Masonry Italian Code-Conforming Buildings. Part 1: Case Studies and Design Methods

ABSTRACT

Several architectural configurations of unreinforced masonry residential buildings are designed according to the different methods proposed in the Italian code: rules for the so-called simple masonry buildings, linear and nonlinear static analyses. Always complying with code requirements, for each building-site combination, the design was made, as much as possible, without an excessive margin of safety. The different design methods provided buildings with very different levels of safety, being linear static analysis largely overconservative with respect to the nonlinear static approach. These buildings were then analyzed in the companion paper.     

Survey and Experimental Investigation of Movable Fire Loads in Japanese-Style Wooden Historical Buildings

ABSTRACT

This study investigated the movable fire loads and the characteristics of combustible materials in Japanese-style wooden historical buildings via field surveys and cone calorimeter experiments. Twenty-one historical buildings with 102 rooms and a total floor area of 2235.06 m² were surveyed to determine the movable fire load. Strong correlations among fire load density, compartment floor area, and spatial use are found in this survey. The mean values of the movable fire load density in decreasing order in terms of room use are storeroom (431.38 MJ/m²), study room (298 MJ/m²), bedroom (294.88 MJ/m²), reception room (287.20 MJ/m²), and dining room (217.11 MJ/m²), providing fire engineering design with a reliable fire load setting in various types of rooms in historical buildings.     

Seismic Assessment of the Lima Cathedral Bell Towers via Kinematic and Nonlinear Static Pushover Analyses

ABSTRACT

The protection of cultural heritage against earthquake induced actions is one of the main challenges the earthquake engineering science and practice are facing. This article presents a seismic assessment study on one of the most ancient colonial buildings present in Peru, the Cathedral of Lima, focusing on its towers. A historical review highlighted how these structures, together with the whole Cathedral, suffered intense damage and partial collapse during previous earthquakes. In order to identify the structure main deficiencies, both linear kinematic analyses and nonlinear static analyses have been performed. Different nonlinear finite element models have been created to evaluate the influence of the adjacent walls. Different load distributions have been compared to evaluate how simplified patterns could provide results close to load distributions taken from a modal analysis of the complex. A simple retrofit strategy, consisting on the introduction of steel ties, has also been studied as a reference. Results show good correlation between kinematic and pushover analyses. The construction, when compared to the requirements of the national code for new buildings, results significantly vulnerable, pointing out the need to accept some structural damage even after seismic retrofit.     

Issues in Urban Industrial Conservation: The Nottingham Lace Market

Abstract

The preservation of industrial buildings of historic interest is of prime importance to the industrial archaeologist. Yet many of these buildings are to be found within the heart of the great manufacturing cities. How are they to be conserved alongside the built environments within which they were originally set? This article takes the Nottingham Lace Market, which contains some of the finest examples of nineteenth century industrial buildings, and addresses itself to the question of how various public agencies have attempted to make the area economically viable in order to facilitate conservation and preservation work.     

Evaluation of 2D Seismic Site Response due to Hill-Cavity Interaction Using Boundary Element Technique

This paper deals with the evaluation of two-dimensional site-effects due to the seismic interaction between hills with various configurations and underground cavities. The time-domain boundary element method is used to evaluate the site-effects of hill-cavity interaction subjected to vertically propagating in-plane SV and P waves. The presence of an underground cavity and the hill topography are expected to induce significant effects on the surface ground motion. To further examine the contribution of the amplification ratio of the hill-cavity system, a fairly simple approach, which can compute the response spectra of the hill’s surface motion above a cavity based on the real input motions, is also used to input motions.     

Simulation Of Shake Table Tests on Out-of-Plane Masonry Buildings. Part (II): Combined Finite-Discrete Elements

ABSTRACT

Out-of-plane response of unreinforced masonry elements is frequently the most critical aspect of the seismic performance of existing masonry buildings. The response of such elements is usually governed by equilibrium rather than strength. Hence, it is customary to resort to rigid-body models, accounting for possible rotations, and/or sliding. However, the results of such analyses depend on the initial choice of the mechanism. In this article, the shaking-table experiments on a brick-masonry specimen, and on a stone-masonry specimen have been modeled by resorting to a combined finite-discrete element strategy. Despite the coarse discretization of both discrete and finite elements, the three-dimensional models are able to capture the experimentally observed multi-degree-of-freedom mechanisms, without any a priori assumption on the mechanism. A sensitivity analysis is carried out, addressing eight different parameters. The identification of the mechanism is sufficiently robust, but the assessment of its activation and failure is best done by combining the finite-discrete element model with a simplified model of the recognised mechanism.     

Long-term agrarian landscapes in the Troodos foothills,Cyprus

We investigate the temporal and environmental relationships between the terraced hill slopes of Politiko-Koloiokremmos and the adjacent Bronze Age settlement of Politiko-Troullia in foothills of the Troodos Mountains, central Cyprus. Mapping of 102 stone walls on Koloiokremmos is compared with 66 walls farther afield on Cyprus to create a six-part terrace typology. Sherd counts from 174 2-m radius collection circles over approximately 20 ha on Troullia and Koloiokremmos were used to create interpolated sherd density surfaces revealing distinctly different patterns of land use for four major archaeological eras between the Cypriot Bronze Age and Medieval Period. We compared sherd density patterns according to terrace types, length, slope and vegetation cover determined by SAVI (Soil-Adjusted Vegetation Index) from Ikonos and Quickbird satellite imagery.The most robust sherd patterning indicates Prehistoric Bronze Age settlement at Troullia, as confirmed by soil resistivity and excavation, and multi-period land use on Koloiokremmos immediately upslope of the village that may be associated with agricultural terracing. Scattered sherd concentrations indicate later use of this landscape as an agricultural hinterland for the Iron Age city of Tamassos. Sherds and a down slope spread of roof tiles from the Roman through Medieval periods suggest an isolated structure near the crest of Koloiokremmos. Longer terraces correlate with greater vegetation cover and are interpreted as agricultural, while shorter terraces, apparently for erosion control and arboriculture, are significantly related to Prehistoric Bronze Age sherd patterns. Our results suggest that coordinated analysis of archaeological, geographical and remotely sensed environmental data associated with terraced landscapes can be used to infer long-term patterns of agricultural land use.     

Skating Rinks to Shadow Factories: the Evolution of British Aircraft Manufacturing Complexes

Abstract

This article provides a broad analysis of the development of the British aircraft industry and the factories that it has occupied. Particular attention is given to the use of second-hand buildings, the way in which sites and structures have been adapted, and the importance of investment during the two world wars and links with car manufacturers.     

Experimental Study of Large Area Suspended Ceilings

Damage of nonstructural components during past seismic events was shown to be not only a critical threat to life safety in extreme cases but also led to substantial reduction of functionality of buildings and other facilities. Because of the complex construction of nonstructural and architectural components, current standards provide only limited guidance for the seismic design. Suspended ceiling systems are among the less understood important nonstructural/architectural components in buildings for which design standards provide limited guidance. To understand the dynamic behavior of suspended ceiling systems, a series of full scale shake table tests of 20 ft × 53 ft and 20 ft × 20 ft ceiling systems were conducted at the Structural Engineering and Earthquake Simulation laboratory (SEESL) at University at Buffalo (UB). For the full scale dynamic testing, a new test frame providing a continuous suspended ceiling area of 1,060 ft² was constructed on the tandem shake tables and was equipped with an open-loop shake table compensation procedure. The combined designs of the physical frame and of the shake table motion controllers allowed simulating the required floor/roof motion according to ICC-ES AC156 standard at the roof of the test structure. Various test configurations were selected in order to determine the influence of different system conditions and the effects or efficiency of various protective systems required by the current standard ASTM E580 for seismic design. Based on the test data and the failure mechanisms observed, damage states are defined, and fragility curves are developed. The results of the fragility analysis show that a ceiling system becomes more vulnerable as (a) it is subjected to multi-directional input motions, (b) heavier tiles are installed, (c) the size of a ceiling area increases, and (d) lateral restraints are not installed. In addition, simplified numerical models that can capture the special behavior of ceiling systems are developed and presented in a companion paper. This paper presents the experimental study of large area suspended ceiling systems involving test setup and configurations, test motions generated by a unique control system, and basic lessons gained from the experiments.     

Seismic Assessment of a Monumental Building through Nonlinear Analyses of a 3D Solid Model

ABSTRACT

The paper analyzes the static behavior and the seismic vulnerability of the “San Francesco ad Alto” building in Ancona (Italy), which is currently used as a Regional Headquarter of the Marche Region by the Italian Army and was formerly a monastery. The global static structural behavior and the dynamic properties have been evaluated using the Finite Element modeling technique, in which the nonlinear behavior of masonry has been taken into account by proper constitutive laws. The concepts of homogenized material and smeared cracking are used to evaluate the capacity of the monastery to withstand lateral loads together with the expected demands resulting from seismic actions (N2 method), using a nonlinear static analysis (pushover). The comparison of seismic demand and capacity confirms the susceptibility of these types of buildings to extensive damage and collapse, as frequently observed in similar buildings. This paper aims to point out that advanced numerical analyses can offer significant information on the understanding of the actual structural behavior of historical buildings. It is believed that the methodology and the overall conclusions of this case study are valid for many historical monasteries in Europe.     

Experimental and Analytical Investigation on the Corner Failure in Masonry Buildings: Interaction between Rocking-Sliding and Horizontal Flexure

ABSTRACT

The failure mechanism of corners in masonry buildings has frequently been observed in seismic scenarios, but only a few works and no experimental investigations devoted to it are available in the literature. In this aritcle, the experimental behavior of a simple masonry corner is first analyzed, by simulating the seismic horizontal actions through a progressive tilting of the supporting base. Then, the conditions of the onset of two possible failure modes are analytically formulated: they are the rocking-sliding and the horizontal flexure mechanism. A three-dimensional macro-block model with frictional joints is used to analyze these mechanisms, while the crack patterns and the load factors are derived through the kinematic approach of the limit analysis. The evaluation of the in-plane frictional resistances involved by the rocking-sliding mechanism is performed by applying a reliable criterion previously proposed, while for the torsion strength involved in the horizontal flexure mechanism, simplified yield conditions are adopted and a possible criterion is also introduced to take into account the actual reduction of the contact surfaces. Last, the experimental findings are compared and critically interpreted in light of the analytical results and the influence of the main parameters on the prevailing mechanism is highlighted.     

The Excavation of a Brick Clamp at Shotesham St. Mary,Norfolk, 1969

Abstract

Rescue excavations in the small village of Llanmaes investigated an area of earthworks indicating the presence of several buildings. Medieval evidence was largely confined to finds. Three late 17th-century properties were examined; it is possible that they represent a planned development on the east side of the village green in response to population expansion in the Vale of Glamorgan. The buildings are of simple two-roomed plan, and would appear to be tenements of low status. One of the buildings produced evidence of smithying. A large group of metal finds of agricultural and domestic use was found, as was a closely-dated assemblage of wine bottles; a large midden deposit on the north edge of the site contained a very large group of post-medieval pottery. The buildings were abandoned by the end of the 18th century, presumably following rationalization of the local settlement morphology and farming. Thus the site represents a short-lived expansion in low-status rural housing at the time of the ‘Great Rebuilding’.     

Seismic Evaluation of Tall Buildings Using a Simplified but Accurate Analysis Procedure

A simplified analysis procedure for evaluating the nonlinear seismic responses of tall reinforced concrete (RC) buildings is examined in this study. It is called the Uncoupled Modal Response History Analysis (UMRHA) procedure. It can be viewed as an extended version of the classical modal analysis procedure, where the nonlinear response of each vibration mode is first computed, and they are later on combined into the total response of the structure. The procedure requires the knowledge of the modal hysteretic behavior, which can be obtained from a cyclic modal pushover analysis. The responses of four tall buildings in Bangkok to distant large earthquakes are computed by this procedure and compared with those obtained from the Nonlinear Response History Analysis (NLRHA) procedure. These four buildings have different heights—varying from 20 to 44 stories, different configurations of floor plan, and different arrangement of RC walls. The comparison shows that the UMRHA procedure is able to accurately compute the story shears and story overturning moments, floor accelerations, and inter-story drifts of all these tall buildings. The required computational effort is also extremely low compared to that of the NLRHA procedure. Moreover, since the UMRHA procedure computes the response of each individual vibration mode, it provides more understanding and insight into the complex nonlinear seismic responses of these tall buildings.     

Seismic Vulnerability of Historical Masonry Aggregate Buildings in Oriental Sicily

ABSTRACT

The seismic vulnerability assessment of historical UnReinforced Masonry (URM) buildings is a very complex task since it is strongly related to a great variety both of geometrical layouts and of masonry mechanical characteristics. In this article, some results of a Catania University research project, denomined “FIR 2014”, focused on the seismic vulnerability estimation of historical buildings, built in Catania after the 1963 earthquake, are presented. First, a detailed typological analysis of the considered urban fabric, characterized by typical residential masonry buildings, has been performed. Such analysis allowed recognizing an elementary structural modulus, which has been studied according to different geometrical layouts representative of isolated or aggregate buildings. The results of nonlinear static analyses, performed by applying an innovative macro-element approach, allowed for the assessment the seismic vulnerability of typical URM buildings coherently to the Italian seismic code. The adopted macro-element strategy for the seismic assessment of aggregate masonry buildings, although related to a specific historical center, may be applied to similar urban fabrics and can also be used for the calibration and validation of fast seismic assessment strategies, particularly useful for the evaluation of the seismic risk at urban scale.     

British Assessments of Tipu Sultan’s Hill Forts in Northern Mysore, South India, 1802

Hundreds of early modern forts dot the South Indian landscape, but more is known about their art-historical aspects than how these fortifications were built, maintained, and used. The latter aspects are examined in a comparative analysis of six Mysore hill forts, using East India Company surveys that were prepared in 1802 shortly after British forces took command of these installations from Tipu Sultan’s garrisons. These highly detailed inventories show that the hill forts were poorly maintained, inadequately supplied, contained relatively few garrison buildings, and, from the British perspective at least, were inadequately armed to mount a successful defense. At the turn of the century, these forts were functionally obsolete, ill prepared to serve as supply depots, and strategically valuable only to quiet local populations and deny the use of such places to potential enemies.     

The 18th-Century Baraccato of L’Aquila

ABSTRACT

This article attempts to describe a particular form of baraccata house, found in L’Aquila, Italy. The differences between this form of baraccato and the Italian traditional timber-framed (T-F) structures, the baraccato borbonico and the baraccato alla beneventana, are shown. In the upper valley of the Aterno river (Abruzzo, Italy), a few kilometers far from L’Aquila, wonderful 18^th-century examples of T-F masonry structures are present. The use of wood pervades both the poor and noble buildings. In this article, the documentary and functional features of this peculiar anti-seismic timber-based building technique, which is widespread in L’Aquila and the neighboring areas, is described. After a comparative analysis of the technique’s features, the case of three T-F buildings, belonging to three different social classes is reported, the first is the Ricci palace in Mopolino di Montereale, the second is a middle-class building, and the third is a rural one. The 1703 earthquake, which affected the upper valley of the Aterno river and the nearby city of L’Aquila, gave rise to an ante litteram anti-seismic culture. Timber was not seen as an obstacle to durability but a material to be exploited to protect buildings from earthquakes.     

The conservation and management of mudbrick buildings at Tell Qasile,Israel

Abstract

Tell Qasile, in the area of the Eretz Israel Museum in north Tel Aviv, is the location of a small town founded in the twelfth century BCE. The site has significant importance for the study of various aspects of the Iron Age period in Israel. The buildings at the site were constructed of mudbricks on stone foundations. Conservation of buildings at the site was carried out using three methods: 1) building roofs (in roofed areas no other conservation was needed); 2) conserving mudbrick walls by plastering them in modern plaster made up in imitation of ancient building material; 3) full restoration of buildings up to roof level (carried out in one case). These methods were successful, and, due to the location of the site within a large museum compound, it is utilized for archaeological education, mainly of schoolchildren.     

A Novel Procedure for Simplified Nonlinear Numerical Modeling of Structural Units in Masonry Aggregates

ABSTRACT

Historical centers are always composed of masonry building aggregates often designed without respecting seismic design criteria. The current seismic Italian code does not foresee a clear calculation method to predict their static nonlinear behavior. For this reason, in this article the seismic response of structural units into masonry aggregates has been predicted through a simplified modeling approach. The implemented procedure has been calibrated on the results of a numerical model performed by using the Equivalent Frame Method (EFM), implemented within a Finite Element Method (FEM) calculation program, used to investigate a basic building compound representative of the constructive techniques developed in the past decades in the Southern Italy.

First, the whole aggregate has been modeled and analyzed in the nonlinear static field in order to evaluate the seismic behavior of both intermediate and head structural units.

Later on, the seismic response of these structural units, considered as isolated structures, has been assessed by considering in simplified way their position in the aggregate, as well as the influence of other constructions.

Finally, the achieved results on the above single analysis cases have been compared with those deriving from the investigation of the whole building compound, allowing to confirm the effectiveness of the proposed novel analysis procedure.     

Seismic vulnerability assessment of historic centers: description of a predictive method and application to the case study of scanno (Abruzzi,Italy)

ABSTRACT

In this article, a predictive model for the seismic vulnerability assessment of old Italian historic centers is presented through its direct application to a meaningful case study, the historic center of Scanno, in Abruzzi, Italy.

The proposed method is calibrated on the basis of the observations carried out on similar historic centers hit by the 2009 L’Aquila earthquake and is applied in order to provide likely damage scenarios by means of fragility curves. The method is based on the evaluation of a limited number of structural and typological parameters that can be obtained by simple and rapid inspections on buildings. In addition, it is conceived in order to provide useful information on the most effective anti-seismic strategies to be implemented on urban scale for pursuing a global mitigation of the seismic risk and for the application of suitable risk reduction policies.

The final aim of the article is to give an applicative vision of the method, by providing instructions on how to judge the features of the buildings that are influential on their seismic behavior, as well as by showing the potentiality of the method itself in providing likely damage scenarios, also with the support of GIS-based representations.     

FREIGHT-HANDLING TECHNOLOGIES AND INDUSTRIAL BUILDING DESIGN: FREIGHTHOUSE AND WAREHOUSE FACILITIES OF THE CHICAGO JUNCTION RAILWAY, 1900–30

Abstract

Among the first US railway companies to use the electric tractor and elevator in freight-handling buildings, the Chicago Junction Railway (CJR) primarily served industries in the rapidly growing Central Manufacturing District. CJR freight-handling services were initially provided in single-storey, and subsequently multi-storey, brick and mill buildings, using hand trucks, with only limited storage and warehousing space available. Labour cost savings, and changes in the scale and flexibility of freighthouse operations, possible with the electric tractor and elevator, allowed the CJR to meet the demand for increased freight-handling and warehousing capacity by augmenting older facilities with multi-storey, integrated freighthouse and warehouse buildings, latterly built with steel-reinforced concrete.