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1.
This paper deals with the scientific assessment of the physical properties of sandstone used in the conservation of Sydney's historic heritage sandstone buildings. The local Hawkesbury Sandstone has been widely used for all manner of constructions since the early days of the first settlement. In the nineteenth century, dimension sandstone quarries existed all over the Sydney region, and the demand for the stone was great. During this time, a true ‘freestone’ known as ‘yellow block’ sandstone, in which bedding planes were absent, was quarried extensively. This sandstone is also known as a ‘self-colouring’ sandstone, where the rock, although grey when quarried, turns a yellow–brown after a few months exposure to the atmosphere. It can be easily carved and was eminently suitable for the ornate Victorian architecture of the time. There are very few quarries within the Sydney region today capable of producing ‘yellow block’ sandstone. Whenever possible, sandstone from suitable building excavations, particularly on the Pyrmont Peninsula, is used for this work. Conservation work is extremely expensive and the building elements that most need replacement, the overhanging and decorative elements, are usually those that cost the most. It is essential that the most durable replacement stone be selected. Thus, a strict regime of scientific testing is used for any major conservation project, in order to determine the physical properties of possible replacement stone. This is the province of the geologist and involves visual observation in the quarry or excavation, which is a simple, cost-effective means of weeding out poor quality stones, followed by laboratory engineering tests to establish the physical parameters of a sandstone and finally, petrographic analysis. The results of such tests, combined with careful sampling, ensure the best possible quality of replacement material.  相似文献   

2.
The sawing rate is one of the most significant and effective parameters in extracting building stones via diamond wire sawing. This parameter designates the capability of diamond wire sawing for sawing different stones; in addition, the parameter gives rise to economical considerations for quarry designers. In this study, the existent relations between stone geotechnical parameters and the sawing rate of stones via diamond wire sawing were analyzed using regression and correlation coefficient as well as the collected data from Marmarit stone quarries. Moreover, we estimated the sawing rate of Marmarit using the dimensional stone rock mass rating (DSRMR); upon comparison of the data obtained from DSRMR our pre‐collected data on quarries, we did not gain satisfactory results from DSRMR, hence we used artificial neural network (ANN). The results showed that the percentage of Silica, the coefficient of water absorption, the uniaxial compressive strength (UCS), and abrasive hardness are the proper parameters for creating the ANN. Discontinuities have the least effects possible on diamond wire sawing. Having given the training possibility of the ANN, and its ability to evaluate relations among input parameters, the ANN, which was being trained with Marmarit's traits, was an accurate network for estimating diamond wire sawing in Marmarit quarries, although it could not generalize this network for other stones such as Chini and Crystal. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

3.
Dimensional stones with a black color occupy a prominent place on the international market. Uruguayan dolerite dikes of andesitic and andesitic–basaltic composition are mined for commercial blocks of black dimensional stones. A total of 16 dikes of both compositions were studied and samples collected for geochemical and petrographical analysis. Color measurements were performed on different black dimensional stones in order to compare them with the Uruguayan dolerites. Samples of the two commercial varieties (Absolute Black and Moderate Black) were obtained for petrophysical analysis (e.g. density, porosity, uniaxial compressive strength, tensile strength, etc.). Detailed structural analyses were performed in several quarries. Geochemistry and petrography determines the intensity of the black color. The Uruguayan dolerite Absolute Black is the darkest black dimensional stone analyzed in this study. The petrophysical properties of Uruguayan dolerites make them one of the highest quality black dimensional stones. Structural analyses show that five joint sets have been recognized: two sub-vertical joints, one horizontal and two diagonal. These joint sets are one of the most important factors that control the deposits, since they control the block size distribution and the amount of waste material.  相似文献   

4.
Euganean trachyte is a subvolcanic porphyritic rock extracted in northern Italy with an age-old tradition of use as dimension stone, historically linked, in particular, to the fervent building activity brought by the Roman Empire and, later on, the Republic of Venice Serenissima. The results of a comprehensive petrophysical and mechanical characterization of Euganean trachyte from the most representative quarries are discussed here, involving the following properties: density, porosity, water absorption, capillary water uptake, hygroscopic water adsorption, hydric/hygric dilatation, water vapor diffusion, thermal expansion, and resistance to salt attack and abrasion. The different trachyte varieties, although belonging to the same quarry basin, exhibit a relatively wide array of technical performances, which are strongly dependent on pore volume, size, size distribution, shape, and degree of interconnection, controlling modes and rates of water transport and retention. Therefore, indications are provided for evaluating durability performance of the stone, with stress on water-driven weathering. Complementary information is finally given on the possible criteria followed in the antiquity for properly selecting the trachyte quarries to be exploited, and by a comparison with the properties of the most important trachytes extracted in Europe.  相似文献   

5.
This paper documents the results of nondestructive X‐ray fluorescence (XRF) geochemical analyses and comparisons of silicified rhyolites from the Black Canyon and Sedillo Hill prehistoric quarries near Socorro, New Mexico, and subsequent comparisons of the quarry rhyolites with 11 temporally diagnostic projectile points. At the current level of analysis, findings indicate that (1) the two quarries are chemically distinct and (2) the lithic materials of two projectile points match the silicified rhyolite from the Black Canyon quarry, suggesting quarry use during the Early Archaic period (4800–3200 B.C.) and the Late Archaic period (1800–800 B.C.). A close match between the Black Canyon rhyolite and one other point provides tentative support for use of the quarry during the Clovis Paleoindian period (9500–9000 B.C.). Additional geochemical analyses of the two quarries and other regional sources should be undertaken to verify these results and further expand our understanding of prehistoric mobility in the Southwest. © 2004 Wiley Periodicals, Inc.  相似文献   

6.
《Chemical Geology》1999,153(1-4):37-51
The aim of the present work is to determine the origin and background of 72 samples of four varieties of granite s.l. from quarries and different parts of the Cathedral Group Buildings of Avila (Spain) subject to different microenvironmental conditions. To do so, the results of the chemical analyses of major and trace elements of all samples were analysed statistically using the inertia method based on an HJ-biplot. Clusters of samples related to their origin, quarry or building were obtained. The statistical method employed is a useful tool for determining the origin of the stone located on different parts of the historical monument. This is of great interest when the stone needs to be replaced for maintenance and restoration purposes.  相似文献   

7.
Cutting performance of diamond wire saw is a key factor influencing mine planning, production scheduling, and equipment selection for dimension stone quarries. It is normally measured in terms of cutting rate. Rock samples collected from various granite and marble quarries in India were tested in laboratory to determine their physico-mechanical properties. Cutting rate of diamond wire saw was measured in the field studies during the actual cutting process in quarries. Using these laboratory determined properties and the cutting rate, a multiple linear regression model has been developed to predict the cutting rate of diamond wire saw. Physico-mechanical properties of rocks determined in laboratory are used as independent variables and cutting rate as predictor variable in the regression model. The study indicates that the cutting rate increases with a decrease in most of the hardness and strength parameters of rock. The final model is tested for its goodness of fit indicating a significant linear relation between cutting rate and physico-mechanical properties, namely tensile strength, slake durability index, and Cerchar hardness index with regression coefficient of 94%. The resulting model can be used suitably for different types of hard to medium hard and soft dimension stones. The generalized model for estimating the cutting rate becomes a handy tool for mining engineers to work out operating efficiency, expenses, planning etc. of the dimension stone block cutting.  相似文献   

8.
Paleocene limestone and dolomitized limestone of Álava, Spain, were used as building materials from the Neolithic age until the Neoclassical, predominantly in the production of headstones, sculpture, and stonework during the Roman era (1st to 4th centuries) and Romanic and Gothic periods (10th to 15th centuries). The quarrying methods employed are related to topographic relief. Five types of ancient quarry have been identified: escarpment, dip‐slope (ascending and descending), edge, and trench. The oldest quarries (1st to 4th centuries) are the trench‐cut stone pits of “Raso de Cezama.” Later, from the Romanic period (10th to 15th centuries), descending dip‐slope, escarpment, and edge‐based quarries were worked, such as those at Achuri, Ajarte, and Santa Elena. Finally, an ascending dip‐slope quarry was developed at Marquínez during the Neoclassical period (18th century). © 2009 Wiley Periodicals, Inc.  相似文献   

9.
Metacarbonates of the Moldanubian Zone (Bohemian Massif, Czech Republic) were studied to obtain qualitative and quantitative mineralogical-petrographic as well as stable isotopic data for the purpose of stone provenance studies, potentially applicable in material research studies of cultural heritage artefacts. Twenty-six samples from twelve different historical quarries, as well as two samples from historical artefacts, were analysed by both mineralogical-petrographic and geochemical methods including: polarizing microscopy, cathodoluminescence, scanning electron microscopy with microanalysis, petrographic image analysis, powder X-ray diffraction, and isotope ratio mass spectrometry. The petrographic characteristics allowed for the discrimination of groups of (1) calcitic marbles, (2) dolomitic marbles, and (3) carbonate–silicate rocks. These groups exhibit characteristic features such as (1) the presence/abundance of major rock-forming minerals, (2) grain geometric characteristics (specifically, mean carbonate grain size and index of grain size homogeneity), and (3) the presence of specific accessory phases. The content of non-carbonate minerals, some rock fabric parameters, as well as the carbon and oxygen isotope data exhibited significant variability, even within a single quarry in the case of some impure marbles and carbonate–silicate rocks. Although the carbon and oxygen isotopic ranges displayed overlaps among the quarries studied, the isotopic signatures throughout the Moldanubian Zone allowed for discrimination of a group of white calcitic marbles with high carbon and oxygen depletion, as well as white dolomite–calcitic marble with higher carbon isotope values when compared with other marble resources of the Bohemian Massif. A combination of the isotopic signature with detailed mineralogical-petrographic characteristics seems to provide sufficient information for discrimination of the Moldanubian marbles from one another. The provenance of the Vrchotovy Janovice artefact is very probably from the Rabí quarry, among the Moldanubian marbles. The provenance of the artefact from the Prague Klementinum was not definitively assigned; however, the Nehodiv quarry was considered its probable source locality.  相似文献   

10.
A multi-disciplinary study was undertaken of the Lower Old Red Sandstone building stones of Bromyard, Bromyard Downs and Bringsty Common, Herefordshire, UK, to trace their original quarry sources. 196 stone structures were recorded in detail and 3 broad lithological groups recognised. Combining old maps, archival sources, Light Detection and Ranging (LiDAR) data and testimony of local residents, the historic quarries in the area have been mapped. Field studies of the geology of quarries and outcrops have established the area of origin of two distinctive coarse grained lithologies. Intraformational conglomerates have been demonstrated, with some confidence, to be derived from Bromyard itself. Coarse, pebbly, quartzose sandstones have been traced to Bringsty Common and shown to be used only in the church in Bromyard before the 20th century. The origins of fine grained sandstone are found to be more complex. Through a combination of fieldwork and archival research, Clater Park Quarry is indicated as the origin of high quality green sandstones in Bromyard. 15 samples of sandstone from the Bromyard Downs, have been petrographically analysed by point counting to determine their clastic and mineralogical proportions. Early results of this analysis are presented which show modal variation in lithics, feldspars and cements that may serve to link quarries to buildings. Finally, it is suggested that at least some of the diversity of stone present in Bromyard is the result of slight variation in depositional processes in the immediately underlying bedrock.  相似文献   

11.
Stone substitution is a conventional operation during heritage buildings’ restoration, but becomes problematic for architects and restorers when the quarry is mined out. The compatibility of the substitution stones with the original ones has been for long mainly based on the aesthetical aspect, this resulting too often in a patchwork of original and substitution stones with different patina after several years because of differences of properties. In this study, the objective is to show how substitution stones can be selected by combining aesthetic criteria and stones properties that are relevant for analyzing their compatibility. A couple of French limestones with their potential substitution stones were selected for the study. Our results showed that potential substitution stones selected on their aesthetic criteria require to be rejected because of their differences of physical properties. On the other hand, our results showed also the possibility to select substitution stones with satisfactory aesthetic aspect and properties that enable to expect a satisfactory compatibility with the original stone.  相似文献   

12.
上海佘山风景区是国家旅游度假区,也是上海唯一的基岩集中出露区。其间有七家采石厂以下挖 式进行石材开采,遗留采石坑占地近14×10~4m~2。采石坑存在重大安全隐患,并对环境景观造成严 重影响。本文结合度假区总体建设规划,提出采石坑环境治理对策,并论述其可行性。采用注水 是综合效应良好的可行方案。  相似文献   

13.
South Australia has the greatest utilisation of heritage or building stone in Australia because of its lack of timber resources. Consequently, natural stone was intensively used from the beginning of European colonisation. Building stones in South Australia, notable for their variety given the State’s diverse geology, can be challenging to designate as to their international importance. However, dimension stone in South Australia can also be designated as having national, regional, local or prospective importance. Commonly, stone in South Australia is restricted in use to a specific town, or even a single construction, and has only local significance except where use involves special stone characteristics, unusual stone masonry or use in a building with significant heritage. For instance, the town of Second Valley has a localised use of marble, likely the earliest use (1849) of this rock type in the State. Another example, ‘Adelaide Black Granite’, quarried since 1958, should probably be recognised internationally as a ‘Global Heritage Stone Resource’, as it has had intensive monumental use around Australia, utilisation as cladding in modern buildings, as well as paving and walling in Australia’s National Parliament in Canberra. It has also been exported, notably used for the Australian Embassy in Japan and for a major War Memorial at Le Hamel, France. South Australian slate quarries also provide significant heritage stone. For example, the Willunga Slate quarry south of Adelaide has been sourced for roofing slate and walling since 1840 and is arguably the longest continuous mining operation in Australia; this resource has obvious national significance given a period of quarrying extending to the present, coupled with national distribution of its products. Probably the most widespread stone sourced in South Australia is the surface limestone or calcrete, quarried in the Adelaide area until the 1850s and used for general construction. The stone continues to be used in rural areas. While arguably only of local significance, it could be considered to have national importance because of its extensive use in churches, public building, hotels, houses and simple walling across a vast area of South Australia. Additional research is needed to clarify the heritage status of many building stones used in South Australia.  相似文献   

14.
Optimized extraction of dimension stone blocks   总被引：1，自引：1，他引：0  
The profitable production of dimension stone mainly depends on the extractable block size. The regularity and volume of the blocks are of critical importance, and are controlled by the three-dimensional pattern of the discontinuity system. Therefore, optimization of block size has to be the aim when quarrying for natural stone. This is mainly connected to the quantification of joints and fractures, i.e., their spacing and orientation. The problem of finding unfractured blocks within arbitrarily oriented and distributed planes can be solved effectively by a numerical algorithm. The main effects of joint orientations on block sizes and shapes will be presented in this article. Quantification of unfractured blocks with the aim of optimization is illustrated by detailed studies on several quarries. The algorithm used in this study can be applied as a powerful tool in the planning of a quarry and the future exploitation of dimension stone. Application of the described approach is demonstrated on practical examples of quarrying natural stones, namely, sandstone, granite, rhyolite, etc. Block quarrying can be optimized by using the new 3D-BlockExpert approach. The quantification of unfractured rock masses is also shown to contribute to a more ecological protection and the sustainable use of natural resources.  相似文献   

15.
To reduce the weathering rate of natural building stones, a wide variety of water repellents and consolidants are commercially available. Although a lot of research is performed on these products, it remains difficult to determine which product is appropriate to use for a certain type of building stone. Each type of building stone has its own petrographic characteristics (mineralogy, texture, …), leading to typical physical and technical properties which influence its rate of decay. The localisation of the products inside a stone type is not only depending on the properties of the products themselves, but also linked to the texture and structure of the stone. The impregnation depth of the products strongly influences their efficiency and is therefore a key issue in the determination if a product is functional for a certain type of stone. X-ray micro-CT has recently been introduced as a non-destructive material evaluation technique for engineering and geology purposes. The fact that micro-CT can provide information about the internal structure and properties of natural building stones, is a major advantage in the study of their conservation. Firmly linked with more classical research techniques, this non-destructive technique offers an extra dimension to the cultural heritage research.In this paper, non-destructive X-ray computed micro-tomography (micro-CT) turns out to be a powerful tool as it can visualise the presence of water repellents and consolidants inside the stone and can help to detect the influence that these treatments exert on porosity and pore-size distribution. For the visualization of the product its atomic number and density and the amount of product inside the natural building stone is crucial. Besides the contrast in attenuation, the resolution of the micro-CT also needs to be taken into account to obtain a good contrast between stone and product. By doping with 3-bromopropyltrimethoxysilane, more contrast occurs between the stone material and the conservation product. When the amount of product inside the samples is very low and the product is homogeneously spread inside the sample, the doped product is difficult to distinguish from the stone material due to the resolution of the micro-CT. When the amount of doped product inside the stone material reaches a certain threshold value, the dope will appear in the 2D cross-sections derived from micro-CT, creating a good visualization of the products inside the stone samples.  相似文献   

16.
 I˙stanbul, the capital of the east Roman, Byzantine and Ottoman Empires embraces two continents, one arm reaching out to Asia, the other to Europe. It is therefore, a rich city in terms of monuments and historical cites. Shell limestones of Upper Miocene age are used as building stone in the majority of the monuments in I˙stanbul because of their attractiveness, availability and workability. The durability characteristics of the limestones are examined, and those factors that are responsible for atmospheric weathering are discussed, in a humid and marine environment with important problems of urban pollution, specifically due to traffic. In the present study weathering of the building stones were first examined in situ by macroscopic observations. The weathering that developed as a result of environmental effects since this limestone was first used in historical monuments has been affected 0.1–1.5 cm deep from the surface. The weathered facing stone of Şehzade Mehmed Mosque in I˙stanbul is undergoing a program of progressive replacement. During this study, samples were taken from this monument where the shell limestone was used. The stone surface was principally examined by means of Scanning Electron Microscopy (SEM). Petrographical and mineralogical analyses were made by using optical microscopy and X-ray diffraction method. The physico-chemical properties of these rocks control their weathering behaviour and reactivity. Major and trace element analyses and the effect of deterioration on the physical properties of the limestones (unit weight, porosity and water absorption) have also been investigated. Studies on the samples implies that weathering on the stone surface caused important variations on the physical characteristics of the rock. Received: 11 February 1998 · Accepted: 18 August 1998  相似文献   

17.
Building stones have long been one of the most widely used construction materials in the world. Building stones used in historical monuments are deteriorated partly or completely depending on the environmental and atmospheric effects. In recent years, non-destructive test methods have been used to assess deterioration of building stones used in historical monuments. Gödene stone is one of the building stones being widely used in the historical buildings in the Konya region, Central Anatolia. The most deterioration effects are observed in the Ferit Pa?a Cistern among the historical structures built with Gödene stone in the region. The aim of this study is to assess the deteriorating effects in the street façade of the Ferit Pa?a Cistern via non-destructive testing methods (Schmidt hardness rebound value, P-wave velocity, humidity measurement and thermal imaging) and create maps of deteriorated features. Turkey’s historic places are integrated to Turkish culture, efforts are made to conserve heritage through rehabilitation. Therefore, this study will help developers and federal managers during the project planning stage by providing technical data.  相似文献   

18.
The St Bavo's Cathedral tower in Ghent, Belgium, is currently under restoration. This tower was built during the fifteenth and sixteenth centuries over a period of 73 years, using Eocene white stone. Restorations over the last two centuries introduced different Jurassic limestones from the Paris Basin. Documentation of these interventions, however, is very poor for the period before the twentieth century, and documentation on the original construction is non‐existing. Nevertheless, the use of the different stones in their historical context forms a typical example of the historical mindset on the use of white stone, representative for Ghent and by extension northwestern Belgium.  相似文献   

19.
The stone traditionally used to build cities contributes to their personality and attests to the geological substrate on which they stand. While stone decay in the built heritage can be attributed to a number of causes, anthropic activity has a particularly significant impact. The geomonumental routes project is one of the initiatives proposed in recent years for urban routes that convey geological fundamentals by observing the rocks present in heritage structures. Its innovative approach addresses traditional stone properties, original quarrying sites and mechanisms of decay. Madrid’s Royal Palace is a fine example of the use of traditional building stone in the centre of the Iberian Peninsula. In the geomonumental route proposed, the building doubles as an in situ laboratory that affords an overview of the main petrological properties of the two traditional stones most commonly used in the city’s built heritage, the forms of decay they are subject and the factors underlying such alterations. This route constitutes a tool for showing the main petrological features and decay forms in traditional building stones found in urban heritage façades, with a special focus on anthropic impact, primarily air pollution and the use of conservation treatments that time has proven to be unsuitable.  相似文献   

20.
Natural building stones are commonly used for a broad variety of purposes in the construction of many different types of buildings. Knowledge of the permeability of natural building stones, which are widely used in interiors, exteriors, flooring, veneering, landscaping, and walkway laying, is important for correctly determining their lifetime as well as their areas of use. The current study proposes a new test method to determine the air permeability of natural building stones, based on a previously developed method used to assess the permeability values of concrete samples. In this context, the air permeability index values of 96 natural building stone samples, belonging to 16 different types of natural stones classified into five groups, were determined using a new air permeability testing apparatus. The obtained permeability values were compared with the water absorption, open porosity, and apparent density properties of the natural building stones. Strong correlations were identified between the air permeability values of natural building stones and the open porosity and water absorption values. In contrast to other types of tests, the designed apparatus allowed information to be obtained concerning the porosity of natural building stones within a time period as short as 6 h. Based on the obtained results, the air permeability values of the natural building stones were classified into three groups as permeable, semi-permeable, and non-permeable. The study results indicated that the air permeability index can be effectively used to measure the air permeability of natural building stones within a short a period of time and by using a simple test apparatus.  相似文献   

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