水在广西花山岩画风化病害中的作用及其防治对策

花山岩画位于广西壮族自治区宁明县,其保存环境特征是高温潮湿多雨,花山岩画受环境因素作用,岩画颜料及岩石风化明显,风化类型复杂多样,有化学风化、物理风化和生物风化,同时存在、相互影响。它们均与水分有着直接的或间接的关系,因此水的防治是治理岩画风化病害的前提。本工作在水分来源及岩画保存地区地形地貌现场调查的基础上,通过水质分析系统研究了水在岩画风化病害过程中的作用。提出了花山岩画防水治水原则,并结合地质环境和特殊的地形地貌,将整个治水区域划分为山体山顶治水、溶蚀洼地治水、岩画立壁治水三个区域。根据其不同的渗水机制,分别采用盖、堵、排、导相结合的综合防水治水方法。由于岩画病害机理极其复杂,花山岩画防水、治水的难度很大,必须采取区别对待,综合治理的方法。     

西藏博物馆藏品虫害调研与防治

西藏博物馆馆藏文物丰富、特色浓郁,但由于历史条件等原因,文物虫害一直存在并产生危害。为制定虫害治理方案,本工作从害虫检测入手,对西藏博物馆的害虫进行检测分析,阐述了文物保护工作中虫害预防治理的重要性,并就虫害的危害特性、种群特性以及预防治理的必要性和紧迫性进行论述。根据西藏博物馆的现状,分别针对库存文物和展览文物的环境特点和虫害情况制定虫害治理方案,并选择虫害较严重的库、馆进行了实验性治理,对库存文物及环境在所有文物原地不动的前提下进行了整体熏蒸防治,对展馆环境及展存文物进行了整体的消杀防治,均取得了预期的满意效果。通过实验治理的操作过程和效果体验,认识到化学防治的安全、快捷、高效、简便和实用,同时结合多年的文保工作经验,提出了对馆藏文物保护的一些建议。     

Preliminary Assessment on Seismic Vulnerability of Masonry Churches in Central Chile

ABSTRACT

The 2010 Maule Chile earthquake (Mw 8.8) caused extensive structural damage to the built heritage. In particular, the poor seismic performance of a set of unreinforced masonry (URM) churches highlighted the need to implement protective and safety strategies in order to preserve these buildings which exhibit unique constructive and typological features, as a result of a combination of Chilean and European construction cultures.

The peculiarity of this heritage and the high seismic hazard of Chilean territory have motivated the present study which aims to apply systematic procedures to assess the seismic vulnerability of these buildings. This article is of archival nature and presents a complete database generated from the geometrical, constructive, and structural characteristics of a representative stock of 106 churches located in central Chile, with the goal of proposing fragility curves to be used in seismic risk assessment. Considering variables related with geometrical, architectonic, and stylistic features, as well as damage levels for the 2010 Maule earthquake, this church sample is classified into three homogenous groups: colonial, neo-classic, and neo-gothic. Moreover, a preliminary qualitative assessment of the seismic capacity of these structures is provided using a survey and analysis of geometric indices for each of the three selected groups.     

Experimental Out-Of-Plane Behavior of Brick Masonry Infilled Frames

ABSTRACT

The vulnerability of masonry infills within reinforced concrete (rc) frames under out-of-plane loading induced by earthquakes has been observed in several past earthquakes through severe damage and often total collapse. Although the infill panels are assumed as non-structural elements, their damage or collapse is not desirable, given the possible consequences in terms of human life losses and repair or reconstruction costs.

Therefore, it is important to gather better insight on the out-of-plane behavior of existing infills so that strengthening guidelines can be derived. In this scope, the main objective of this study is to analyze the out-of-plane experimental behavior of masonry infilled frames that are characteristic of Portuguese buildings and can be seen in other south European countries. In the experimental study carried out, different parameters affecting the out-of-plane response of infilled frames were considered, namely, workmanship, existence of openings and prior in-plane damage. The experimental program was designed to test six half-scale specimens. The out-of-plane loading was applied uniformly to the brick infills by means of an airbag to simulate the effect of earthquakes.     

A Multidisciplinary Study on the Seismic Vulnerability of St. Agostino Church in Amatrice following the 2016 Seismic Sequence

ABSTRACT

The big earthquake of August 24, 2016 and subsequent major shocks severely damaged many historic villages in Central Italy and dramatically showed the intrinsic vulnerability of the diffused architectural heritage. The St. Agostino church is one of the collapsed historical buildings, being inside the epicentre village of Amatrice. During the long seismic earthquake swarm, progressively the church was damaged and monitored. This multidisciplinary study of the damage of the church includes correlations of all the data derived from three steps geomatics surveys (3D aerial and terrestrial models): the archival drawings and images documenting previous events distressing the building, the previous strengthening intervention, and finally the seismic site response analysis (from Amatrice’s accelerometric station). Through a back analysis carried out by a finite elements model, it was possible to understand the seismic vulnerability of this historical building, in relation to the previous interventions and damage events. The proposed methodology, based on the interdisciplinary data analysis, provides useful information for the next strengthening projects of damaged historical monument.     

馆藏砖石质文物有害盐中多种无机及有机酸阴离子的定量分析

博物馆环境空气中无机或有机酸性污染气体会腐蚀馆藏砖石质文物并使其表面出现有害盐。常见的有害盐种类复杂，可能同时含有无机和有机酸阴离子。为进一步认识文物盐害和分析盐害产生的原因，本研究建立了一种基于离子色谱的有害盐中无机和有机酸阴离子定量分析方法。该方法可同时测定馆藏砖石质文物上有害盐中氟离子、氯离子、溴离子、硝酸根、亚硝酸根、磷酸根、硫酸根、甲酸根、乙酸根、丙酸根、丁酸根、戊酸根等十二种阴离子。采用2～30 mmol/L KOH淋洗液梯度洗脱，能够在35 min的检测时间下实现该十二种阴离子的快速分离与准确检测。所有阴离子的标准曲线的相关系数均高于0.995,检出限为0.001～0.022μg/mL,定量限为0.004～0.073μg/mL;加标回收率为81.8%～107.0%。该方法采用超纯水作为溶剂，样品处理简单，易于操作；具有成本低廉、检测时间短和准确性高的特点；可定量计算有害盐中多种无机及有机酸阴离子的质量分数。将该方法应用于中国国家博物馆馆藏“汉并天下”瓦当和仿制玉炉表面有害盐中的无机及有机酸阴离子的分析，可为分析盐害发生的原因，阻止、延缓及预测盐害的发生提供依据。     

Study on Damage Assessment of Earthen Sites of the Ming Great Wall in Qinghai Province Based on Fuzzy-AHP and AHP-TOPSIS

ABSTRACT

As a world-renowned heritage site, the Ming Great Wall in Qinghai Province, is an example of an earthen site that is seriously threatened by a series of deterioration. Its damage assessment is the precondition for further protection planning and implementation, but related research was found to be scant. To fill this gap, we explore to study its damage assessment by applying Fuzzy-AHP and AHP-TOPSIS to determine the damage assessment levels for 18 earthen sites selected from Qinghai Province, combined with their occurrence environment, engineering properties of rammed earth, deterioration characteristics, and building technologies. After obtaining and comparing results, the AHP-TOPSIS is indicated to be much closer to the real damage conditions. Therefore, this method is proved to be more suitable for the damage assessment of earthen sites in Qinghai Province. This study also holds the potential application of the AHP-TOPSIS in the damage assessment for other earthen sites in Northwest China.     

The palaeopathology of a finger dislocation

The Ruffner collection, a Late Period (AD 500–1800), northern California skeletal sample, was analyzed for osteopathology. A probable fifth-finger dislocation of the right first and second phalanx was observed in a female aged 25–35 years at death. Traumatic adduction forced the second and third phalanges to slip laterally, upward and back about 10 mm, upon the dorsal surface of the first phalanx. Apparently, the medial collateral ligament of the interphalangeal joint was torn, making reduction impossible. As a result of the luxation, the flexor digitorum profundus slipped laterally and was fixed along the lateral surface of the distal end of the first phalanx. Over time, fusion of the joint restricted the flexion movement and left an abnormally aligned finger.     

Numerical Modeling of a Church Nave Wall Subjected to Differential Settlements: Soil-Structure Interaction,Time-Dependence and Sensitivity Analysis

ABSTRACT

Historic masonry structures are particularly sensitive to differential soil settlements. These settlements may be caused by deformable soil, shallow or inadequate foundation, structural additions in the building and changes in the underground water table due to the large-scale land use change in urban areas.

This paper deals with the numerical modeling of a church nave wall subjected to differential settlement caused by a combination of the above factors. The building in question, the church of Saint Jacob in Leuven, has suffered extensive damage caused by centuries-long settlement. A numerical simulation campaign is carried out in order to reproduce and interpret the cracking damage observed in the building.

The numerical analyses are based on material and soil property determination, the monitoring of settlement in the church over an extended period of time and soil-structure interaction. A sensitivity study is carried out, focused on the effect of material parameters on the response in terms of settlement magnitude and crack width and extent. Soil consolidation over time is considered through an analytical approach. The numerical results are compared with the in-situ observed damage and with an analytical damage prediction model.     

受控冷冻灭虫法的风险控制

受控冷冻灭虫的关键在受控,受控指标包括冷冻温度、降温速度与冷冻时间,受控的目的是要达到彻底灭虫。冷冻温度与降温速度直接影响到被冷冻物品的形体安全,保障物品安全为前提的受控冷冻灭虫需要管控风险。基于文献分析、相关问题的调研与理论研究发现,温度不够低、降温速度不够快以及灭虫时间过短都会造成灭虫不彻底的风险。极端低温与快速降温带来物品的损伤与被冷冻物品的材料性质相关,将在极端低温与热冲击力下必然会损坏的材料排除在冷冻灭虫的许可范围之外,科学地选择冷冻温度与加强冷冻灭虫过程管控,可使受控冷冻灭虫化险为夷,即以保证藏品安全为前提的彻底灭虫。