Building in Historical Areas: Identity Values and Energy Performance of Innovative Massive Stone Envelopes with Reference to Traditional Building Solutions

The intrinsic nature of local rocks shaped the features of built heritage in historical centers. The resulting building culture is part of the cultural heritage itself, and must be considered when building in such areas, while it is essential to solve the issues related to traditional constructions’ weaknesses. Nonetheless, the potentialities of massive stone envelopes, particularly the importance of thermal inertia, have contributed to redefining the language of contemporary architectural culture. Nowadays, although the trend of employing thin stone cladding panels is prevalent, thick stone envelopes are gaining a renewed importance. Previous literature demonstrated that mixed building technologies or massive stone envelopes coupled with load-bearing framed structures are able to meet comfort and safety requirements and to guarantee the integration of new constructions in the consolidated urban landscape, avoiding historicist approaches. This research, through the analysis of case studies, aims to describe innovative building solutions developed by contemporary architectural culture, comparing them with traditional stone masonry walls. Moreover, thermal energy performance of such building solutions is assessed through dynamic yearly simulations. Results show that these solutions are technically and architecturally suitable to build in historical centers, because they can express urban cultural identity and guarantee good energy performance and users’ comfort

Interdisciplinary on-site evaluation of stone bunds to control soil erosion on cropland in Northern Ethiopia

Since two decades, stone bunds have been installed in large areas of the Tigray Highlands, Northern Ethiopia, to control soil erosion by water. Field studies were conducted to quantify the effectiveness, efficiency, side effects and acceptance of stone bands. Based on measurements on 202 field parcels, average sediment accumulation rate behind 3-21 year old stone bunds is 58 t ha(-1) year(-1). The Universal Soil Loss Equation's P-factor for stone bunds was estimated at 0.32. Sediment accumulation rates increase with slope gradient and bund spacing, but decrease with bund age. Truncation of the soil profile at the lower side of the bund does not lead to an important soil fertility decrease, mainly because the dominant soil types in the study area (Regosols, Vertisols and Vertic Cambisols) do not have pronounced vertical fertility gradients. Excessive removal of small rock fragments from the soil surface during stone bund building may lead to a three-fold increase in sheet and rill erosion rates. Negative effects of runoff concentration or crop burial by sediment deposition due to bunds were only found over 60 m along 4 km of studied bunds. AS the rodent problem is widespread and generally not specific to stone bands, it calls for distinct interventions. On plots with stone bands of different ages (between 3 and 21 years old), there is an average increase in grain yield of 53% in the lower part of the plot, as compared to the central and upper parts. Taking into account the space occupied by the bunds, stone bunds led in 2002 to a mean crop yield increase from 0.58 to 0.65 t ha(-1). The cost of stone bund building averages 13.6 ha year(-1), which is nearly the same as the value of the induced crop yield increase in 2002 (13.2 ha(-1) year(-1)). Besides positive off-site effects such as runoff and flood regulation, the enhanced moisture storage in deep soil horizons on both sides of the bunds indicates that the stone bund areas can be made more productive through tree planting. We conclude that from the technical, ecological and economical point of view, the extensive use of stone bunds, involving people's participation, is a positive operation. Overall, 75% of the farmers are in favour of stone bund building on their land, which is a clear indication that the local community perceives this conservation measure as being beneficial. (c) 2006 Elsevier B.V All rights reserved.status: publishe

Contributions of X-ray CT to the characterization of natural building stones and their disintegration

This paper highlights the use of the high resolution scanner at the Centre for X-ray Tomography in Ghent, Belgium (UGCT), for the 3D quantitative evaluation of the disintegration of some French natural building stones. Rocks deteriorate when they are exposed to extreme weathering factors such as a combination of water and freeze-thaw cycles or high pressure. The results of those processes can be very diverse: from element migration to crust formation to the origination of micro-cracks. Thanks to its non-destructive character, high resolution computed tomography (CT) turned out to be an excellent monitoring tool as it contributes to the characterization of the internal structure of the natural building stone. X-ray CT also provides a better insight into the micro-structural durability properties of the building stone

Rapa Nui (Easter Island)’s Stone Worlds

This article explores the spatial, architectural and conceptual relationships between landscape places, stone quarrying, and stone moving and building during Rapa Nui’s statue-building period. These are central themes of the ‘Rapa Nui Landscapes of Construction Project’ and are discussed using aspects of the findings of our recent fieldwork. The different scales of expression, from the detail of the domestic sphere to the monumental working of quarries, are considered. It is suggested that the impressiveness of Rapa Nui’s stone architecture is its conceptual coherence at the small scale as much as at the large scale

The urban heat island effect on frost damage of natural building stones

Climate plays a major role in the weathering of building stones. This study specifically investigates the influence of the urban heat island (UHI)in Ghent, Belgium,on freeze-thaw (F-T) weathering ofnatural building stonesand their hydrophobicequivalent. Climatic analysis of data of two places in and around Ghent indicates higher temperatures and lower wind speeds in the city center. This leads to a reduced number of F-T cycles and a lower wind-driven load.Hygrothermal modelling of a natural building stone, Savonnières limestone,is performed for the urban and rural climate of Ghent on the untreatedlimestone and on the treatedlimestoneto assess the freeze-thaw risk inside thesematerials.Urban climate has a mitigating effect on the potential frost risk in natural building stones as a result of the urban heat island. Additionally, the application of a water repellent product reduces the potential frost risk even more, since the water density in the stone is reduced

Assessing the potential for reopening a building stone quarry : Newbigging Sandstone Quarry, Fife

Newbigging Sandstone Quarry in Fife is one of a number of former quarries in the Burntisland- Aberdour district which exploited the pale-coloured Grange Sandstone from Lower Carboniferous rocks. The quarry supplied building stone from the late 19th century, working intermittently from 1914 until closure in 1937, and again when reopened in the 1970s to the 1990s. The stone was primarily used locally and to supply the nearby markets in the Scottish Central Belt. Historical evidence indicates that prior to sandstone extraction, the area was dominated by largescale quarrying and mining of limestone, and substantial sandstone quarrying is likely to have begun after the arrival of the main railway line in 1890. It is probable that removal of the sandstone was directly associated with limestone exploitation, and that the quarried sandstone was effectively a by-product of limestone production. Sandstone extraction was probably viable due to the existing limestone quarry infrastructure (workforce, equipment, transportation) and the high demand for building stone in Central Scotland in the late 19th century. The geology within Newbigging Sandstone Quarry is dominated by thick-bedded uniform sandstone with a wide joint spacing, well-suited for obtaining large blocks. However, a mudstone (shale) band is likely to be present within a few metres of the principal (north) face of the quarry, around which the sandstone bed thickness and quality is likely to decrease. The mudstone bed forms a plane sloping at a shallow angle to the north, so that expansion of the quarry in this direction is likely to encounter a considerable volume of poor quality stone. Additionally, an east-west trending fault is present approximately 100 metres north of the quarry face, which is also likely to be associated with poor quality (fractured) stone

Montgomery: Jeff Davis\u27 Seal of Solomon

Set into the marble steps of Alabama\u27s Capitol building is a brass star. Gleaming against the white stone, the star stands at the top of the stairs on the Capitol\u27s west face. The star reads, Placed by Sophie Bibb Chapter Daughters of the Confederacy on the spot where Jefferson Davis stood when inaugurated President of C.S.A. Feb. 16. 1861. [excerpt

Building Stones of the U.S.

By examining the NIST Stone wall via the Internet, students will determine the weathering rate of various rocks in the mid-Atlantic region. They will then pick a rock to use in building their "dream house" and justify their choice. Students should have a background in types of rocks. Educational levels: High school

The Global Warming Potential of Building Materials: An Application of Life Cycle Analysis in Nepal

open6siThis paper analyzes the global-warming potential of materials used to construct the walls of 3 building types—traditional, semimodern, and modern—in Sagarmatha National Park and Buffer Zone in Nepal, using the life-cycle assessment approach. Traditional buildings use local materials, mainly wood and stone, while semimodern and modern buildings use different amounts of commercial materials, such as cement and glass wool. A comparison of the greenhouse gas emissions associated with the 3 building types, using as the functional unit 1 m2 of wall, found that traditional buildings release about one-fourth of the greenhouse gas emissions released by semimodern buildings and less than one-fifth of the emissions of modern buildings. However, the use of thermal insulation in the modern building walls helps to reduce the energy consumption for space heating and consequently to reduce the global warming potential. In 25 years, the total global warming potential of a traditional building will be 20% higher than that of a modern building. If local materials, such as wood, are used in building construction, the emissions from production and transportation could be dramatically reduced.openBhochhibhoya, Silu; Zanetti, Michela; Pierobon, Francesca; Gatto, Paola; Maskey, R. K.; Cavalli, RaffaeleBhochhibhoya, Silu; Zanetti, Michela; Pierobon, Francesca; Gatto, Paola; Maskey, R. K.; Cavalli, Raffael