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1.
Kuwait–Georgian archaeological work at Failaka Island showed the need for geological study. Analysis of sediments related to drinking water-collecting cisterns was performed on a Late Islamic settlement (NE part of the island) in 2018. Field sedimentological, grain size and XRD analysis of the sediment profiles showed that the shallow (about 1 m deep) cone-shaped wells are dug in the loose, porous, cross-stratified calcareous coarse-grained quartz sandstones. Three upper layers of quartz sandstones in the profile have high infiltration rate and provide a rare yet ideal material for water retention. The fourth dense layer below, composed of very fine sand and silt fraction, tends to hinder water movement and forms a relatively impermeable water-resistant surface. Thus, the distribution patterns of clay content, grain sizes and porosity of the well-hosting sediments are favourable for freshwater infiltration and harvesting. An additional petrographic analysis was conducted on different types of rocks discovered on the archaeological site, used as building material and fragments of stone artifacts to identify their origin. It was established that archaeological building material is of local origin, whereas the source rocks for stone artifacts were imported.  相似文献   
2.
Many factors governed the penetration efficacy of prehistoric projectile weaponry. Archaeologists broadly focus their efforts on understanding the effect of stone weapon tips because these specimens are often the only part of the weapon system that survives in the archaeological record. The tip cross-sectional area (TCSA) and perimeter (TCSP) of stone weapon tips have been shown to correlate with target penetration depth. Here, using results from both static and dynamic penetration testing, we compare TCSA and TCSP against other tip geometry metrics: lateral surface area (LSA) and volume (V). Our analyses broadly show that using a single-point geometry metric evaluated at multiple locations along the length of the point, or using multiple geometry metrics evaluated at a single location, better predicts required energy than using a single-point geometry metric evaluated at a single location. Our results also show that in the case where a single geometry metric evaluated at multiple locations is used LSA provided the most robust prediction models. Finally, our results show that for the case where all geometry metrics evaluated at a single location are used the location that provides the most robust prediction model is dependent on how far the point penetrated the target.  相似文献   
3.
We use trace element discrimination diagrams to provide a geochemical fingerprint for Tufo Lionato, the volcanic rock most commonly used in the ancient Roman dimension stone technique. Based on the comparison of their geochemical signatures, we identify different rock facies of Tufo Lionato employed since the fourth to third centuries and through the second century bce in the construction of the temples of the Area Sacra di Largo Argentina. These rock facies correspond to two previously identified building stones: Aniene Tuff and Monteverde Tuff, named after their supposed source areas located in the Aniene River Valley and in the homonymous locality of the Tiber River Valley, respectively. However, the results of our study demonstrate previous misidentification of these volcanic rocks in the different construction phases of Temple C, providing a revision of the dating system currently accepted for the diffusion of Tufo Lionato architecture. We show that the Aniene facies has been exploited since the end of the fourth century bce and that it was employed along with Tufo Giallo della Via Tiberina in the podium and staircase of Temple C, whereas observations at Largo Argentina suggest that the ‘Monteverde Tuff’ was only sporadically used in the early phases of the dimension stone construction technique.  相似文献   
4.
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   
5.
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   
6.
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   
7.
Architecture in early modern Sardinia is characterized by a strong continuity with previous practices. In the second half of the 16th century, new models join the Gothic building tradition, linked in particular to trends in military engineering and Classicism of the Catholic Counter-Reformation. The Jesuit church in Sassari offers an interesting example of the intertwining of these architectural modes, which originated with a sudden change of leadership at the site. Giovan Maria Bernardoni, an Italian Jesuit architect, initially modeled the church after the Gesù in Rome, and it was partially built under his direction. After his departure from Sardinia, local master builders finished the construction, following the Gothic tradition and possibly some external influences. This article analyzes the church, particularly focusing on the challenges presented by its articulated vaulting system completed between 1587 and 1609.  相似文献   
8.
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   
9.
We present the results of a multi‐method archaeometric study concerning the architectural elements reused in Monte Sorbo church (Sarsina, central Italy) between the eighth and ninth centuries AD . The provenance study has focused on classical marbles and stones, which clearly do not originate from the local Apennine geological formations and are thought to come from extra‐regional sources. A large fraction of the tested marbles is from Asia Minor, coming from both the Proconnesian district on Marmara Island and, probably, the Hasançavuslar site near Ephesus (Greco scritto). Of the four remaining marbles investigated, one is from the Carrara district and three are from different Greek quarrying areas, such as Mount Pentelikon (Athens) and the Thasos and Paros islands. The data also highlight the reuse of decorated gravestones made of Pietra di Aurisina as architectonic elements. This limestone is a fossiliferous carbonate stone outcropping in the Trieste Karst region (north‐eastern Italy), which was exploited by both the Romans and the Byzantines. The assignment of all of the columns of the central nave to the same source area provides an argument in favour of their provenance from a single monument, which was probably located in Sarsina or Ravenna, with the ‘colourful taste’ that is typical of the late Antonine and Severian periods.  相似文献   
10.
Northeastern China is one of the centers of early development of agriculture and sedentary life, as well as of the subsequent development of social complexity and distinct cultural attributes. While the outlines of this trajectory are clear, its important details are still elusive. Like all other regions of northern China, there is little data on the all-important transition from nomad hunter-gatherers to sedentary agriculturalists. The Fuxin Regional Survey was designed as the first step in accumulating new data and addressing the geographic and ecological contexts of these socioeconomic processes. Among the most remarkable results of this survey is the identification of early ceramics, which possibly predate the transition to agriculture. The systematic collection and analysis of stone tools was done in a way never before done in this region. Analysis of our findings, using GIS and other methods, sheds new light on the local trajectory of human adaptation in this area.  相似文献   
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