Probabilistic life-cycle assessment and rehabilitation strategies for deteriorating structures: a case study

When it comes to existing buildings, the estimation of the structural residual bearing capacity is required to evaluate the potential for reuse/conversion. The level of detail and accuracy of surveys dramatically affect structural diagnostics. In order to optimise the experimental survey process, a simulation of the structural life-cycle may be useful.

Based on a previously developed approach of Monte Carlo simulation implemented with a damage law for the life-cycle analysis of newly designed constructions, this paper presents the method application to a historic roof steel structure. It aims to identify critical situations, assess the residual life of the system, and plan possible retrofit strategies for the building conversion.

The case study is a steel frame roof structure of the ex pig abattoir within the complex of the municipal slaughterhouse in Monza (close to Milan, Northern Italy) and protected from the Cultural Heritage Authority. The life-cycle of the structure is here investigated over different stages of the building lifespan along with the damages caused by aging and negligence. The construction was built in 1902, and abandoned in 1984. Therefore, the periods analysed are: from construction to disuse and from disuse to today. The second phase of life, still on going, has significantly sped up the degradation.

The probabilistic evaluation of failure times is discussed and the possible interventions scenarios in terms of costs, and after-maintenance reliability and safety are investigated.     

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.     

Building survey forms for heterogeneous urban areas in seismically hazardous zones. Application to the historical center of Valparaíso,Chile

ABSTRACT

Building survey is an essential data-collection procedure to feed large-scale seismic vulnerability assessment. The available strategies usually consider survey forms to gather information about the urban buildings. The application of the available survey forms poses important challenges for the case of the heterogeneous urban centers including different structural typologies. This work proposes four specific survey forms for traditional structural typologies constructed with masonry, reinforced concrete, mixed steel-reinforced concrete, and timber. The proposed forms request essential information on the parameters necessary for seismic vulnerability assessment, by evaluating the lateral-load resistant system, regularity, condition of conservation, and existing damages. The survey forms were applied to the study of 111 buildings of the historical center of Valparaíso, Chile. The proposed methodology was complemented with the use of Geographic Information Systems to obtain a complete database with the structural characterization of the most representative typologies for future works of large-scale seismic vulnerability assessment.     

Biodiversity Conservation: The Process of Economic Assessment and Establishment of a Protected Area in Vanuatu

This article describes the framework adopted for the socio-economic assessment of protected areas intended to safeguard biodiversity. This framework, which can be described as a three-tiered approach to conservation, is applied to the process of assessment and establishment of a protected area (PA) in Vanuatu. The potential benefits that the landowners of the PA could derive from logging activities, and the subsistence values derived from the PA are considered. It appears that if the PA was to be established without the payment of any compensation, the landowners would face substantial net costs. During the research process, it was suggested that the Government of Vanuatu could take up a lease on the land to compensate the landowners for the loss of potential logging royalties. When the benefits accruing to the landowners from a lease agreement are compared with the foregone logging royalties, it is found that the net present value of a seventy-five year lease agreement is approximately equivalent to the net present value of logging royalties.     

When megaprojects meet archaeology: a research framework and case study from Yenikapi,Istanbul

From 2004 to 2012, 37 well-preserved Byzantine shipwrecks were discovered during construction of two underground train stations at Yenikap?, Istanbul. Despite its complexity, archaeology is rarely studied through organisational and management lens. This paper investigates the Yenikap? rescue excavations using two innovative analytical frameworks for archaeology – the Heritage Chain and Structure Conduct Performance analysis – which highlight the crucial but too often overlooked role of practices (or emerging strategies) in public policy, helping identifying strengths and weaknesses of the project. In this sense, two elements of the system seem fundamental: its extreme centralisation and its ongoing process of decentralisation. The research, based on a phenomenon-driven approach to management of archaeological and cultural heritage projects, highlights how Turkey’s uncertain legal environment for rescue archaeology led to emergent, ad hoc management and funding solutions that mixed state and private involvement in novel ways through a multi-level outsourcing.     

Prefiguring a future city: urban growth,spatial planning and the economic local context in Catalonia

This study undertook a quantitative analysis of town master plans to define future urban growth. Spatial direction and intensity of urban expansion were analysed in relation to local contexts using land zoning and a comprehensive database of socio-economic indicators at the municipal scale in Catalonia, Spain. Our results illustrate a progressive shift towards discontinuous settlements consolidating urban centres in most accessible rural areas. Contrary to what was hypothesized (and partly observed) in recent decades, settlement expansion will modestly contribute to a balanced urban spatial structure. Future urban development in Catalonia will not follow a polycentric model, fuelling instead the growth of medium and small urban centres. This process may consolidate the incipient divide in rural areas with high accessibility and a dynamic economic base with remote inland areas experiencing land abandonment and depopulation. The use of indicators derived from town master plans in the assessment of (scattered or polycentric) future urbanization in Europe is finally discussed.     

Palaeolithic engravings and sedimentary environments in the Côa River Valley (Portugal): implications for the detection,interpretation and dating of open-air rock art

The pre-Magdalenian phase of the Côa River Valley open-air rock art is mostly distributed at the boundary between the rocky valley slopes and the floodplain that correspond to the most favourable geomorphological setting for the preservation of pecked and deeply superposed engravings of the most famous artistic phase of the area. The natural vertical panels of the engraved art located at this geomorphological interface have suffered weathering during two cold events of the Lateglacial. They were buried by several colluvial and alluvial deposits. The reconstruction of the sedimentary and archaeological context of the CôaRiver Valley engraving permits a better assessment of the preservation processes and interpretation of Palaeolithic open-air rock art.     

‘A wonderful city of palms and dates’: Salamis-Constantia in transition from Late Antiquity to the early Middle Ages (ca. 600–ca. 800 CE)

The article focuses on Salamis-Constantia, the political and ecclesiastical capital of the island of Cyprus, from the 360s to the tenth century, marking the passage from Late Antiquity to the early Middle Ages. The aim here is to debunk the historiographical model proposed for interpreting the declining fortunes of Cypriot urban sites, while at the same time applying the category of transition in order to explain the changes experienced in the local economic life, material culture and socio-political structures.