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91.
Research conducted by Newell et al. (1990) has lead to propose that during the Mesolithic, the Upper Danube region was inhabited by a “Fish Teeth Band”, characterized by the use of carp fish teeth and exogenous fossil shells as ornaments. However, technological data on these personal ornaments drastically lacked and especially for the fish teeth associated to the Mesolithic burial of Hohlenstein-Stadel that remained completely undescribed until now. The aim of this paper is to establish how the carp teeth from Hohlenstein-Stadel were modified and worn before being deposited in the burial. High-resolution microscopic analysis identifies use-wear traces and a red compound adhering to the surface of the teeth. Structural and elemental analysis of the residue combining light and scanning electron microscopy, infrared spectroscopy, and Raman analysis identify a suspension technique that uses an adhesive composed of an organic binder mixed with charcoal and minerals including hematite, dolomite, and quartz. Ethnological inquiry reveals that this system of suspension, commonly used in traditional societies, is for the first time documented, at Hohlenstein-Stadel, in an archaeological context.  相似文献   
92.
Past earthquakes have shown the high vulnerability of existing masonry buildings, particularly to out-of-plane local collapse mechanisms. Such mechanisms can be prevented if façades are restrained by tie rods improving the connections to perpendiculars walls. Whereas in the past only static models have been proposed, herein the nonlinear equation of motion of a monolithic wall restrained by a tie rod is presented. The façade, resting on a foundation and adjacent to transverse walls, rotates only around one base pivot and has one degree of freedom. Its thickness is explicitly accounted for and the tie rod is modeled as a linear elastic—perfectly plastic spring, with limited displacement capacity. The model is used to investigate the response to variations of wall geometry (height/thickness ratio, thickness), tie rod features (vertical position, length, prestress level), and material characteristics (elastic modulus, ultimate elongation, yield strength) typical of historical iron. The most relevant parameter is the steel strength, whereas other characteristics play minor roles allowing to recommend reduced values for pre-tensioning forces. The force-based procedure customary in Italy for tie design is reasonably safe and involves protection also against collapse, although probably not enough as desirable.  相似文献   
93.
A simplified approach for analyzing the nonlinear response of masonry buildings, based on the equivalent frame modeling procedure and on the nonlinear equivalent static analyses, is presented. A nonlinear beam finite element (FE) is formulated in the framework of a force-based approach, where the stress fields are expanded along the beam local axis, and introduced in a global displacement-based FE code. In order to model the nonlinear constitutive response of the masonry material, the lumped hinge approach is adopted and both flexural and shear plastic hinges are located at the two end nodes of the beam. A classical elastic-plastic constitutive relationship describes the nonlinear response of the hinges, the evolution of the plastic variables being governed by the Kuhn-Tucker and consistency conditions. An efficient element state determination procedure is implemented, which condenses the local deformation residual into the global residual vector, thus avoiding the need to perform the inner loops for computing the element nonlinear response. The comparison with some relevant experimental and real full-scale masonry walls is presented, obtaining a very good agreement with the available results, both in terms of global pushover curves and damage distributions.  相似文献   
94.
In masonry materials, the superficial decay is a widespread problem. Aggressive environmental agents such as moisture and salts trigger the damage by propagating through the material capillary pores. Although several studies have been carried out on salt crystallization and their damaging effects, additional research effort is required to better investigate this phenomenon on real cases and real weathering conditions. To this purpose, testing and monitoring tools capable of following degradation process since the early beginning are necessary. Repeated visual inspections are commonly used to monitor the superficial decay, but this technique is subjective and thus not capable of providing any quantitative information. In this work, an experimental campaign, carried out in Bologna, Italy, is presented. A two-header brick wall, one main face unplastered and one plastered, was stored outdoors and exposed to weathering over two summers. Before the start of the second aging season, moisture and salt capillary rise was simulated by low-concentrated sodium chloride solution (0.1% -wt). The aim was to favor solution evaporation and salt crystallization and to provoke material damage. The degradation process was monitored based on a contactless, rapid and accurate image diagnostic technique. In particular, high-resolution laser scanning by triangulation technique was adopted. Three-dimensional data acquisition was repeated at the end of both seasons. The proposed procedure successfully extracted quantitative information approximately areas of material spalling and detachment even in the initial phases of decay.  相似文献   
95.
ABSTRACT

Out-of-plane response of unreinforced masonry elements is frequently the most critical aspect of the seismic performance of existing masonry buildings. The response of such elements is usually governed by equilibrium rather than strength. Hence, it is customary to resort to rigid-body models, accounting for possible rotations, and/or sliding. However, the results of such analyses depend on the initial choice of the mechanism. In this article, the shaking-table experiments on a brick-masonry specimen, and on a stone-masonry specimen have been modeled by resorting to a combined finite-discrete element strategy. Despite the coarse discretization of both discrete and finite elements, the three-dimensional models are able to capture the experimentally observed multi-degree-of-freedom mechanisms, without any a priori assumption on the mechanism. A sensitivity analysis is carried out, addressing eight different parameters. The identification of the mechanism is sufficiently robust, but the assessment of its activation and failure is best done by combining the finite-discrete element model with a simplified model of the recognised mechanism.  相似文献   
96.
This study shows the results of a multidisciplinary collaboration between the University of Calabria (Italy) and the National Autonomous University of Mexico (UNAM), about the compositional characterization of some mortars taken from Hagia Sophia in Istanbul (Turkey), one of the most important buildings in antiquity. Twenty samples of joint mortars were analysed by micro-chemical analyses (SEM-EDS), X-ray powder diffraction (XRPD), optical microscopy (OM) and transmission electron microscopy (TEM). The compositional study allowed us to define, with more detail, the construction phases of the fifth, sixth and tenth century. The petrographic analysis in thin section by optical microscopy showed four typologies of sands, used as aggregate, with specific compositional features. SEM-EDS analyses and TEM observations of the binder around the ceramic fragments of the aggregate showed the presence of different morphologies of single C-S-H compounds.  相似文献   
97.
The presence of transhipment services in a region has previously been analyzed relative to ports and shippers with no consideration to the geographical factors of the sea basin serving the region. We hypothesize that attributes related to basin morphology also should be considered, as the processes involved in the maritime container freight market are comparable to processes in other transport markets. We show that transhipment services are relevant in those regions with closed sea basins. This article addresses the following issues: the traditional analytic methods used to determine, directly or indirectly, the presence of transhipment services; the role of transhipment in some geographic regions by estimating the rate of transhipment relative to throughput for each region; and the estimation of a statistical model that can determine the presence of transhipment by means of aggregate variables related to the morphology of a sea basin serving each region and to the socioeconomic characteristics of the region served. La presencia de servicios de transbordo en una región ha sido analizada en relación a los puertos y cargadores, sin considerar los factores geográficos de las cuencas marítimas al servicio de una región. Nuestra hipótesis es que los atributos relacionados a la morfología de las cuencas también deberían tomarse en cuenta, ya que los procesos involucrados en el mercado de contenedores de carga marítima son comparables a los procesos de otros mercados de transporte. Mostramos que los servicios de transbordo son relevantes en aquellas regiones con cuencas marítimas cerradas. El presente artículo aborda los siguientes temas: los métodos analíticos tradicionales generalmente usados para determinar, directa o indirectamente, la presencia de servicios de transbordo; el rol del transbordo en algunas regiones geográficas, a partir de la estimación de las tasas de transbordo relativas a su rendimiento (throughput) en cada región; y la estimación de un modelo estadístico que pueda determinar la presencia de transbordo a partir de variables agregadas relacionadas a la morfología de la cuenca marítima al servicio de cada región, y a las características socioeconómicas de cada región. 区域海运转运服务的分析已经将港口和航运商纳入研究范畴,但忽视了区域海洋盆地地理因素的影响。由于参与海运集装箱货运市场的过程与其他运输市场的过程具有可比性,因而本文认为和海盆形态有关的属性也应考虑在内。研究结果显示,转运服务与那些靠近海盆的区域具有相关性。本文将重点对以下问题进行阐述:过去经常用来直接或间接判断转运服务的传统分析方法;通过估计一个地区相对于自身吞吐量的转运率来判断部分地理区域在转运服务中的角色;通过区域海盆形态和社会经济属性相关的综合变量,构建能够判别转运服务的统计模型.  相似文献   
98.
99.
In this paper I propose a novel integration of inductive predictive modelling and ethnoarchaeology. The case study concerns seasonal upland pastoral settlement patterns in the eastern Italian Alps. A sample of modern pastoral sites has been selected, and their relationships with environmental variables have been analyzed in order to create a model to predict the location of archaeological upland pastoral sites. The model has been tested with modern and archaeological control samples. It has proved to be useful for predicting the location of specific site categories. Ethnoarchaeological fieldwork has been carried out in the same alpine sample area, which has enhanced the interpretative potential of the proposed model, suggesting that the spatial of the analyzed sites could well be related to their dairying function. The creation of ethnoarchaeological locational models with a predictive potential may be very important not only in helping to tackle some theoretical and methodological problems in predictive modelling, but also in enhancing the importance of ethnoarchaeology in landscape archaeology projects.  相似文献   
100.
The sedimentary sequence at Diepkloof Rock Shelter formed through a complex interaction of depositional and post-depositional processes and was variously influenced by biogenic, geogenic, and anthropogenic agents. Here, we present the results of a micromorphological study of the sediments at Diepkloof, focusing in particular on the numerous anthropogenic inputs and modifications recorded within the sequence. By applying the microfacies concept, we were able to identify hearth burning and maintenance, bedding construction and burning, and surface modification by trampling as major processes that contributed to the formation of the site. The human activities recorded within the sediments show a marked change throughout the sequence, implying a shift in the use of the site over time. The present study also provides a context for evaluating other classes of artifacts and data collected from the site.  相似文献   
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