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1.
在明代,由于水患频发和长江主泓变动等原因,湖广武昌府城沿江江岸屡屡崩陷,当地政府遂启动江岸修筑工程。考诸史志,明代武昌府城的江岸修筑主要约有四次,分别是正统七年(1442)、成化三年(1467)、万历十七年(1589)和万历三十四年(1606)。最终修成的江岸,自武昌府城南门望山门外(今武昌解放路南端解放桥附近)起,向西折至江边,又沿江边中经黄鹤矶向下游延伸至坛角地区(今武昌和平大道武汉工人文化宫以西),长约5公里。这条堤岸确定了武昌城沿江江岸的基线,将武昌城的城市空间扩展到江边,并延续至今。  相似文献   
2.
We exploit a recent generalization of the Thrust Network Analysis (TNA) to analyse masonry structures of extremely complicated and audacious geometry such as helicoidal staircases. Actually, differently from available methods, based on ad-hoc solutions holding for each particular structure, the TNA allows for studying the equilibrium of structures of arbitrary shape by invoking the principles of limit analysis of masonry structures dictated by Heyman. Four paradigmatic monumental staircases, with increased degree of complexity, have been selected as case studies in order to show the versatility and accuracy of the proposed approach. The results entailed from the generalized TNA are also successfully compared, for the first time in the literature, with those related to the adoption of available analytical methods for the analysis of no-tension membranes.  相似文献   
3.
ABSTRACT

The “Quartel das Esquadras” is an 18th century infantry barrack located within the limits of the bulwarked fortress of Almeida, in Portugal. An ongoing adaptive reuse project of the building aims to recover its full capacity and also its importance, by implementing a variety of new uses. The architectural intervention results in the need of the structure to withstand new and diverse imposed loads. As the current configuration of the structure will be altered, the main objective of this article is to evaluate the suitability of some of the proposed structural interventions. The current condition has been characterized following a multidisciplinary approach comprising historical research, visual inspection, non-destructive testing, and structural analysis to identify the possible sources of major structural problems. A portion of the building particularly affected by the alterations has been selected to carry out structural analysis. A comparative safety assessment of the selected area in both current and altered condition has been done through finite element modelling and nonlinear static analysis, resulting in an identification of the weaker points against the new implemented loads and alterations. Finally, proposals for the implementation of the studied intervention, as well as recommendations for future research and analyses, have been given.  相似文献   
4.
This article aims at presenting and discussing the strategies for updating the finite element numerical modeling of stone masonry arch bridges using operational modal analysis. The study comprehended three bridges: two old ones, the St. Lázaro and the Lagoncinha bridges, and a recently constructed bridge in Vila Fria, Portugal. Updating of the bridge models is performed by comparing the numerical and experimental modal parameters. Three-dimensional detailed numerical models are used to perform modal analysis of the bridges. Experimental modal identification of the bridges is based on the measurement of their acceleration responses during normal operation. The assigned material properties are also based on available results obtained from in situ and laboratory tests and on the results of visual inspection and historical research carried out for both old bridges.  相似文献   
5.
Through the assistance of trace element and petrographic analyses on 14 samples of mortar aggregates from Roman monuments, including the Porticus Aemilia, the Temple of Concordia, the Temple of the Dioscuri, Temple B and other structures of the Area Sacra di Largo Argentina, and the Villa di Livia, we establish the source area and we investigate the chronological employment of the volcanic materials used in ancient Rome's masonry. In contrast to previous inferences, the petrochemical data presented here show that systematic exploitation of the local ‘Pozzolane Rosse’ pyroclastic deposit has occurred since the early development of concrete masonry, at the beginning of the second century bc , through the early Imperial age. Subsequently, exploitation was extended to the overlying Pozzolane Nere and Pozzolanelle deposits. Only during the early phase of development of the concrete masonry in Rome, volcaniclastic sediments outcropping near the construction sites were mixed with the sieved remains of the tuff employed as the coarse aggregate, to produce the fine aggregate. The results of the study on the investigated monuments suggest the possibility of establishing the chronological identification of three different types of mortars, as a function of the composition of the volcanic material employed in the fine aggregate, which, when implemented by future studies, may contribute to the dating of monuments and archaeological structures.  相似文献   
6.
Buddhist monasteries in Sikkim Himalayas constitute important religious and architectural heritage. These random rubble (RR) stone masonry structures located in high seismically active regions of the Himalayas have suffered varied degrees of damages in the past earthquakes. The study presents seismic vulnerability assessment of four archetypal monastic temples using finite element (FE) analyses. Linear and nonlinear analyses of these structures were conducted in Abaqus FE environment. These analyses identified the damage prone areas of the structures and provided load-deformation behavior under lateral loads. Fragility analyses indicate a high probability of collapse for the specified design level earthquake of the region. The study shows that performance of the structure can be enhanced by improving the strength and stiffness of the stone masonry walls.  相似文献   
7.
Tie-rods are essential structural elements, which have been employed for centuries in masonry historical buildings, either during the construction or in successive strengthening interventions, with the aim of containing dangerous horizontal actions. The actual work conditions of these tie-rods, which are strongly influenced by their load history, are difficult to be quantified theoretically, and an effective method for their measure is of great importance in order to ensure the efficiency of these elements during the time and the stability of the entire building. Common measurements are often carried out adopting models based upon significant simplifications, like, for example, hinges at the extremities. These assumptions, rarely represent the real work conditions for anchorages. In this work, a non-destructive testing method is presented, based upon sophisticated dynamical models that can take into consideration many of the circumstances neglected by the simplified models. Four case studies are extensively described, trying to embrace the most common situations in term of peculiar features of the building, structural configuration, and load history. The discussion of the results yields the safety margin of the rod with respect to the material failure and provides important indications about the overall stability of the whole building.  相似文献   
8.
The emergence of anti-democratic movements is a central puzzle to social science. We study a novel and rich historical dataset covering Swedish municipalities during the interwar years and find a strong link between the presence of a military garrison and the emergence of fascist parties. We interpret these results as suggesting that fascist mobilization in Sweden was driven by discontent with the process of disarmament brought about by democratization. In contrast, poor economic conditions, as captured both by levels of and changes in the local poverty rate and tax base, do not explain the strong link between the fascists and military garrisons. We relate these results to influential theories of democratization.  相似文献   
9.
This article narrates the role of oral testimony in the fieldof Abraham Lincoln studies from 1865 through the 1930s. Collectedin the form of letters, affidavits, and face-to-face interviews,this mounting body of "eyewitness evidence" dominated the discoursefor two generations and reflective, public practice culminatedin the organization of a "Lincoln Inquiry" in the Midwest duringthe 1920s and 1930s. For a time, practitioners successfullydefended themselves against increasing positivist assaults onthe credibility of oral testimony. Their interests and effortsresonate with later oral history practice and theory about method,authorship, performance, and memory, and their story highlightsthe contingency inherent in the development of oral historicalpractice in America.  相似文献   
10.
The delphinal counsellor Mathieu Thomassin composed a Breviere des anciens droys … du Dauphiné de Viennoys (c.1453) after a career of 30 years in the service of Charles III (the French king Charles VII) and Louis II (the future Louis XI). This was his first major historical text in French, but has been overshadowed by his better-known Registre delphinal, commissioned by Louis II in 1456. This article analyses the historical culture and the conception of history revealed in the Breviere. It notes how Thomassin's careful definitions of frontiers in the past and present reflect his experience of territorial disputes. History and geography are imbued with polemic, however, allowing Thomassin to override competing claims to territory or autonomy by delphinal opponents within and outside the Dauphiné. The principles set out in the Breviere were refined and extended in the Registre. However, it is unlikely that either work was ever intended for wide circulation; rather, they were written to provide ‘authentic’ texts which could be consulted primarily by other delphinal officers. As such, they reflect on occasion the divergence of views between a proto-professional administrator, with a concern for the long-term, and his preoccupied (if not dilettante) prince, much more subject to the requirements of realpolitik.  相似文献   
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