宝鸡眉县出土27件窑藏青铜器锈蚀特征及成分的分析研究

为了研究刚出土的青铜器在新的环境中的发展变化情况,在宝鸡眉县27件国宝级西周窖藏青铜器出土一年半后,对这批器物出土前后的锈蚀类型及特征进行了分析和描述,并对每一器物的锈蚀产物进行了系统检测分析。结果显示,这批青铜器腐蚀类型主要为封闭环境中的大气腐蚀,主要产物为碳酸盐和氧化物。但同时在其中一个器物上发现了氯化物类有害锈成分,分析认为,出土前后环境的变化是有害锈得以产生和发展的根本原因。     

A Hybrid Masonry and Steel Mirror-Type Vault with Lunettes: Survey and Structural Analysis

ABSTRACT

The structural analysis of a mirror-type vault, consisting of a single- or double-curvature perimeter and a nearly flat part, is carried out. The vault is similar to a number of hybrid iron (or steel) and masonry vaults built between the late 19th century and the early 20th century to span large halls. The numerical analyses were preceded by an accurate geometrical survey and mechanical tests aimed at evaluating the properties of the materials. Thermography allowed the complex brick pattern of the vault to be detected. The influence of rib-walls (frenelli) and the material anisotropy on the stress and deformation of the vault is discussed. Eventually, attention is focused on one of the segmental vaults in the central part of the structure: it is found that the stress can be safely estimated by assuming its boundary to be fixed.     

Experimental characterization of the constitutive materials composing an old masonry vaulted tunnel of the Paris subway system

A significant proportion of the Paris metro tunnels comprise a masonry vault built out of stone blocks and mortar joints, and sidewalls and slabs made of unreinforced concrete. In order to provide the necessary data for future structural evaluation, an extensive laboratory testing programme has been conducted to characterize the materials of the tunnel separately, i.e., mortar, stone, and concrete. The tests, carried out on specimens taken from cores extracted from a 1930s tunnel, enabled to determine the mechanical properties, including direct tensile, shear strength, and mode I fracture energy, as well as the properties of the stone-mortar interface. Results show that the masonry mortar joints could reach 10 cm in width, and that blocks of stone varied in composition and porosity, thus producing a wide range of mechanical properties. The concrete was composed of large-sized aggregates and showed low stiffness and strength. Based on these experimental results, ratios between mechanical characteristics are hereby proposed. Perspectives on the use of this experimental data in a finite element model are then discussed.     

Design and Analysis of Cross Vaults Along History

The history of cross vaults began almost 2,000 years ago with a widespread use during the Middle Ages and Renaissance, becoming nowadays one of the most diffused and fascinating structural typologies of the European building cultural heritage. However, conversely to the undeniable excellence achieved by the ancient masons, the structural behavior of these elements is still at the center of the scientific debate. In this regard, with the aim of reviewing the knowledge on this subject as a concise and valuable support for researchers involved in conservation of historical buildings, with a focus on design rules and structural analysis, the present study firstly introduces the cross vaults from a historical perspective, by describing the evolution of the main geometrical shapes together with basic practical rules used to size them. Then, the article deals with the subsequent advancements in structural analysis methods of vaults, until the development of modern limit analysis.     

Geometry,Construction and Structural Analysis of the Crossed-Arch Vault of the Chapel of Villaviciosa,in the Mosque of Córdoba

The vault of Villaviciosa is one of the oldest existing examples of a true ribbed vault, and is the first of the crossed-arch type. Although its perfection suggests earlier trials, none has been found so far. It predates the oldest Romanesque ribbed vaults by more than a century. Notwithstanding its importance, no construction and structural study has ever been done; neither has an accurate survey been published. The purpose of this article is to fill this gap in the history of vault construction. A detailed survey has been made, providing the first accurate drawings of the vault. A close inspection of the extrados, completed with a visual inspection of interior damages, has allowed ascertaining the main construction features. With the geometry and the material data a structural analysis has been carried out. This analysis explains the fundamental structural behavior of the vault and throws new light into some historical issues; for example, it leads to discarding the widespread belief that the ribs are decorative: they are supporting the weight of the vault.     

Experimental Studies on Buried Barrel Vaults

The paper concerns an interaction problem between soil and masonry vaults in historic buildings. A particular emphasis was placed on the influence of finishing method of vaults extrados and fill material properties on the behavior of masonry vaults. The results of experimental studies on barrel vaults with and without backfill are presented. During the experiments three finishing methods of vaults extrados and three fill materials were investigated. The results of the experiments show that the presence of backfill and type of vaults extrados finish affect the behavior and load-carrying capacity of tested elements. Moreover, tests were performed on vaults without fill for comparative purposes. The comparison of experimental results obtained for specimens with and without fill shows that the presence of backfill in vault haunches modifies the failure mechanism and increases load capacity of the analysed models. The presented results confirm the importance of backfill as a structural element of vaulted structures.     

荆州文庙大成殿维修勘察测绘报告

荆州文庙大成殿为清代中期一座建筑。本文通过对大成殿现场勘察测绘,并结合有关资料阐述了荆州文庙兴衰的历史过程,同时对大成殿建筑结构的测绘分析,挖掘出这座古老建筑独特风貌和别具一格的建筑工艺,反映我国古代劳动人民无穷智慧和伟大的创造力,从而使我们不遗余力地保护这座建筑,使之千秋万代。     

Remarks on British and Roman Urns

The parish church of St Andrew at Irnham in Lincolnshire possesses a richly carved stone monument dating to around 1340 which bears the arms of Sir Geoffrey and Agnes Luttrell, associated with the celebrated Luttrell Psalter. The form, imagery and function of this monument are problematical and are discussed first in order to create a context for an unusual aspect of its architecture, namely that its inner vault is a miniature copy, unique in this part of England, of the main vault of the choir of Wells Cathedral, a so-called ‘net’ vault. Amongst the reasons for such an unusual citation may be the existence in Somerset, in the diocese of Wells, of one branch of the Luttrell family at the time this monument was raised.     

The 14th-Century Rebuilding of the Collegiate Church of St Mary’s,Warwick

The 14th-century rebuilding of the collegiate church of St Mary’s by the earls of Warwick has received surprisingly little scholarly consideration, despite the status of its patrons and the distinctiveness of its architecture. This article uses drawings of the building before the fire of 1694, which destroyed its west end, together with the college’s extensive cartulary and other records, to reconstruct the 14th-century church. From this a timeline for the construction of the church is proposed. Regional, national and international stylistic precedents and antecedents are explored and used to test the validity of the ‘centre/periphery’ model of architectural change. The article concludes with a brief discussion of methodological insights drawn from the analysis.     

The Groin Vaults of St. John Hospital in Jerusalem: An Experimental Analysis on a Scale Model

The St. John Hospital is part of a larger complex of buildings known as the Hospitallers Quarter, located south of the Holy Sepulchre in Jerusalem. At present, the hospital looks like an irregular volume both in height and in plan; it is covered by ten groin vaults resting on very stocky pillars. Each vault is formed by intersecting double curvature surfaces. In order to verify the effectiveness of continuous carbon fiber reinforced polymer sheets reinforcement, bonded at the extrados of vaults, laboratory tests were carried out on a 1:5 scale model, built with materials and construction techniques similar to those of the real building. Experimental tests were performed on the unstrengthened and strengthened vault. The experimental results shown that the strengthening system is able to increase the collapse load of the vault, without substantial variation of the initial stiffness.