The need for conservation management in European 19th century urban housing

The prediction of the dynamic response of Unreinforced Masonry Structures (URMS) is a very complex task, since it is governed by material degradation and cyclic hysteric behaviour. Procedures based on nonlinear static analyses have been proposed for the seismic assessment of URMS, without properly considering hysteretic energy dissipation during the dynamic response. Even though dynamic nonlinear analyses provide satisfactory simulations of the seismic response, its application requires considerable computational effort and high user expertise for the accurate definition of the material properties, making it unsuitable for practical applications. However, simplified macro-element strategies, capable of simulating in-plane and outof-plane nonlinear responses, could represent a satisfactory engineering solution in the dynamic context. In this study the nonlinear static and dynamic in-plane behaviour of URMS was assessed by means of plane discrete models. The preliminary numerical investigation evidenced the need to define suitable hysteric constitutive laws for reliable nonlinear dynamic analyses of URMS.(undefined

Soil Settlement and Uplift Damage to Architectural Heritage Structures in Belgium: Country-Scale Results from an InSAR-Based Analysis

Soil movement may be induced by a wide variety of natural and anthropogenic causes, which are detectable in the local scale, but may influence the movement of the soil over vast geographical expanses. Space borne interferometric synthetic aperture radar (InSAR) measurements of ground movement provide a method for the remote sensing of soil settlement and uplift over wide geographic areas. Based on this settlement and uplift evaluation, the assessment of the potential damage to architectural heritage structures is possible. In this paper an interdisciplinary monitoring and analysis method is presented that processes satellite, cadastral, patrimonial and building geometry data, used for the calculation of settlement and uplift damage to architectural heritage structures in Belgium. It uses processed InSAR data for the determination of the soil movement profile around each case study, of which the typology is determined from patrimonial information databases and the geometry is calculated from digital elevation models. The impact on the historic structures is calculated from the determined soil movement profile based on various soilstructure interaction models for buildings. The resulting damage is presented in terms of a numerical index illustrating its severity according to different criteria. In this way the potential soil movement damage is quantified in a large number of buildings in an easily interpretable and user-friendly fashion. The processing of InSAR data collected over the previous 3 decades allows the determination of the progress of settlement- and uplift-induced damage in this time period. With the integration of newly acquired and more accurate data, the methodology will continue to produce results in the coming years, both for the evaluation of soil settlement and uplift in Belgium as for introducing related damage risk data for existing architectural heritage buildings. Results of the analysis chain are presented in terms of potential current damage for selected areas and buildings

Research on structural stability of the traditional timber houses in Bursa-Turkey

Bu çalışma, 13-15, Eylül 2016 tarihlerinde Leuven[Belçika]’ da düzenlenen 10th International Conference on Structural Analysis of Historical Constructions (SAHC) - Anamnesis, Diagnosis, Therapy, Controls Kongresi‘nde bildiri olarak sunulmuştur.Bursa has been exposed to many destructive earthquakes throughout the history; however, the traditional timber structural buildings are able to survive without significant damage until today. In this context, deteriorated, damaged and in good condition timber structure buildings which are located in various towns and villages of Bursa were examined in terms of construction systems, irregularities in plans and elevations, load bearing elements, cantilevers, material properties and the level of damages. In this study the researchers tried to find out the structural stability of these buildings by comparing their structural features obtained from the damaged and non damaged houses.As a result of the studies and investigations, it was observed that thanks to the system of using different joint techniques and wall bracing systems, the use of buttresses, capitals, metal connections, adobe in the design of timber structures, they have survived to the present day.KU Leuven, Raymond Lemaire Ctr ConservatArte ConstructoTrimbleCARMEUSELhoistVerstraete VanheckeMRT Grp MonumentABInBevKU Leuven, Civil Engn Dep

Cyclic fatigue of silica refractories – effect of test method on failure process

Silica refractories serving in high temperature industrial installations fail due to thermo-mechanical cyclic loads. The failure process was investigated by performing cyclic fatigue tests of several methods. In uni-axial compression the samples were tested either with constant force or displacement amplitude or with fixed upper displacement limit. In bending constant displacement amplitude tests were done. The investigation was supported by monotonic loading tests and microstructural analysis. It was determined that the fatigue failure occurs due to the degradation of interlocking in the crack wake. Cracking of larger grains is important for the crack initiation. The test set-up and the loading procedures significantly influence the potential to resist the crack propagation. Cyclic loading produces less brittle failure than monotonic loading. The displacement controlled method allows more gradual, less brittle, failure than the force controlled method. The potential of the crack arrest is less developed in bending than in compression.publisher: Elsevier articletitle: Cyclic fatigue of silica refractories – effect of test method on failure process journaltitle: Journal of the European Ceramic Society articlelink: http://dx.doi.org/10.1016/j.jeurceramsoc.2016.12.004 content_type: article copyright: © 2016 Elsevier Ltd. All rights reserved.status: publishe

Advanced techniques for monitoring of settlement-induced deformations and crack growth in historical masonry

In a search for novel, integrated and accurate monitoring techniques for crack measurements in masonry, five different techniques have been applied on a masonry wall during an experimental hree-point-bending test. The applied techniques were: optical fibres with distributed fibre Bragg grating sensors (FBGs), stereo-vision digital image correlation (DIC), optical fibre sensors for acoustic emission detection (AE-FOS), piezo-electric transducers for acoustic emission detection (AE-PZT) and LVDTs. While the latter two were applied as reference techniques, the former three were under investigation as novel application. A prerequisite for the selection of the novel techniques was their ability to be integrated within the masonry or to be applied as a non-contact technique. This paper focuses on the application of FBGs which were integrated within the masonry's bed joint and digital image correlation which was applied without the use of a speckle pattern. Both techniques proved applicable within the developed configuration and the highest sensitivity was observed for the integrated optical fibres with FBGs. In addition, the obtained experimental strain data were compared with numerical results from a meso model of the masonry wall. This study is part of a project which aims at combining remote and on-site monitoring techniques for risk assessment in historical masonry structures which are subjected to settlement-induced damage