The ‘Triple R’ Approach on the Restoration of Archaeological Dry Stone City Walls: Procedures and Application to a UNESCO World Heritage Site in Oman

The ‘Triple R’ approach on the restoration of dry stone walls, using recognizable, reversible and respectful constructive techniques is here illustrated. A set of restoration procedures are explained and applied to a UNESCO World Heritage site in Al-Baleed (Salalah, Sultanate of Oman) in the ‘Land of Frankincense’. The procedures were adapted in an innovative way to take into account the climate features of the Indian Ocean area (specifically, the effects of the monsoon season). All the restoration procedures aimed at conserving the site’s original architectural features by using only suitable stones and materials found on-site. Specific procedures have been adopted to consolidate walls, gates, foundations and sloping surfaces. Simple on-site mechanical tests and evaluation methods have been developed for a quick assessment of the safety level of the restored walls to ease future archaeological excavations. The application is related to a waterfront side of the ancient city built around the ninth century and added to over the next five centuries. These restoration procedures allowed for further archaeological excavations with new findings is here described.     

Influence of Short Segments in the Trabeation With Opposing Inclined Edges on the Seismic Vulnerability of the Marble Blocks Colonnade in the Archaeological Site of Pompeii

This study presents the vulnerability analysis of a masterpiece of the architectural heritage of the ancient city of Pompeii in Italy. First, a historical analysis of the structure is proposed; then finite element analyses are discussed to evaluate the seismic vulnerability of the colonnade today, including the effect of water leakage and pollutants in between the marble blocks of the structure. Pompeii, in fact, is a partially buried Roman town-city; after suffering many earthquakes in the past it was destroyed during a long catastrophic eruption of the Vesuvius volcano in 79 ad and remained covered until its accidental rediscovery in 1749. After excavations, the ruins of the ancient town present many partially collapsed buildings, not only due to other earthquakes during the past three centuries, but also due to rapid degradation of the archaeological material. Temples and public places mainly present slender columns and typical shapes of discrete marble overlaying blocks. In the case of the colonnade of the Forum, residing in the main square of the town, an “innovative solution” was adopted for the trabeation. To avoid long span beams over the columns, short segments were built up providing opposing inclined patterned edges. Numerical analyses show the seismic vulnerability of a colonnade, in order to understand how a UNESCO World cultural heritage site can be preserved. The beam segmentation was an “innovative solution” for that period aiming to simplify the constructability of those structures. This solution did not substantially alter the colonnade current seismic vulnerability. Nevertheless any contemporary alteration between blocks could potentially increase the colonnade’s seismic vulnerability, potentially putting at risk cultural heritage and human life.     

Seismic vulnerability assessment methodology for slender masonry structures

ABSTRACT

Slender masonry structures such as towers, minarets, chimneys, and Pagoda temples can be characterized by their distinguished architectural characteristics, age of construction, and original function, but their comparable geometric and structural ratios yield to the definition of an autonomous structural type. These structures constitute a part of the architectural and cultural heritage. Their protection against earthquakes is of great importance. This concern arises from the strong damage or complete loss suffered by these structures during past earthquakes. Seismic vulnerability assessment is an issue of most importance at present time and is a concept widely used in works related to the protection of buildings. However, there is few research works carried out on developing the seismic vulnerability assessment tools for such structures.

This article presents a new method for assessing the seismic vulnerability of slender masonry structures based on vulnerability index evaluation method. The calculated vulnerability index can then be used to estimate structural damage after a specified intensity of a seismic event. Here, 12 parameters are defined to evaluate the vulnerability index for slender masonry structures. Implementation of this methodology is carried out in different types of slender masonry structures to develop vulnerability curves for these structure types.     

The afterlife of earthen-core buildings: A taphonomic study of threatened and effaced architecture in Central Belize

Buried architecture poses an interpretive challenge to field archaeologists the world over. The depositional sequence of the site must be reconstructed through excavation and stratigraphic analysis, and the various phases of construction and use that occurred in the past must be inferred. Effaced earthen-core architecture (e.g., architecture that was once faced with a masonry outer layer that is no longer present) constitutes a heightened challenge in this regard, as events and layers are not always clearly distinguishable, an interpretive difficulty that can be compounded when such architecture is threatened and decay accelerated by modern-day land use activities such as bulldozing and plowing. The case study presented here focuses on an ancient Maya E-Group architectural configuration—a triangular arrangement of structures that served to commemorate astronomical events, among other functions—that is being degraded through repetitive plowing. The significance of this site in regard to Maya archaeology is undeniable, as it was used and reused over a period of at least eight centuries. The site warranted a salvage-based approach designed to gather maximal quantities and types of data when only a minimal amount of time, labor, and funding was available. The procedure presented here was developed for a specific example of endangered, earthen-core Maya architecture in Belize; however, it is applicable to any archaeological project that faces similar obstacles in examining and documenting architecture before it is either eroded or intentionally destroyed.     

Stephenson’s Roundhouse in Context: Excavations at the Stratford Locomotive and Carriage Works,London Borough of Newham

This article explores the findings of a developer-funded archaeological investigation undertaken by Pre-Construct Archaeology at the Eastern Counties Railway’s Stratford Works, Angel Lane, London Borough of Newham. The investigations revealed truncated walls and in situ floor surfaces of terraced housing, as well as an early engine house and associated structures, constructed in accord with a design of Robert Stephenson’s. With a construction date of 1840, it represents an early example of a railway roundhouse, the first in London. In Britain, developer-funded archaeological projects have resulted in the preservation by record of several comparable sites prior to their adaptive reuse or demolition in recent years. As well as contextualising the results of the excavation more generally, this article therefore aims to improve the understanding of the evolution and life-history of the Stratford roundhouse and its environs, as well as British railway roundhouses more generally, via a comparative approach, the ultimate aim being to demonstrate that developments within the excavated sections of the Stratford site fit within a broader architectural, archaeological, and historical narrative.     

Evaluation of Structural Intervention in the Quartel das Esquadras,Almeida (Portugal)

ABSTRACT

The “Quartel das Esquadras” is an 18th century infantry barrack located within the limits of the bulwarked fortress of Almeida, in Portugal. An ongoing adaptive reuse project of the building aims to recover its full capacity and also its importance, by implementing a variety of new uses. The architectural intervention results in the need of the structure to withstand new and diverse imposed loads. As the current configuration of the structure will be altered, the main objective of this article is to evaluate the suitability of some of the proposed structural interventions. The current condition has been characterized following a multidisciplinary approach comprising historical research, visual inspection, non-destructive testing, and structural analysis to identify the possible sources of major structural problems. A portion of the building particularly affected by the alterations has been selected to carry out structural analysis. A comparative safety assessment of the selected area in both current and altered condition has been done through finite element modelling and nonlinear static analysis, resulting in an identification of the weaker points against the new implemented loads and alterations. Finally, proposals for the implementation of the studied intervention, as well as recommendations for future research and analyses, have been given.     

Seismic vulnerability assessment and fragility analysis of stone masonry monastic temples in Sikkim Himalayas

Buddhist monasteries in Sikkim Himalayas constitute important religious and architectural heritage. These random rubble (RR) stone masonry structures located in high seismically active regions of the Himalayas have suffered varied degrees of damages in the past earthquakes. The study presents seismic vulnerability assessment of four archetypal monastic temples using finite element (FE) analyses. Linear and nonlinear analyses of these structures were conducted in Abaqus FE environment. These analyses identified the damage prone areas of the structures and provided load-deformation behavior under lateral loads. Fragility analyses indicate a high probability of collapse for the specified design level earthquake of the region. The study shows that performance of the structure can be enhanced by improving the strength and stiffness of the stone masonry walls.     

A Late Hellenistic–Early Roman Fortress at Khirbat Mudayna as-Saliya,Central Jordan

ABSTRACT

Mudayna as-Saliya is a fortress site at the summit of an isolated promontory near the eastern end of Wadi Mujib, central Jordan. Archaeological surveys of the site have exposed potential evidence of Iron Age and classical period use with its occupational zenith in the late Hellenistic-early Roman period. The ruin on the surface is remarkably similar in architectural and hydrological design to the fortress of Machaerus. This paper, based on available survey data, suggests that the Hasmoneans were responsible for the construction of the fortress at Mudayna as-Saliya, which was reused by the Nabateans during the early Roman period. Finding a potential Hasmonean desert fortress on the desert fringe of eastern Transjordan was unexpected, and it might have significant ramifications for the study of Hasmonean, Herodian, and Nabatean kingdoms in central Jordan.     

AUTOMATIC MINIMIZATION OF THE RIGIDITY ECCENTRICITY OF 3D REINFORCED CONCRETE BUILDINGS

The objective of this paper is to obtain the optimum design of 3D reinforced concrete buildings in terms of their performance under earthquake loading. This goal is achieved by considering the minimisation of the eccentricity between the mass centre and the rigidity centre of each storey layout as the optimisation objective in order to produce torsionally balanced structures. This problem is considered as a combined topology and sizing optimisation problem. The location and the size of the columns and the shear walls of the structure of each storey layout constitute the design variables. Apart from the constraints imposed by the seismic and reinforced concrete structure design codes, architectural restrictions are also taken into account. The test examples showed that a reduction in the structural cost of the building is achieved by minimising the eccentricity between the mass centre and the rigidity centre of each storey layout. Evolutionary optimisation algorithms and in particular a specially tailored algorithm based on Evolution Strategies is implemented for the solution of this type of structural optimisation problems.     

Radiocarbon Dating of Architectural Mortar: A Case Study in the Maya Region,Quintana Roo,Mexico

Abstract

The use of radiocarbon dating to analyze mortar and charcoal inclusions within mortar or plaster is a useful way to date the construction of architecture, particularly when options for other chronometric methods are limited. In the Yalahau region of northern Quintana Roo, Mexico, members of the Yalahau Regional Human Ecology Project have faced challenges in dating buildings made of large blocks of stone in the Megalithic architectural style. The Megalithic style poses serious problems for any analysis, as excavating into structures with stones weighing several tons can be dangerous, expensive, and time consuming. Additionally, there are no associated sculptures, texts with dates, or other traditionally accessible chronological markers. These factors have resulted in a reliance on a ceramic chronology despite the uncertainty of the dating of many ceramic types in this region, as well as the questionable contextual associations between recovered ceramics and architectural construction phases. Megalithic-style structures at the ancient Maya site of El Naranjal have residual mortar with charcoal inclusions left behind during the mortar-making processes that can be extracted and dated with AMS ¹⁴C methods. Several samples of mortar and charcoal were obtained from structures 1 and 10 from exposed exterior walls and an interior vault. The resulting dates confirm the date for the construction based on ceramics excavated from the same site.     

Rehabilitation Techniques for Walls during the 18th Century in Cartagena de Indias (Colombia)

ABSTRACT

Although it may be thought that the rehabilitation of historical structures is a concern of modern engineering, studies on intervention processes from the past allow us to understand that this is a work carried out frequently and sometimes as a solution to low budgets for the construction of new buildings, or the need to offer quick practical solutions. The objective of this article is to show the way in which during the second half of the 18th century several important architectural and structural rehabilitation works were carried out in the walls of Cartagena de Indias, in view of the damage caused by the enemy attacks to the city as well as continuous impact by nature. By making use of primary sources (plans and original reports), the way in which two of the interventions were executed can be reconstructed: one on the Muralla Real, and another on the San José bastion, gathering information that helps explain their current state of conservation.     

Archaeological geophysics of a Bronze Age agricultural landscape: the AROURA Project,central mainland Greece

Between 2010 and 2012, the AROURA project conducted magnetometric prospection in the ancient polder around the Late Bronze Age (ca. 1300–1190 b.c.) fortress of Glas, mainland Greece. As had been hypothesized, the anomalies detected were consistent with a system of agricultural fields. This system appears to have been irrigated and drained through previously identified hydraulic mechanisms in and around the polder. Comparison of soil profiles of anomalies with those of background areas, including their magnetic susceptibilities, corroborated magnetometric data. Anomalies were traced from sampled to unsampled areas through corresponding reclassified satellite bandwidths. Constituent sediments of features discovered were dated to the Late Bronze Age through AMS radiocarbon and OSL analyses. The results validated the use of extensive geophysics to detect and investigate ancient agricultural landscapes.     

明清西北筑城碑记的形成、特征及历史地理学价值

据不完全统计,明清西北筑城碑记大约存有269篇,其中原碑尚存于世者32方,是研究明清西北城池史宝贵的一手资料。甘、宁、青三省现存明代碑记最有特色,有大量卫所营堡的筑城碑保留。州县碑记大多有若干时段连续的拓城记,连缀起来就是城池形态扩展的整体叙事。明清西北筑城碑记所反映的城镇类型也多种多样,州县城镇最多,卫所营堡占有一定比例,其他如驿城、巡检司城、厅城、寨城、关城都有一部分存留,非常难得。这些碑记作为第一手资料,详述了筑城过程、工程耗时、销银数量、捐资人户,对于考证原委、制度复原、社会阶层以及城镇职能与形态扩张都有极重要的史料价值。     

Rubble Stone Masonry Walls Strengthened by Three-Dimensional Steel Ties and Textile-Reinforced Mortar Render,Under Compression and Shear Loads

This article addresses the results of a structural strengthening solution for rubble stone masonry walls. The strengthening includes inserting three-dimensional steel ties across the thickness of the walls and a 30-mm layer of air-lime and cement mortar render reinforced with glass fiber mesh (textile-reinforced mortar), on both sides of the wall. The strengthening solution was found to be efficient for rehabilitating ancient rubble stone masonry walls due to the “three-dimensional” confinement, provided by the steel wires, by offsetting the low cohesive capacity of the mortar used in the walls and thus improving the mechanical resistance and delaying the collapse mechanisms. This study is part of an experimental research program carried out in Universidade Nova de Lisboa, to evaluate structural strengthening solutions for ancient rubble stone masonry buildings. To this end, three specimens of rubble stone masonry walls without strengthening (unreinforced masonry) and other three, with the mentioned strengthening solution, were subjected to compression and shear load tests. Building materials were also tested in order to characterize physical, chemical and mechanical properties.     

Seismic Performance Assessment of Slender T-Shaped Reinforced Concrete Walls

T-shaped slender reinforced concrete (RC) structural walls are commonly used in medium-rise and high-rise buildings as part of lateral force resisting system. Compared to its popularity, experimental results on seismic performance of these walls are relatively sparse, especially for data regarding these walls in the non-principal bending directions. This article aims at providing additional experimental evidence on seismic performance of T-shaped RC structural walls. Experimental results of six T-shaped RC walls were presented. These walls resemble the structural walls found in existing buildings in Singapore and possess slightly inferior details compared to the requirements of modern design codes. The test variables were the loading direction and the axial load ratio. The experimental results were discussed in terms of the failure mechanisms, cracking patterns, hysteretic responses, curvature distributions, displacement components, and strain profiles. In addition, the experimental results were compared with methods commonly adopted in current design practice including the nonlinear section analyses, shear strength models and effective width of the tension flange. The experimental data illustrate that the shear lag effect not only was not accurately accounted for by the effective width method but also significantly affected the strength and stiffness of the tested specimens.     

要特别重视古村落的保护——南漳漫云古村落的现状及保护探讨

南漳漫云古村落是全国第三次文物普查的新成果,其独特的景观价值、文化价值引起社会的广泛关注.其设计理念,建造方式体现了“天人合一”核心思想,具有浓厚的地域特色,是鄂西北建筑的代表.本文以南漳漫云古村落为例,对古村落的发展演变、结构布局、建筑特点以及保护现状进行分析和研究.并根据古村落的发展特点,探讨当前形势下南漳漫云古村落发展与保护.     

Window opening effects on structural behavior of historical masonry Fatih Mosque

Structural walls of old historical structures are either blind or have openings for functional requirements. It is well known that in and out of plane responses of structural walls are affected by the size, locations, and arrangements of such openings. The purpose of this investigation is to study the window opening effects on static and seismic behaviors of historical masonry old mosques. Fatih Mosque, which was converted from a church, constructed in 914 in Trabzon, Turkey, is selected for this purpose. The mosque is being restored. Structural exterior walls of the mosque were made using stone and mortar materials. When the plaster on the walls was removed during the restoration, 12 window openings were found as blind on the exterior structural walls of the mosque. Within the scope of restoration works, it is aimed to open such blind windows. In order to investigate the effects of the window openings on the structural behavior of the mosque, 3D solid and finite elements models of the mosque with and without window openings are initially developed. The experimental dynamic characteristics such as frequency, damping ratio, and mode shapes of the current situation of the mosque, where some windows openings are blind, are determined using Ambient Vibration Testing. Then, the finite element model of the current situation of the mosque is updated using the experimental dynamic characteristics. The static and seismic time history analyses of the updated finite element model with and without window openings are carried out. Structural behaviors of the mosque with and without window openings are compared considering displacement and stress propagations.     

Solitude or Performance? The Papal and Royal-Imperial Residences of Benedict XII and Charles IV in Avignon,Prague and Karlstein

A comparison of the architectural models applied, on the one hand, at the papal residence in Avignon (Benedict XII) and the royal and imperial residences in Bohemia (Charles IV) and, on the other, at the first forms of baronial apartment consisting of public (sala regia) and private rooms (studiolo; thalamus, locus) offers a new way of approaching this aspect of architectural history. The baronial apartment was a specific type of room in the residence and an early sign of the gradual transformation of the fortress architecture that had been associated with itinerant rule. Accordingly, it should be interpreted as one of the first example of the ‘state-building’ architecture used to construct fixed or temporary residential locations.     

单檐歇山式木构古建抵抗极端烈度地震试验调查研究

为更好地保护我国古建筑,基于《单檐歇山式古建筑抗震性能振动台试验》的相关成果,研究了强震作用下我国明清官式木构古建的抗震性能,制作了与该论文相同的试验模型,进行了振动台试验。通过对模型输入烈度逐渐增强的1940年El-centro波,并考虑地震波为水平双向作用,分析了强震作用下不同构造的试验现象,开展了详细的震后调查,获得了不同构造在强震作用下的抗震性能和震害机制。结果表明:强震作用下,我国明清官式木构古建的振动形式表现为柱架、斗拱、梁架及屋顶的近似同步往复摇摆;主要震害包括柱底偏移、榫卯节点开裂、拔榫、斗拱偏移及错位、额枋-垫板分离、墙体倒塌等,但承重木构架受损不严重,结构未产生倒塌。其良好抗震性能的原因与古建筑的构造特征密切相关。     

Uses of Gypsum in Spanish architectural heritage: Typologies and some unique construction techniques

ABSTRACT

In Spain, gypsum and its many typologies play an important role as a construction material in Spanish architectural heritage. Its historical use is mainly a direct consequence of the abundance of gypsum deposits and a constructive tradition which began in ancient times. In addition to being a sign of constructive identity, gypsum is a clear example of the strong link between traditional architecture and the natural resources of the territory. The aim of this article is after to identify gypsum deposits and gypsum architectural heritage found in different parts of Spain and to explain the different gypsum typologies—other than powdered gypsum—used. Finally, the most unique construction techniques are described, differentiating between structural elements, partitions, and enclosures, as well as architectural elements and surface finishes.