Impact Stiffness of the Contact-Element Models for the Pounding Analysis of Highway Bridges: Experimental Evaluation

For the requirement of pounding analysis of highway bridges, how to properly choose the impact stiffness has become a primary issue for an achieving accurate result. This article presents an evaluation test of the impact stiffness of four types of contact-element models based on the shaking table test results of a steel highway bridge model. The analytical results indicate that the theoretical impact parameters are significantly larger than the identified values because the assumptions for deriving those models cannot match the actual impact conditions. The possible reasons causing those differences are discussed at the end of this study.     

Macro-Modeling of Reinforced Concrete Structural Walls: State-of-the-Art

During the past decades, various analytical macroscopic models of structural walls have been developed for simulating the seismic behavior of reinforced concrete (RC) walls. Due to the inherently complicated characteristics of RC walls, macroscopic models that can capture all the important response characteristics with good accuracy and applicability are very challenging to establish. A thorough review of the four main types of mathematical macro models of RC walls, i.e., the vertical-line-element-model, the 2-D shear panel element model, the equivalent truss model and the fiber-based model, is presented to discuss the methodology behind each model and examine the corresponding merits and disadvantages. Suggestions are also made for the further research of the macro modeling of structural walls.     

Firing temperature of a clay core sample in a bronze tripod from Daxinzhuang Site in China using TL techniques

In this paper, we studied the thermal history of a clay core sample from one leg of a bronze tripod unearthed at Daxinzhuang Site, Shandong, China. The properties of the luminescence signals of quartz depend on the maximum temperature at which the quartz was annealed in the past. We examined the feasibility of measuring the thermoluminescence (TL) sensitivity change of quartz for exploring the firing temperature of archaeological materials. The sensitization factor of the 110°C TL peak (S₂/S₁) and the ratio of the 210°C TL peak to the 110°C TL peak at different annealing temperatures were utilized to unveil the firing temperature in the clay core sample. The firing temperature of the clay core sample was approximately 700°C–800°C, proving the clay core has been fired. This result proved that the clay core has been fired by human agencies and indicated on the temperature of the clay core in drying and firing given by the foundry workers before the actual casting step.     

领略贵州古村落风韵

引言：最近,受清华大学陈志华、李秋香两教授的邀请,我参与《中华古村落》大系的编撰工作。每省一卷,我承担贵州卷。每卷收录20个古村落,每个村落3000字,20幅照片。另外,写一篇一万字的《分卷序》。在此基础上,我撰写了《领略贵州古村落风韵》一文,主要介绍贵州古村落的自然环境、历史流年、地域特点、民族特色、美丽外观、鲜明个性、丰富的内涵等等。     

Comment on ‘Did China Import Metals from Africa in the Bronze Age?’

Lead isotope compositions provide a direct means of assessing provenance. The lead contents in bronzes cannot be used to argue against lead isotopes. Any claim for the origin of the source material for the origin of Yin‐Shang bronzes must satisfy the measured lead isotope compositions. Thus far, only southern African sources are found to meet this criteria.     

城坝遗址M45出土一组乐器的分析研究

本文对四川渠县城坝遗址出土的錞于、钲、钟一组青铜乐器做了相关分析,研究发现:这组乐器属铜锡铅三元合金,錞于、钟含有微量砷;均采用范铸法分批、分部件浇铸而成,各部位合金比例不尽相同,錞于的合金比例差别较大。通过微痕信息观察,器身上的部分巴蜀符号为刻划成型而非铸造;器物用途可能仅为陪葬品而非实用器。     

土默特平原聚落分布形态演变及其驱动因素分析(1934—2019)

选取土默特平原1934、1982和2019年的聚落人口数据,运用GIS空间分析法,定性与定量结合分析研究区聚落分布形态演变及其驱动因素,结果表明,1934—2019年土默特平原以小聚落为主,大规模聚落数量和比例逐年增加,人口等级结构由“扁平”向“长高”金字塔形转变。聚落空间分布整体呈现集聚分布特征,大规模聚落集聚性不显著,其他规模的聚落分布模式由随机向集聚转变,研究区人口极化现象显著;聚落空间分布非均衡发展趋势明显,呈现由极核式向点轴式演变的迹象;聚落网络联系的空间近邻效应显著,人口规模较大的中心城区成为强联系节点。地形、河流、交通是研究区聚落分布形态演变的主要驱动因素,聚落低海拔、邻河流、邻干道、邻城镇的指向性强。该研究便于厘清土默特平原近百年聚落分布形态的演变脉络,为当地聚落的空间布局优化与调控提供一定参考价值。     

如何书写具有中国特色的文明史

21世纪以来,受西方文明史研究的影响,中国的文明史研究迅速热络起来。不仅有一批西方文明史著作被翻译出版,中国学者自身编写的文明史著作也纷纷出版。不过从总体来看,目前在文明史研究和写作中占据主导地位的还是西方的文明史书写范式.     

盈寸纤研 伦敦大英博物馆与华莱氏博物馆藏鼻烟壶鉴赏

15世纪末,航海家哥伦布把美洲印地安土著的烟草与吸闻鼻烟的习俗带回欧洲。而后十余年间,吸闻鼻烟迅速成为西班牙和法国宫廷的时尚,传统吸食烟斗的方式逐渐沦为下等阶层的象征。16世纪末,意大利传教士朝贡鼻烟,大获明万历皇帝赏识,从此舶来品—鼻烟在中国落地生根。17世纪60年代,当23岁的法王路易十四登基17年后终于亲政,开始引领＂中国风＂装饰,大规模采购中国瓷器、家具装饰凡尔赛宫时,英国王子查理二世结束九年的流亡生涯,回英即位。这位游历欧洲、精通艺术的皇帝把很多法国上流社会的习俗带回英国。     

Spatial–temporal distribution and geographic context of Neolithic cultural sites in the Hanjiang River Basin,Southern Shaanxi,China

Understanding how to live successfully within our environment is among the most pressing challenges facing contemporary society. This paper probes the problem based on comparative analysis and discusses the relationship between the spatial–temporal distribution of the Neolithic cultural sites and the geographic context in the Hanjiang River Basin in the south of Shaanxi Province, China. Archaeological studies have identified 175 Neolithic cultural sites in the study area, with a sequence of Laoguantai (¹⁴C age 8–7 ka BP), Yangshao (¹⁴C age 7–5 ka BP) and the late period of the Neolithic Age (¹⁴C age 5–4 ka BP). The total number of archaeological sites, the distribution area and the density all showed an early ascending and later descending trend, but the proportion of the number of archaeological sites in the study area to the corresponding value of the entire Shaanxi Province declined sharply. Spatially, these sites were concentrated on the terraces of the Hanjiang River and its main tributaries with an altitude of 400–800 m. Multiple data were integrated to clarify the critical effects of tectonic and geomorphologic conditions on the distribution of the Neolithic sites. Further comparisons revealed the correlation of Holocene climate change and environmental evolution with the Neolithic cultural succession in the study area that ameliorated conditions to generally promote the development of the primitive culture while degeneration coincided with the culture's transition or interruption. The discussion on the origin of the primitive culture and the temporal–spatial distribution corresponding to the regional culture differentiation sheds light on the complex and dynamic human–nature interaction system during the Neolithic Age, thus emphasising the wider field-based investigation and high-resolution reconstruction works of the palaeoclimate and palaeoenvironment in the future.