An Enhanced Finite Element Macro-Model for the Realistic Simulation of Localized Cracks in Masonry Structures: A Large-Scale Application

ABSTRACT

Finite element macro-modeling approaches are widely used for the analysis of large-scale masonry structures. Despite their efficiency, they still face two important challenges: the realistic representation of damage and a reasonable independency of the numerical results to the used discretization. In this work, the classical smeared crack approach is enhanced with a crack-tracking algorithm, originating from the analysis of localized cracking in quasi-brittle materials. The proposed algorithm is for the first time applied to a large-scale wall exhibiting multiple shear and flexural cracking. Discussion covers structural aspects, as the response of the structure under different assumptions regarding the floor rigidity, but also numerical issues, commonly overlooked in the simulation of large structures, such the mesh-dependency of the numerical results.     

Layers of religious and political iconoclasm under the Islamic State: symbolic sectarianism and pre-monotheistic iconoclasm

This article examines the heritage destruction undertaken by the Islamic State (IS) in Iraq and Syria. To date, their iconoclasm has been mostly characterised either as acts of wanton barbarism devoid of religious or political justification, or as a cynical performance designed as a mass media spectacle. Drawing on a systematic analysis of two key IS propaganda outlets – their on-line magazine, Dabiq, and the various slick films released by Al-Hayat – this article argues that the heritage destruction perpetrated by the IS are not only situated within a carefully articulated theological framework and key to the creation of a new and ideologically pure ‘Islamic State’, but that they are also constituted by several complex layers of religious and political iconoclasm. To demonstrate, this article documents the iconoclasm undertaken by the IS along two key axes: Symbolic Sectarianism (Shia and Sufi mosques and shrines); and Pre-Monotheistic Iconoclasm (ancient polytheistic sites). Attacks on key sites within these categories, such as the Sayyida Zaynab shrine in Damascus or the Mosul Museum, not only adhere to their religious and political framework but also serve broader geo-political agendas and are attacked as proxy targets for their physical and ideological opponents.     

Watermills: The Origin of the Use of Renewable Hydraulic Energy in Spain

The use of renewable hydraulic energy sources by mankind most likely has its origins in the development of the watermills. To understand the functioning of these mills, this article first reviews, through the analysis of different bibliographical sources, the technical evolution of the machinery used since the appearance of the first watermills to grind cereal grain in the 1st century bc.

Secondly, a particular area of the south-west of Spain, Alcalá de Guadaíra, has been selected for study, whose strategic location as well as its hydrological characteristics gave rise, firstly, to an intensive milling industry, and, later, a famed baking industry, from the late Middle Ages until recent decades. The huge development of these two industrial activities has made Alcalá de Guadaíra an exceptional example in Spain, with 40 watermills in the early 18th century.

Extensive work on site allowed the analysis of the state and types of watermills that still exist in this area, identifying their similarities and differences. Unfortunately, after they fell into disuse, only 28 of these mills remain today; 12 of them are in a relative good state of preservation, seven in an alarming state of ruin and, of the other nine, only some unrecognisable vestiges remain. Some of these mill buildings have been restored recently, although their machinery is missing. Only from old photographs or by visiting mills restored in other areas is it possible to determine how these watermills worked.

Due to the lack of financial resources to carry out physical restoration of the industrial heritage missing in these flour mills, a virtual model of one of them has been developed. This work provides, at least virtually, a reconstruction of the traditional mills which helps promote technological studies and shows how they worked, as part of virtual exhibitions. In addition, a computer application of augmented reality has been developed that any visitor can install on a mobile device to display the virtual reality of the machinery, generated by 3D models, so they can visualise the physical reality that they would have found in the mill.     

The Sound of Rock Art. The Acoustics of the Rock Art of Southern Andalusia (Spain)

This paper explores the potential of acoustics to interpret the prehistoric rock art of southern Andalusia (Spain). Tests undertaken in two areas, north of the Celemín river and the Bacinete area, will form the basis of our discussion. The results obtained at a selection of rock art sites show that the two key rock art sites, El Tajo de las Figuras and the large shelter at Bacinete, both with the majority of paintings in the earlier Laguna de la Janda style, had good resonance values. In contrast, at most of the other minor sites tested, the values for resonance were negative or insignificant, regardless of whether they were painted in Laguna de la Janda or schematic style. We conclude that the major rock art sites in southern Andalusia were chosen not only for their geological appearance and location in the landscape, but also for their acoustic properties.     

ZONING A CROSS‐BORDER CITY

This paper investigates zoning in a cross‐border linear city that consists of two bordering towns. In each town, a local regulator has a say in the location of the local firm. We find that local regulators may use zoning strategically. The incentive to gain consumers from the other town, or not to lose local consumers, may push regulators to approve only locations for firms close enough to the frontier. When zoning is costly an asymmetric equilibrium may emerge: only one regulator resorts to zoning. In the case of towns of different sizes, the regulator of the larger town is the only one that zones in an asymmetric equilibrium.     

A new elasmosaurid specimen from the upper Maastrichtian of Antarctica: new evidence of a monophyletic group of Weddellian elasmosaurids

O’Gorman, J.P. & Coria, R.A. September 2016. A new elasmosaurid specimen from the upper Maastrichtian of Antarctica: new evidence of a monophyletic group of Weddellian elasmosaurids. Alcheringa 41, xxx–xxx. ISSN 0311-5518

A new fossil elasmosaurid specimen, MLP 15-I-7-48, from the upper Maastrichtian Sandwich Bluff Member of the López de Bertodano Formation, Vega Island, Archipelago James Ross, Antarctica, is described. The fossil is a well-preserved anterior limb, which shares with Vegasaurus molyi from the upper Maastrichtian of Antarctica, a concave to flat anterior margin of the humeral shaft, and with Vegasaurus molyi and Aphrosaurus furlongi from the upper Maastrichtian of California, a well-defined depression on the anterior margin of the ventral surface of the humeral shaft. A phylogenetic analysis recovered MLP 15-I-7–48 as sister group of the lower Maastrichtian Vegasaurus molyi within a new clade nominated as Weddellonectia: Kawanectes lafquenianum ((Vegasaurus molyi; MLP 15-I-7–48) (Morenosaurus stocki (Aristonectinae))). This indicates that the previously proposed faunal turnover between the early and late Maastrichtian Weddellian marine reptile fauna, did not severely affect the non-aristonectine elasmosaurids. Additionally, other taxa previously considered evidence of a faunal turnover are re-evaluated.

José P. O’Gorman. [joseogorman@fcnym.unlp.edu.ar]. División Paleontología Vertebrados, Museo de La Plata, Universidad Nacional de La Plata, Paseo del Bosque s/n., B1900FWA, La Plata, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. Rodolfo A. Coria. [rcoria@unrn.edu.ar]. Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro—Subsecretaría de Cultura de Neuquén—Museo Carmen Funes, Av. CVórdoba 55 (8318), Plaza Huincul, Neuquén, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina.