Dome of the Basilica of Santa Maria Degli Angeli in Assisi: Static and Dynamic Assessment

This study presents the results of the static and dynamic assessment of the dome of the Basilica of Santa Maria degli Angeli in Assisi, designed by Galeazzo Alessi. The first section is devoted to an overview of the masonry domes designed by the Italian architect and focuses on the structural solutions adopted in the several cases described to better understand Alessi’s designing skills. In the second part, the drum-dome system is analyzed in order to attain a structural assessment. The static assessment is performed by means of limit analysis and finite element model approaches with non-linear mechanical behavior. The obtained results are consistent with the detected crack pattern and confirm the suitability of the reinforcement steel rings applied to the drum. The seismic assessment has been performed by response spectrum analysis. Due to the lack of specific information, a probabilistic approach for the material mechanical properties was used. The results obtained highlight an adequate seismic response of the structure that can be attributed to the dynamic properties of the slender drum-dome system. This finding justifies the good performance of the structure during the seismic events of 1832 and 1997.     

宁波保国寺大殿风振性能研究

为了更科学地保护我国传统木构建筑,需要研究我国江南地区传统木构建筑的风振性能,为此,以江南地区最古老、保存最完整的佛教木构建筑——保国寺大殿的主殿为例进行风振性能研究。首先基于三维激光扫描获得的真实可靠的保国寺大殿的几何信息,采用SAP2000有限元软件建立主殿的有限元模型,并进行动力特性分析。再利用MATLAB软件编写脉动风速时程,并将风压作用于有限元模型上分析,得到主殿的风振响应。得到结构模态、位移时程曲线、位移谱曲线、加速度响应,并对时程位移风振系数和规范风振系数进行对比。结构的振动响应主要由前三阶振型控制,在强风荷载作用下,最容易出现的变形就是南北向振动、东西向振动和扭转振动;各个典型节点的最大位移均在侧向位移容许值内;迎风面阑额中心位移最大、屋面上半部次之、屋面下半部及檐柱柱头最小;主殿相连的两个部分的加速度相差较多,屋面和屋身的连接节点应成为日后保国寺大殿的保护重点;时程风振系数变化与规范风振系数的变化规律不同是因为结构横向刚度分布不均匀;时程风振系数是规范风振系数的1.2~1.4倍,这是由于按照规范计算风振系数的过程中只考虑了第一阶振型的影响而忽略其他所有振型的结果;规范风振系数的计算只适用于形状、质量沿高度不变的高耸结构,不适用于类似本研究中的低矮木构传统房屋结构。     

Simulation of Shake Table Tests on Out-of-Plane Masonry Buildings. Part (V): Discrete Element Approach

ABSTRACT

The analysis of the shaking table test of a 3-wall stone masonry structure performed with a discrete element model is presented. The numerical model, created with the code 3DEC, employed a rigid block representation and a Mohr-Coulomb joint model. Joint stiffness calibration to match the experimental natural frequencies is discussed, as well as the boundary conditions to simulate the shake table. Comparisons are made with the measured displacements at key locations, and the modes of deformation and fracture of the walls. The DEM model was able to reproduce important features of the shaking table tests. The experimental deformation and near collapse patterns were clearly identifiable in the numerical simulations, which produced displacements within the observed orders of magnitude, for the various levels of excitation.     

Cultural Site Formation Processes in Maritime Archaeology: Disaster Response, Salvage and Muckelroy 30 Years on

Thirty years after Muckelroy's seminal 1976 paper on shipwreck site formation, research on the cultural processes which contribute to the creation and modification of shipwrecks remains limited. It is proposed that by adopting a process-oriented framework, we can integrate and synthesize the documentary, oral and archaeological evidence of human response to shipwreck into a structure which parallels the physical progress of the disaster. Possible cultural responses to shipwreck are considered, from pre-voyage planning through to post-impact salvage, including physical correlations potentially visible in the archaeological record.
© 2006 The Author     

Reflections on Recent Cognitive Behavioural Research with an Emphasis on Research in the United States of America

In this paper, I reflect on some of the more recent trends in cognitive behavioural research that includes work by geographers. In particular, I examine recent work on spatial decision‐making in the context of Intelligent Transportation Systems and Smart Environments, spatial cognition and human wayfinding behaviour, contributions to Geographic Information Science, and embellishing activity approaches that focus on episodic human behaviours. The paper emphasises that much of this research is multidisciplinary and that much of it is published in non‐geography journals. The paper concludes with some thoughts about future research directions, together with comments on how this research may influence the teaching and use of geographic concepts. ACRONYMS ATISAdvanced Traveller Information Systems CPMComputational Process Models CRTCathode Ray Tube DLDigital Library GISGeographic Information System GIScGeographic Information Science GPSGlobal Positioning Systems ITSIntelligent Transportation Systems UCSBUniversity of California Santa Barbara VEVirtual Environments     

回顾与展望:社会史视野下的中国蝗灾史研究

近二十多年来,社会史新颖的视角使史学研究趋向丰富和深入,但这并未引起蝗灾史研究者的重视。本文以蝗灾与社会的互动关系为线索,在梳理蝗灾史研究的发展脉络的基础上,对目前的研究不足提出几点看法,并就蝗灾史研究中应该引入新的视角和方法、挖掘新的历史资料等方面做出展望。     

区域产业结构演变的城市化响应机理研究

区域产业结构演变城市化响应的研究作为地理学新的研究领域,已经越来越成为理论界和学术界研究的热点。本文对产业结构演变城市化响应的内涵进行了界定,从产业结构演变城市化响应过程、强度、形态、机制以及变化趋势等几个方面系统分析了区域产业结构演变的城市化响应机理,并建立起理论体系,以期为区域产业结构与城市化的研究开拓新的研究视角。     

克洛马事件与台湾当局的应对

1939年,日本侵占南沙群岛,改名为新南群岛,划归台湾总督府管辖。1946年12月12日,中国军队登陆太平岛,竖立界碑,重申对南沙群岛的主权。1950年,台湾当局自太平岛撤出军队。1951年,《旧金山和约》签署,规定"日本放弃对南沙群岛及西沙群岛之一切权利、权利根据与要求"。这改变不了南沙群岛、西沙群岛属于中国领土一部分的事实。1956年,菲律宾商人克洛马代表"人道王国",占据了南沙群岛的几座岛礁。其属于个人行为,不具有官方身份。台湾当局立即要求菲律宾政府承认南沙群岛属于中国领土,制止克洛马的非法行为。同时,台湾当局派海军巡航南沙群岛,在太平岛驻军,劝离克洛马探险队,来巩固对南沙群岛的司法管辖权。美国政府要求台湾当局通过和平谈判,避免流血冲突。不甘心失败,克洛马拟要求联合国仲裁南沙群岛争端。     

Ivane Tarkhnishvili (Ivan Tarchanoff) and His Links With Poland

According to some sources, Professor Ivan Tarchanoff (Ivane Tarkhanishvili) died in Saint Petersburg in 1908. In fact, he died in Poland in his house in Nawojowa Góra, a suburb of Krzeszowice, not far from Kraków. A student and later assistant of Tarchanoff in Saint Petersburg, Napoleon Cybulski, was then professor of physiology at the Jagiellonian University in Kraków and its rector and deputy rector. It is hardly known that Tarchanoff spent the last three years of his life mainly in Galicia, at that time part of the Austro-Hungarian Empire. There, near Kraków, he built himself a house and it was in Galicia (in Kraków and Lemberg [Polish Lwów, today Lviv]) that he worked on some of his last papers. The strong link between Tarchanoff and Polish physiology is not sufficiently well known and deserves to be recognized.     

青海原生态民歌反映论

原生态民歌热唱现象,反映出当今社会大众的心理和文化倾向,引起了全社会对民族口授文化遗产更多的重视。分析并关注这些大众心理和文化倾向,不仅有利于提高全社会对青海非物质文化遗产——民歌的更多关注,也为从民歌角度认识社会提供了一条有效的途径。