozone (Namurian-Stephanian). New species described here are Cyclogranisporites rinconadensis and Tricidarisporites gutii.  相似文献   

19.
《Southeastern Archaeology》2013,32(3):220-236
Abstract

The Lake Jackson Mounds site (8LE1), located near Tallahassee, Florida, has long been considered to be a frontier Mississippian center. This assertion is primarily based on elaborate burial goods recovered during salvage excavations in the 1970s. Ground penetrating radar (GPR) on the two largest intact mounds at Lake Jackson revealed new information about their morphology and construction histories. These findings demonstrate that mound-building practices at the site were distinct from earlier, local Woodland mound-building traditions, and more similar to those of other Mississippian centers, such as Etowah and Moundville. Lake Jackson revitalized mound building in the Tallahassee area under the influence of external connections with groups in the Mississippian interaction network. These findings show how mound building was an integral practice for expressing and expanding Mississippian ideologies and rituals. This work also shows the utility of GPR in exploring mounds' morphologies and construction histories.  相似文献   

20.
Late Devonian trilobites from horizons close to the Frasnian-Famennian boundary in the Shogrām Formation at Kurāgh, Chitral (NW Pakistan) are described. A new species of Asteropyginae, Neocalmonia chitralensis sp. nov., and a new subpecies, Neocalmonia batillifera orientalis subsp. nov., are described; these extend the range of Asteropyginae eastwards from Iran and southern Afghanistan. The Upper Kellwasser Event is located within KUR 19 of Talent et al. (1999).  相似文献   

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