The physical,chemical,and microscopic properties of masonry mortars from Alhambra Palace (Spain) in reference to their earthquake resistance

Al-Andalus mortar is an ancient binding material (lime mortar) that was used for centuries in numerous historical buildings in Al-Andalus,Granada (Spain).The physico-chemical and microscopic properties of Al-Andalusmortars in Granada were studied as part of an investiga-tion into the mineral raw materials present in the territory of Spain.Scanning electron microscope and X-ray diffraction analyses of eight main types of mortars were performed to show the presence of calcite, gypsum, quartz, and muscovite minerals with organic fibers. Chemical analyses of the specimens showed that high SiO2+Al2O3+Fe2O3 contents yielded high values of hydraulicity and cementation indices. A significant result of this study was that mortars with high hydraulicity and cementation indices have high mechanical strengths.This characteristic may be the main reason for the earthquake resistance of the historical Alhambra Palace.     

Byzantine mortars of the Negev Desert

The choice of appropriate materials for restoration of historical buildings depends on scientific data from the analysis of materials used for the original construction. In this study the results of X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses of different Byzantine mortars from a church in the Negev Highlands, Israel, are considered. Moreover, the possibility for the production of lime in this area and its use as a mortar binder are discussed. It was concluded that the mortar for floor was prepared on the basis of local loess. The mortar for wall stonework contained lime as a binder.     

加固的历史风貌建筑墙体试验及结构抗震分析

针对天津现存的历史风貌建筑普遍存在砂浆强度低的情况,研究了原材料砖砌体及加固砖砌体试件的抗震性能。制作了2片原材料墙体试件、4片原材料墙体钢筋网水泥砂浆抹面加固试件,并对其进行了低周反复加载试验。应用等效体积单元(RVE)法对砖砌体进行模拟,对加固砖砌体则提出采用二次RVE法进行模拟,求得了其等效参数。用有限元模拟了加固墙体试件的低周反复荷载试验,并与试验进行了对比分析。最后对某一历史风貌建筑进行了加固前后的抗震性能有限元分析,验证了二次RVE法应用于加固砖砌体中的可行性。     

Cross validation of hygrothermal properties of historical Chinese blue bricks with isothermal sorption experiments

The historical,cultural,and social value of heritage buildings mandates special protection of these structures.Blue brick is one kind of the main construction materials of her-itage buildings,which is porous material and easily subject to deterioration due to environ-mental factors such as humidity.Therefore,determining the dynamic moisture content rule of materials under fluctuant ambient humidity is necessary for preventative conservation.This study measured the equilibrium moisture content of eight types of Chinese blue bricks under isothermal conditions with varying humidity levels.The results show that when ambient hu-midity increased from 10％to 90％,the moisture sorption of historical Chinese blue bricks tripled,which is 3 times greater than that of modern Chinese blue bricks and 10(at low humid-ity)to 20 times(at high humidity)greater than that of clay bricks in the international hand-book.The results contribute to the improvement of the international building material database and research related to hygrothermal performance of heritage buildings in East Asia.     

Cross validation of hygrothermal properties of historical Chinese blue bricks with isothermal sorption experiments

The historical, cultural, and social value of heritage buildings mandates special protection of these structures. Blue brick is one kind of the main construction materials of heritage buildings, which is porous material and easily subject to deterioration due to environmental factors such as humidity. Therefore, determining the dynamic moisture content rule of materials under fluctuant ambient humidity is necessary for preventative conservation. This study measured the equilibrium moisture content of eight types of Chinese blue bricks under isothermal conditions with varying humidity levels. The results show that when ambient humidity increased from 10% to 90%, the moisture sorption of historical Chinese blue bricks tripled, which is 3 times greater than that of modern Chinese blue bricks and 10 (at low humidity) to 20 times (at high humidity) greater than that of clay bricks in the international handbook. The results contribute to the improvement of the international building material database and research related to hygrothermal performance of heritage buildings in East Asia.     

灰缝厚度及水泥砂浆抹面对历史建筑砌体 结构性能的影响

在保证最小干预原则的前提下,对由于砂浆性能退化引起的历史建筑砌体结构安全性不足问题,提出了置换砂浆加固砌体结构的方法。以鼓浪屿历史建筑砌体结构为工程背景,模拟其结构力学性能,考虑不同灰缝厚度和单双面水泥砂浆抹面对历史建筑砌体结构性能的影响,共设计6个砌体试件,并进行了剪压复合试验。结果表明:在置换砂浆深度都是40 mm的情况下,灰缝厚度对砌体结构抗剪性能的影响十分显著,5 mm灰缝厚的试件比10 mm灰缝厚的试件承载力下降幅度为68.6%,而20 mm灰缝厚的试件比10 mm灰缝厚的试件承载力下降了8.7%; 在都未置换砂浆的情况下,单面水泥砂浆抹面的试件比未抹面的试件承载力提高了13.4%,双面水泥砂浆抹面的试件比未抹面的试件承载力提高了19.6%; 灰缝厚度和单双面水泥砂浆抹面对砌体结构的影响较为显著,在采用置换砂浆加固砌体结构时需要考虑这些影响; 试验结果可以为历史建筑砌体结构的加固提供一定的参考依据。     

Assessment of material use in relation to climate in historical buildings

Climate is among the most significant factors on the environmental performance, life span and/or durability of construction materials in buildings. Although some historical buildings have been abandoned and neglected for a very long period, their existence through centuries can be explained because of their durability to climatic conditions of the area where they are situated. In this study, construction techniques and characteristics of building materials used in some madrasas (historical education buildings) in Western Anatolia (Turkey) were examined in order to evaluate the conditions of the buildings by taking into account climatic conditions of the region. The studied Western Anatolian madrasas, which are in the moderate climatic conditions, were constructed out of rubble stone, brick and mortar in random bond with local workmanship by local builders who continued the older traditions and have survived for more than 300 years without maintenance and repair. On the other hand, most of the madrasa buildings in Central and Eastern Anatolia, which are in the steppe climatic conditions, were differently constructed with cut stone on their exterior surfaces to prevent the main structures of the walls composed of rubble stone and mortar from harsh climatic conditions of these regions. This study indicated that construction techniques and building materials appropriate to the climate might have been intentionally chosen for the survival of historical buildings over the centuries.     

Selection of plasters and renders for salt laden masonry substrates

The choice of a repair plaster or render by architects often appears to be the result of fortuitous circumstances, such as prior experience with a plaster or a recommendation by a producer. Seldom is the choice based on a sound assessment of the state of the building and the wall that is to be repaired. The service life of the repair plaster/render (and of the building to be conserved) is determined by many factors. In this paper, the most important factors affecting the risk of damage caused by salt are discussed, taking into account both the service life of the repair plaster/render and the conservation requirements of the existing building. The characteristics and performance of the various types of mortar for repair plaster or render are also reviewed. Next an attempt is made to evaluate the significance of the different factors affecting the choice of mortar. Then, taking into account the degree of risk of damage and performance data of the various types of repair mortar, possible mortar choices can be made for a repair plaster with an adequate service life. The final choice will depend on the specific conservation requirements for the existing building fabric.     

玻化微珠保温砂浆在建筑保温节能与抗震加固一体化中的应用

介绍了新型建筑材料玻化微珠保温砂浆,分析了其综合性能和应用范围。结合我国建筑节能和抗震加固的要求和现状．提出将玻化微珠保温砂浆用于保温节能和抗震加固一体化施工,阐述了将该材料用于一体化施工的技术可行性和经济合理性。     

机抹石膏砂浆在大型公建上的应用

在建筑施工中,加气混凝土砌块墙体特别是大面积墙体的粉刷容易产生空鼓开裂成为抹灰施工中的通病,也是后期投诉维修的难点。经过实践证明,采用专用石膏砂浆作为墙体粉刷材料,能解决此类通病。随着住宅科技的不断进步,在建筑抹灰工程中,机械喷涂抹灰施工也日趋增多。它能在很大程度上提高抹灰施工的效率,缩短施工期限,降低施工成本。加强对建筑施工特别是在大型建筑中利用灰浆泵进行喷涂抹灰施工很有必要。     

重庆湖广会馆的复兴

重庆湖广会馆是重庆城市中心区的重要古建筑群,具有很高的文物和历史文化价值。文章重点介绍了湖广会馆及其周边的社区复兴,湖广会馆古建筑的修复和再利用。修复设计中,将历史建筑保护与市场文化经济相结合,发挥其社会经济价值; 坚持文物保护的科学技术观,强调文物修复的“可识别性”原则,结合现代科技手段, 探索适合东方木结构体系的符合中国传统审美观念的有地域特色的历史建筑修复方法。     

对文物建筑修复原则运用尺度的几点看法

文物建筑保护修复原则和方法研究是历史文化遗产保护理论研究最重要的部分,对于在西方主流价值观基础上建立起来的文物建筑保护修复原则与方法的东方解读成为有中国特色文物建筑保护修复科学研究的重要组成部分。对保护修复中几个主要的原则,如修旧如旧、可识别性、现状保护以及复原重建等进行了阐述。     

Traditional organic additives improve lime mortars: New old materials for restoration and building natural stone fabrics

Portland cement has low chemical and physical affinity for traditional building materials. This hinders the restoration of historical buildings and modern rustic architecture where natural stone is used. Lime mortars used in construction since c.12,000 B.C. were recovered, and attempts were made to enhance their properties. Various additives were selected on the basis of their properties and historical use. These include polysaccharides (opuntia, also known as nopal used either as a powder or as mucilage), proteins (animal glue and casein) and fatty acids (olive oil). Six types of lime mortar were formulated and characterized. Compressive strength, water-resistance, carbonation speed, porosity, texture and mineral composition were measured. We propose new lime mortars with added value, i.e. increased mechanical properties and water-resistance, different carbonation speeds, and different textures. They are all compatible with traditional building materials, so they can be used in the restoration of architectural heritage and modern architecture where natural stone is used.     

Mechanical behaviour of lime based mortars after surface consolidation

Plasters have been used since ancient times in architectural applications to cover the masonry or to support paintings and decorations. Actually, plasters are subjected to several degradation phenomena which can lead to the loss of material cohesion mostly caused by the binder degradation. To recover the internal cohesion of the material is a very important topic in the conservation of historical architecture because alteration phenomena often produce the detachment of large areas of plasters (lacuna). Surface consolidation, directed to restore cohesion and stability, is based on the use of materials with aggregating properties. How to choose the best treatment with specific requirements is still a controversial issue. Actually, the lack of suitable evaluation protocols makes rather difficult the choice among the available consolidants, in spite of the research improvements which are patenting and presenting to the market new consolidation products. The testing protocols generally neglect the evaluation of mechanical properties (cohesion, adhesion and indentation) which are the base of the consolidating action of a material penetrating in the porous micro-structure of the substrate. In the case of plasters, the focus should be directed to the mechanical resistance of a composite thin material subjected to flexural strain. This study is aimed at determining the suitability of the four-point bending test, a flexural strength test, to evaluate the efficacy of consolidation treatments for plasters, used in the practice of conservation and restoration of ancient buildings.     

Heritage risk index: A multi-criteria decision-making tool to prioritize municipal historic preservation projects

The current pressure on the built historical heritage requires a global evaluation to develop strategies for its preservation. A combined vision of the state of conservation of architectural heritage is essential to highlight the vulnerabilities of the structure from which harmonized measures can be proposed for its mitigation.This study proposes a multi-criteria analysis methodology that considers a qualitative and quantitative approach to organize the global conservation state of heritage buildings hierarchically. A global index can be determined on the basis of the generation of an interoperable data matrix by defining a set of indicators to assess different components of a building. This index describes the risk with respect to the stability, safety, and habitability of the building.This methodology aims to achieve the state of the building in an integral way by obtaining a simple and objective index that enables efficient comparison among different buildings. The application of this methodology to a historic area allows creating a hierarchical map of risk to stablish priorities for intervention and enable a sustainable and critical management and planning over the actions of maintenance, conservation, and restoration. In this way, a holistic vision of the complex reality of built heritage and the urban landscape is obtained to identify critical areas of priority intervention.     

民国某仿木构钢筋混凝土结构的加固设计

民国仿木构钢筋混凝土建筑是具有典型中国特色的建筑遗产,大多承载着重要历史文化信息,对其加固修缮应在符合文物保护原则的前提下合理进行结构性能和耐久性的提升。结合浙江某民国仿木构钢筋混凝土结构加固修缮实例,较全面地讨论了仿木构钢筋混凝土结构类型的民国建筑在加固设计中应考虑的若干关键问题,包括检测鉴定、计算分析、混凝土构件加固及墙体加固等,介绍一些有效的解决办法,如钢丝网聚合物砂浆抹面法加固混凝土柱和梁、钢筋网聚合物砂浆抹面法加固混凝土板等,能满足后续使用年限30年的要求,可供同类建筑物加固修缮参考。     

为什么要保护古建筑

本文全面论述了保护古建筑的重要意义,对提高和增强人们的文物保护意识,促进我国的文物保护工作有很重要的作用。古建筑是古代物质文化遗存中极其重要的一个组成部分,是文物保护中重要的一项。原因在于建筑物的功能不仅是作为生产、生活的物质资料,而且它还有作为上层建筑意识形态领域方面的政治表现、艺术欣赏、历史见证等方面的作用。要保护古建筑的理由有（1）古建筑是启发爱国热情和民族自信心的实物;（2）古代建筑是研究各门历史科学的实物例证;（3）古建筑是新建筑设计和新艺术创作的重要借鉴;（4）古建筑是人民文化、游息的良好场所,是开展旅游的重要物质基础。要把古代历史上遗留下来的实物作为研究历史科学的实物例证,把古代劳动人民积累下来的经验为今天的建设作为参考,总之一句话,就是：“古为今用”。     

21世纪的古建筑保护与修复

２１世纪的古建筑保护与修复不仅关系到人类神经物质文明的发展,而且与人类文化遗产的延续息息相关。     

An Italian contribution to architectural restoration

The essay provides an up-to-date review of the realities of Italian restoration. Restoration work feeds off the doubt that stems directly from historical and balance, and a conceptual rigour and practical approach at the same time. Restoration is carried out always and only on the original, with all the attendant risks of error and damage, and thus with all the prudence that demands.One of the most recent definitions of restoration is put forward: “By restoration, therefore, is meant any intervention that has the aim of conserving and transmitting to the future works of historical, artistic and environmental interest, facilitating the reading of them while not erasing the traces of the passage of time this is based on a respect for ancient material land the authentic documentation that such works constitute and, moreover, is to be seen as a critical act of interpretation that is not verbal but expressed concretely in the work carried out. Or, more precisely, it is a critical hypothesis and a proposition that is always modifiable, without it ever altering irreversibly the original”.The true nature of restoration is a complete fusion of historical and technical-scientific expertise. It is therefore artificial to distinguish between a ‘project of consolidation’ and a truly described restoration project. This is a distinction based on the assumption (to be demonstrated) that in an ancient building static problems and those related to the materials can be isolated and treated separately from an overall understanding of the architectural ensemble. So the paper stresses research methodology, the project and specific skills. As part of the principle of unity of methods in restoration, interdisciplinarity is viewed as the principal tool for bringing together consistently and fully the different skills necessary for the study and conservation of monuments.In summary, there are three fundamental components: (1) the history of architecture and theory of restoration; (2) the techniques of survey, analysis, diagnosis and intervention on the materials and the structure; and (3) legislative and regulatory aspects.The author emphasises the link between restoration and access to the monumental heritage. The definition of restoration as ‘an act of culture’ (fundamentally critical-historical and technical-scientific) leads to the reflection that culture is, by definition, exchange, communication and opening up to people without distinction. So restoration, because of its cultural nature, has need of recommendations, trends and orientations rather than regulations.Restoration looks to the future, not to the past. It has educational and commemorative functions for future generations, for young people; it ultimately is concerned not with satisfaction with research per se but the preparation of all citizens and their quality of life, viewed in the widest possible spiritual and material sense.In conclusion, some perspectives for the new millennium are offered. We have to ask ourselves whether society today is still able to guarantee a role for memory, for history and for the value of traditions, or for beauty itself. At first sight, it seems that interest in conservation and restoration has been reinforced in recent times. At the same time, we are aware of dominant pressures wanting to renovate and redesign our environment, giving priority above all to economic factors and revenue. To recall an earlier declaration by Renato Bonelli: contemporary society is not interested in historical and artistic things in themselves, whether they are ancient or modern. It is practical and consumerist, but it is also a society of complexities, and that however opens up some vents.     

Conservation and modern architecture. Fortune and misfortune of the School of Mathematics at Rome University (G. Ponti, 1932–1935)

The framework of the Italian restoration doctrine is based on the reception and transmission of the memory of the past. However, interventions in modern architecture represent a radical drift in the sense that they mostly consist of reconstructions, refurbishments, and renovations. Such work disregards the sense of value acknowledgment that is implicit in architectural conservation and neglects the importance of material conservation. The uneven fortune of the School of Mathematics at Rome's University Campus illustrates this situation. This predicament is similar to that of many other modern buildings that have been declared “monuments” by mouth but are actually bent to listless and insensible use, mistreated, and hardly maintained. The recent work carried out at the School of Mathematics proves that interventions on modern buildings are mostly insensitive to their true significance and are often carried out in extreme urgency for mere practical reasons, if not for political opportunities. Modern buildings can be true architectural monuments that express great esthetic potentials and retain notable historical weight in the history of architecture; therefore, they should be regarded as highly representative of our recent past and maintained as such.