川杨河大型古木船室外冷冻脱水处理

1979年底上海浦东川杨河发掘工地出土了一艘古代木船.上海博物馆文物保护科学实验室对这艘大型古木船进行了室外冷冻阴干处理。采用的是利用自然气候冷冻阴干的方法.原理是将被处理物件保持在冷冻状态.利用温差产生的蒸汽压差进行升华干燥.经过十年的考验,证明这种方法对大型浸饱水木的脱水保护是切实可行的.工艺简单.干燥时间短,费用低廉,解决了国内外在处理大型浸饱水木文物方面的一些问题.     

元代蓬莱古船加固技术

介绍了在山东省蓬莱市登州港发掘的蓬莱古船在保护过程中采取的“■料”修复技术、聚醋酸乙烯脂丙酮溶液喷涂船全加固技术以及生桐油喷涂船体保护技术。     

A Royal Boat Burial and Watercraft Tableau of Egypt's 12th Dynasty (c.1850 BCE) at South Abydos

Excavations at Abydos, Egypt, during 2014–2016 have revealed the remains of a boat burial dating to the reign of Senwosret III (c.1850 BCE). The boat burial occurred inside a specially prepared, subterranean vaulted building. Surviving elements of planking appear to derive from a nearly 20 m‐long boat that was buried intact but later dismantled for reuse of the wood. The vessel may belong to a group of royal funerary boats associated with the nearby tomb of Senwosret III. Incised on to the interior walls of the boat building is an extensive tableau including 120 surviving drawings of pharaonic watercraft. A unique deposit of pottery vessels was found associated with the ceremonial burial of this royal boat.     

The Thaikkal-Kadakkarappally Boat: an Archaeological Example of Medieval Shipbuilding in the Western Indian Ocean

Recent excavations at Kadakkarappally in Kerala, south-west India, have unearthed the remains of an iron-fastened boat, believed to predate the earliest known records for the use of iron in South Asian boatbuilding. The design departs significantly from the traditional view of Indian watercraft, although the use of locally available timber and the suitability of the design for use in the backwaters that characterise the region suggest that it was built and used in India. This is the first excavation of its type to take place in Kerala and contradicts the belief, widely held in Kerala, that the survival of organic remains has been negated by the tropical climate of the region.
© 2004 The Nautical Archaeology Society     

FATIGUE ANALYSIS OF MOMENT RESISTING STEEL FRAMES

A procedure for the fatigue assessment of steel building structures subjected to earthquakes is presented. The procedure constitutes an extension of the present, high-cycle, fatigue assessment to cases of low-cycle fatigue. It may serve as a basis for the introduction of a fatigue limit state in the earthquake design of steel structures. It may be also used for the damage assessment of existing steel buildings subjected to past earthquakes. By means of parametric studies, the effects of various parameters on the fatigue susceptibility of several moment resisting steel frames are studied. The influence of a number of parameters such as the type of ground motion, type of structural typology, local fatigue behaviour, overall frame design and semi-rigidity of joints on the susceptibility to damage are investigated.     

DISPLACEMENT-BASED SEISMIC ASSESSMENT OF REINFORCED CONCRETE BUILDINGS

Abstract

Seismic assessment of existing reinforced concrete frame and shear wall buildings is discussed. Building on an earlier preliminary assessment procedure incorporating aspects of capacity design into a systems approach for assessment, suggestions are made towards a displacement-based, rather than forced-based, approach to determining available seismic capacity. Based on results from recent experimental programs, procedures are proposed for assessing member strength including column and beam-column joint shear-strength, that result in less conservative estimates of performance than would result from application of existing code rules.     

ESTIMATION OF NEAR-SOURCE GROUND MOTION AND SEISMIC BEHAVIOUR OF RC FRAMED STRUCTURES DAMAGED BY THE 1999 ATHENS EARTHQUAKE

On September 7, 1999 an earthquake with magnitude M _W =5.9 occurred close to the city of Athens in Greece. More than 80 buildings collapsed, about 150 deaths and hundreds of injuries were reported. Soon after the event a damage investigation was carried out by two of the authors in the most heavily struck areas. The most serious damages were observed in the northern suburbs of Athens, where reinforced concrete frames and masonry buildings represent the prevalent construction systems. The hysteretic energy demands imposed on RC buildings should have been rather severe considering the structural systems characteristics and the inadequate construction details. However, over-strengths, redundancy and especially the presence of infill walls, provided a significant increase of the seismic capacity and contributed to the survival of many buildings.

The objective of the present work is to reproduce and analyse the response of typical RC frames subjected to the 1999 Athens earthquake in areas where the observed damage was particularly severe but no recordings of the ground motion were available. After a general overview of the seismotectonic environment, seismological data, observed macro-seismic intensities, structural typologies and observed building behaviour, an attempt is made to identify representative excitations in the meizoseismal area. Specifically, the required accelerograms are obtained by modifying available records so as to reproduce a given global energy content and to be consistent with the observed damage. To study the seismic response of RC models, the obtained accelerograms are used to perform nonlinear dynamic analyses.     

试论古建筑木构架类型在历史演进中的关系

文章对现有的理论模式进行反思, 对中国古建筑木构架的几种类型的在历史演进中的关系提出了假说: 从干栏式到地面的穿斗式是木构架自然的发展序列, 具有普遍性。官式建筑的产生和秦汉以来高等级建筑采用井干式与多层木楼阁有关, 并受到穿斗式的影响。抬梁式是官式建筑发展的结果并反过来影响了南北方的民间建筑。     

Sewn Boats of Southeast Asia: the stitched‐plank and lashed‐lug tradition

This article updates research into the sewn‐boat traditions of Southeast Asia with recent finds that provide evidence of the transition from stitched planks with lashed‐lug frames to planks fastened with dowels and locked dowels alongside lashed‐lug frames. The differences between Southeast Asian, East Asian, and Indo‐Arabic boatbuilding are discussed and the meaning of anomalies, such as the Maldivian dhonis, examined. Considering the known history of trade and exchange throughout the South China Sea and the Indian Ocean, the lack of hybridization between boatbuilding traditions is noted.     

Designing the 9th-Century-AD Vessel from Bozburun, Turkey

During the study of the 9th-century-AD vessel from Bozburun, Turkey, this author applied Richard Steffy's methodology which emphasizes the comprehensive deconstruction and step-by-step re-assembly of a vessel. This methodology, in turn, illuminated how the Bozburun ship was assembled and designed, and how this design process created particular components of the hull. This article discusses this design process, and how by understanding it we may also understand more about the people who made the Bozburun vessel.
© 2009 The Author     

SEISMIC ENERGY DEMAND IN STEEL MOMENT FRAMES

The present paper investigates the seismic energy demand in steel moment-resisting frames. The frames, with 3, 6 and 10 storeys, and 4 and 8 spans, are designed according to current seismic code provisions. The energy response (energy quantities and their distributions) in the frames subjected to an ensemble of six earthquake ground motions recorded on different soil conditions, is investigated by nonlinear time history analysis. The study concludes that (1) the results of energy response can be developed into a rational method of seismic evaluation and design for steel moment-resisting frames; (2) the energy concept based on the single-degree-of-freedom has limitations when extended to the realistic structural system for design purposes; and (3) it is necessary to develop the energy-based approach for seismic evaluation and design based on the seismic response of a realistic multi-degree-of-freedom structural system.     

NON-LINEAR SEISMIC RESPONSE OF ECS DESIGNED RC BUILDING STRUCTURES

In this paper, results of an analytical study on the non-linear dynamic behaviour of reinforced concrete buildings designed according to modern European Codes (Eurocode 8) are presented. An investigation of the seismic performance of 8-storey regular and irregular buildings is carried out. The study is aimed at evaluating their seismic structural performance with a focus on the influence of several design parameters used in the code affecting non-linear response. Towards this aim, use is made of a suite of spectrum-compatible artificial accelerograms. It is concluded that EC8 provisions, although correct in principle, are conservative, at least for the structures and input motions considered, in view of the very low predicted damage levels observed in most cases.     

始终把思想建设放在党的建设首位

把思想建设摆在党的建设首位,是中国共产党的历史选择和重要优势,是党提高创造力、凝聚力和战斗力的重要经验,是党领导革命、建设和改革伟大事业的理论支撑。中国共产党始终坚持思想建党的原则,坚持以马克思主义及其中国化理论成果武装全党并用以指导实践,使之成为全党和全国人民团结奋斗的共同思想基础。同时,强调思想建设要正确对待党内思想斗争、认真解决思想领域存在的突出问题。     

Designing the 11th-century-AD vessel from Serçe Limanı, Turkey

A previous article investigated the methods used to design the 9th-century vessel from Bozburun, Turkey, and a basic methodology emerged which combined Richard Steffy's emphasis on the comprehensive deconstruction of a hull with the segregation of hull-construction into the phases of conception, design and assembly. This article tests this methodology by applying it to the 11th-century craft from Serçe Limanı, a vessel studied and reconstructed by Steffy. It discusses the resulting design-method, the similarities between this method and that used on the Bozburun vessel, and how we gain insight into changes in the maritime community which built these ships.
© 2010 The Author