Understanding and controlling the ingress of driven rain through exposed, solid wall masonry structures

Long term performance of historic buildings can be affected by many environmental factors, some of which become more apparent as the competence of the fabric deteriorates. Many tall historic buildings suffer from water ingress when exposed to driving rain conditions, particularly church towers in the south west of England. It is important to recognise that leakage can occur not only through flaws in the roof of a building but also through significant thicknesses of solid masonry. Identification of the most appropriate intervention requires an understanding of the way in which water might enter the structure and the assessment of potential repair options. While the full work schedule used an integrated assessment involving laboratory, field and archival work to assess the repairs which might be undertaken on these solid wall structures, this paper focuses on the laboratory work done to inform the writing of a Technical Advice Note on the effects of wind driven rain and moisture movement in historic structures (English Heritage, 2012). The laboratory work showed that grouting and rendering was effective at reducing water penetration without retarding drying rates, but that use of internal plastering also had a very beneficial effect

Procedural Surface Weathering of Cultural Stone Through Physically Based Mesh Deformations

Weathering in computer graphics is crucial to creating believable objects. Common methods to add wear to an object include the application of 2D texture maps or direct model deformations through sculpting. These methods require an artist’s time and expertise, often at a cost to quality or iteration time for the asset. This creates a need for a method that is quick to iterate upon and easy to manipulate. This thesis outlines a new procedural method that combines principles of 2D texture maps and 3D sculpting to achieve large-scale mesh deformations in stone surfaces. The method involves the use of procedural 3D noise to define a stone’s composition combined with particle systems to simulate rainfall on an object, deforming it over time. A custom user interface with preset stone options is implemented to reduce the level of expertise needed to use the system

P-04 Cavan Burren 2015 Project

The Cavan Burren is a plantation forest within the Marble Arch Caves UNESCO Global Geopark overlay along the Republic of Ireland and Northern Ireland border. The exposure of Cavan Burren’s relict landscape resulted from a 2012 partial clear fell. Our multidisciplinary team of researchers in architecture, technology, ecology, fine arts, and archaeology investigated domestic architecture reflected in three stone configurations: circular/semicircular sites, rectangular sites, and tomb structures. We also investigated human action on pedestal boulders (PBs), which had been modified by sculpting, splitting, and cutting away. Our first goal was to show human action on structures by using three-dimensional (3D) analyses to investigate relationships among cast-off pieces and resulting modified boulders. Our second goal was to compare our findings with those from Ancient Near East regions, particularly Cisjordan and Transjordan, to explore possible sociocultural parallels. Photographs of artifacts were taken from different angles, organized sequentially, and stitched together via specialized software to create 3D models with photorealistic textures. We also used fine-art (drawing/painting) techniques to render objects in situ, to gain deeper detail than obtained by modern photography alone. We digitally manipulated 3D images to test-fit cast-off remains with split-pedestal boulders and to understand how monuments were made, worked, and assembled. Digital analyses suggest that certain matched sets of boulder parts, previously split and exposed to the same weathering effects, were worked by human action. Comparative analyses suggest that small, circular rings of moderate-sized stones, designated on mapping as Hut Sites, were likely places of cultic activity near tomb structures

Connectivity Compression for Irregular Quadrilateral Meshes

Applications that require Internet access to remote 3D datasets are often limited by the storage costs of 3D models. Several compression methods are available to address these limits for objects represented by triangle meshes. Many CAD and VRML models, however, are represented as quadrilateral meshes or mixed triangle/quadrilateral meshes, and these models may also require compression. We present an algorithm for encoding the connectivity of such quadrilateral meshes, and we demonstrate that by preserving and exploiting the original quad structure, our approach achieves encodings 30 - 80% smaller than an approach based on randomly splitting quads into triangles. We present both a code with a proven worst-case cost of 3 bits per vertex (or 2.75 bits per vertex for meshes without valence-two vertices) and entropy-coding results for typical meshes ranging from 0.3 to 0.9 bits per vertex, depending on the regularity of the mesh. Our method may be implemented by a rule for a particular splitting of quads into triangles and by using the compression and decompression algorithms introduced in [Rossignac99] and [Rossignac&Szymczak99]. We also present extensions to the algorithm to compress meshes with holes and handles and meshes containing triangles and other polygons as well as quads

Gesture politics and the art of ambiguity: the Iron Age statue from Hirschlanden

NoThe discovery of the extraordinary Hirschlanden figure was reported in this journal in 1964. Since then the statue has featured in numerous discussions of Iron Age art and society, to the extent that it has become one of the iconic images of the European Iron Age. It has become almost taken for granted that the Hirschlanden figure is an `intensely masculine¿ warrior statue representing the heroised dead. However, certain aspects of the figure suggest a rather deeper, more ambiguous symbolism. The authors use their up-to-date critique to raise questions about the eclectic character of Iron Age spirituality

The utility of single-point seismic data

A massive amount of information is available to the explorationist in the form of correlation-point seismic data recorded over the past 40 years, yet the archaic nature of the data inhibits its use. To the geophysicist trained in the modem technology of digital recording, computer processing, modeling, and seismic stratigraphy, these analog records are readily dismissed as being hopelessly outdated and incapable of containing any reliable information. To the geologist, they are just so many wiggles. An analysis of exploration targets and economics, however, reveals that these single-point records are the most cost-effective means of acquiring seismic information about the subsurface and when used within their limitations, correlation-point records can improve drilling success rates. Because of this, thousands of records are still being shot and recorded every year. In fact, this method of seismic exploration is the dominant method used today in Kansas. It is important then for the geologist and geophysicist to be able to recognize the utility and limitations of the tool and its role in prospect evaluation. This paper is intended to give the explorationist an exposure to the field-recording techniques, the data-reduction methods, and the mapping of shot-hole seismic records

The utility of single-point seismic data

A massive amount of information is available to the explorationist in the form of correlation-point seismic data recorded over the past 40 years, yet the archaic nature of the data inhibits its use. To the geophysicist trained in the modem technology of digital recording, computer processing, modeling, and seismic stratigraphy, these analog records are readily dismissed as being hopelessly outdated and incapable of containing any reliable information. To the geologist, they are just so many wiggles. An analysis of exploration targets and economics, however, reveals that these single-point records are the most cost-effective means of acquiring seismic information about the subsurface and when used within their limitations, correlation-point records can improve drilling success rates. Because of this, thousands of records are still being shot and recorded every year. In fact, this method of seismic exploration is the dominant method used today in Kansas. It is important then for the geologist and geophysicist to be able to recognize the utility and limitations of the tool and its role in prospect evaluation. This paper is intended to give the explorationist an exposure to the field-recording techniques, the data-reduction methods, and the mapping of shot-hole seismic records

Geophysical Study at Old Stone Fort State Archaeological Park, Manchester, Tennessee

The Old Stone Fort State Archaeological Park covers over 800 acres within Manchester, Tennessee, and is owned and managed by the Tennessee Division of State Parks. The central archaeological site within the park boundary is The Old Stone Fort mounds that enclose about 50 acres on a plateau above the convergence of the Big Duck and the Little Duck Rivers. The hilltop enclosure dates to the Middle Woodland Period, and radiocarbon dates obtained at the site range from the first to the fifth century A. D. Because of its size and apparent complexity, previous investigations of the site have been quite limited in areal exposure. Many questions remain as to the overall structure of the site, including the relationship of built and natural features, the presence of any structures or other anthropogenic features, and the occurrence of presence of any domestic remains. This research project utilizes detailed digital topographic survey, geographical information system (GIS) analysis, geophysical survey, limited re-excavation of previously investigated portions of the site, and manual coring to locate and characterize archaeological deposits within the enclosure and mounds. Magnetometer, resistance, electromagnetic susceptibility, conductivity, and ground penetrating radar techniques were used during the investigations. Geophysical data, using these instruments, were collected over the same area in many cases. All together 20,000 m2 were examined during the project. Results indicate potential archaeological features and deposits within the plateau interior. Analysis suggests the presence of several geophysical anomalies potentially associated with prehistoric use of the site, especially within the Eastern Gateway complex. One such anomaly, or complex of anomalies, represents a possible structure. Historic archaeological deposits are also indicated by the geophysical data. Excavations at the site were limited to minimize impact. In a re-excavated trench, a lens of black shale within the stone mound construction may indicate a building stage not previously observed at Old Stone Fort. A second excavation confirmed a ditch feature detected in the geophysical survey. Archaeological deposits located during the survey are interpreted as evidence of sustained use of the ceremonial site during the Middle Woodland Period by local corporate groups to maintain and intensify membership for individuals who were settled in nucleated villages throughout most of the year

Interactive translucent volume rendering and procedural modeling

Journal ArticleDirect volume rendering is a commonly used technique in visualization applications. Many of these applications require sophisticated shading models to capture subtle lighting effects and characteristics of volume metric data and materials. Many common objects and natural phenomena exhibit visual quality that cannot be captured using simple lighting models or cannot be solved at interactive rates using more sophisticated methods. We present a simple yet effective interactive shading model which captures volumetric light attenuation effects to produce volumetric shadows and the subtle appearance of translucency. We also present a technique for volume displacement or perturbation that allows realistic interactive modeling of high frequency detail for real and synthetic volumetric data

Problemas de durabilidad de los materiales de construcción arqueológicos en ambientes acuosos y subaéreos, con aplicaciones a la restauración y conservación en Egipto y Sudán.

The main objective of the study was to identify and assess the conservation problems of the building materials of each case study and compare the aggressive impacts of each environment on the sustainability of the construction materials. Carefully, the construction materials (limestone, sandy limestone, sandstone, lime mortars, gypsum, hydraulic lime mortar/roman mortar) were selected from different archaeological sites with different environmental conditions in Egypt and Sudan (desert: Sahure?s pyramid and pyramids of Meroe; urban/agricultural: Nero/Ramses II Temple; coastal: Anfushi?s Necropolis; and fluvial: Abaton/Osiris Temple). To achieve this goal, field observations, analytical (X-ray diffraction, X-ray fluorescence, Raman spectroscopy, UV-Vis spectrometry), microscopic (binocular microscope, polarizing microscope and scanning electron microscope), mapping (AutoCAD, ArcMap 10.8, SeaDAS, QGIS), and physical and mechanical testing investigations were carried out. Furthermore, open-access satellite lenses were used for the detection and assessment of the archaeological sites and their risks, and, the deterioration patterns of each case study were recorded through decay mappings. Finally, to preserve the lime mortar surfaces, a newly synthesized nanomaterial of SiO2-TiO2 NPs/TEOS was applied and tested. The results showed the severity of each factor on the construction materials. In this sense, Sahure?s pyramid was affected mainly by climatic and environmental factors, earthquakes and the inner composition of the building materials. Nero/Ramses II Temple showed its susceptivity mainly from the salt attack which came from the contaminated sources of water around the temple. Water intrusion, earthquakes, storms, and heavy rains factors attacked Anfushi?s Necropolis severely. Abaton/Osiris Temple was decayed because of Nile water fluctuations impact and the inner weakness of the temple sandstones. In Sudan, the pyramids of Meroe were damaged because of the sand dunes and wind forces, in addition to the flooding risks. Finally, and concerning to the heritage conservation, the research exhibited the efficacy of the multifunctional 3% and 5% SiO2-TiO2 NPs/TEOS in the consolidation and improvement of the physical and mechanical ancient lime mortars