TY - CONF A1 - Miccoli, Lorenzo A1 - Fontana, Patrick A1 - Ziegert, C. A1 - Müller, P. ED - Modena, C. ED - da Porto, F. ED - Valluzzi, M. R. T1 - Calibration of partial safety factors for earth block masonry under compression loading T2 - IB2MAC Brick and Block Masonry - Trends, Innovations and Challenges N2 - The goal of the present study is to assess the feasibility to develop a first reliable database of materials parameters for Earth Block Masonry (EBM). The database is crucial when defining the materials safety factors. In the first part an experimental campaign of compressive tests were carried out on two types of earth block and two types of earth mortar. The results showed that the mean variation of the compressive strength was remarkably less than expected. This low variation is related to a production with high quality standards of the materials employed. In the second part a partial safety factor for EBM under uniaxial compression was determined through the reliability method. The results proved the reliability of a common calculation method for EBM based on partial safety factors following the current standards. T2 - IB2MAC 2016 - 16th International Brick and Block Masonry Conference CY - Padua, Italy DA - 26.06.2016 KW - earth block masonry KW - partial safety factors KW - uniaxial compression test PY - 2016 SN - 978-1-138-02999-6 SP - 857 EP - 864 PB - CRC Press Taylor & Francis Group CY - London, UK AN - OPUS4-37145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ferraioli, M. A1 - Abruzzese, D. A1 - Miccoli, Lorenzo A1 - Mandara, A. ED - Galea, P. ED - Borg, R. P. ED - Farrugia, D. ED - Agius, M. R. ED - D'Amico, S. ED - Torpiano, A. ED - Bonello, M. T1 - Dynamic identification and seismic safety of two masonry towers T2 - Proceedings of the International Conference: Georisk in the Mediterrean and their mitigation N2 - The recent experience of Italian seismic events provided wide observational information about typical behaviour, damage patterns and intrinsic vulnerability of monumental buildings. Evidence indicates that historical constructions are by far the most vulnerable from the seismic point of view. As a consequence, they demand for the definition of urgent strategies for the protection of cultural heritage from seismic hazard. The main goal of an in-depth knowledge of the structure should help to avoid inadequate, unsuitable or dangerous rehabilitation operations, as well as to select non-invasive and reversible techniques for the best exploitation of material and technology features. The definition of reliable models and methods for seismic risk assessment of historical constructions is today a very important topic. Typical problems of masonry structures concern aspects like inherent structural lacks, material degradation, geotechnical problems, buckling behaviour of slender elements and dynamic loading vulnerability. Modelling the mechanical behaviour of masonry may play an important role, due to both inherent material complexity and great scatter in mechanical properties. Effective procedures for the identification of the structural parameters from static and dynamic testing are thus required. In particular, dynamic measurements may be very useful for the identification of mechanical properties and soil restraints and, consequently, for the calibration of advanced numerical finite element models. The paper addresses two case studies of structural monitoring and seismic assessment of medieval masonry towers in Italy: the bell tower of Aversa and the bell tower of Capua. These monuments, placed in the Campania region, were monitored by means of full-scale environmental vibration testing. Measured responses are then used for modal identification with a typical finite element model updating technique based on vibration test results. Parameters optimization is carried out on the basis of a criterion which minimises a weighted error on modal properties. A satisfactory improvement in the determination of modal parameters is thus obtained, resulting in a close agreement between the modal properties observed in dynamic tests and those calculated from numerical model. Seismic assessment is finally performed based on nonlinear static analysis of the tower under multimodal distributions of lateral loads. Results from nonlinear analysis indicate the potential collapse mechanisms and evidence dangerous structural weakness which may play a role in the seismic vulnerability of the towers. T2 - Georisk in the Mediterrean and their mitigation CY - Valletta, Malta DA - 20.07.2015 KW - masonry towers KW - ambient vibration tests KW - dynamic characterisation KW - seismic assessment PY - 2016 SN - 978-88-98161-20-1 SP - 250 EP - 251 PB - Mistral Service AN - OPUS4-37204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Fontana, Patrick A1 - Silva, N. A1 - Kocadag, R. A1 - Cederqvist, Ch. A1 - Krefft, O. A1 - Qvaesching, D. T1 - UHPC-AAC/CLC composite panels with self-cleaning properties. Materials and production technology T2 - Proceedings of Smart Facades Materials Conference 2016 N2 - The aim of this study is to show the development of a façade composite panel combining either an autoclaved aerated concrete or a cellular lightweight concrete insulation layer with a box-type external ultra-high performance concrete (UHPC) supporting layer. The paper presents the materials characteristics of the different components and the production technology of the panel. The efficiency of surface modifications of the materials forming the external shell of the panel is reported. The activation of self-cleaning properties is described. The test results showed that the most efficient way to use the water-repellent agent is its application on the substrate before the concrete cast. Concerning the production technology, the preliminary studies showed more advantages of a twostep manufacturing procedure of the UHPC boxes than a one-step procedure. T2 - Smart Facades Materials Conference CY - Wels, Austria DA - 24.02.2016 KW - facade composite panels KW - ultra-high performance concrete (UHPC) KW - autoclaved aerated concrete (AAC) KW - cellular lightweight concrete (CLC) KW - self-cleaning properties PY - 2016 SP - 1 EP - 14 PB - OÖ Energiesparverband CY - Wels, Austria AN - OPUS4-37185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ferraioli, M. A1 - Miccoli, Lorenzo A1 - Abruzzese, D. A1 - Mandara, A. T1 - Dynamic characterisation and seismic assessment of medieval masonry towers JF - Natural Hazards N2 - The paper investigates the dynamic characterisation, the numerical model tuning and the seismic risk assessment of two monumental masonry towers located in Italy: the Capua Cathedral bell tower and the Aversa Cathedral bell tower. Full-scale ambient vibration tests under environmental loads are performed. The modal identification is carried out using techniques of modal extraction in the frequency domain. The refined 3D finite element model (FEM) is calibrated using the in situ investigation survey. The FEM tuning is carried out by varying the mechanical parameters and accounting for the restraint offered by the neighbouring buildings and the role of soil–structure interaction. The assessment of the seismic performance of the bell towers is carried out through a nonlinear static procedure based on the multi-modal pushover analysis and the capacity spectrum method. Through the discussion of the case studies, the paper shows that the modal identification is a reliable technique that can be used in situ for assessing the dynamic behaviour of monumental buildings. By utilising the tuned FEM of the towers, the theoretical fundamental frequencies are determined, which coincide with the previously determined experimental frequencies. The results from seismic performance assessment through a pushover analysis confirm that the masonry towers in this study are particularly vulnerable to strong damage even when subjected to seismic events of moderate intensity. KW - masonry towers KW - ambient vibration tests KW - dynamic characterisation KW - seismic assessment PY - 2016 DO - https://doi.org/10.1007/s11069-016-2519-2 SN - 1573-0840 SN - 0921-030X VL - 86 SP - Suppl. 2, S489 EP - S515 PB - Springer AN - OPUS4-37187 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Miccoli, Lorenzo A1 - Drougkas, T. A1 - Müller, U. T1 - In-plane behaviour of rammed earth under cyclic loading: experimental testing and finite element modelling JF - Engineering Structures N2 - The purpose of this paper is to numerically simulate the in-plane behaviour of rammed earth walls under cyclic shear-compression tests. The experimental testing allowed obtaining the maximum horizontal loads, the displacement capacity and the level of non-linear behaviour of the respective loaddisplacement relationships as well as the failure modes. The calibration of the numerical model (finite element method) was carried out based on the experimental results. Within this framework, a micromodelling approach was considered. The behaviour of the rammed earth material was simulated using a total strain rotating crack model. A Mohr-Coulomb failure criterion was used to reproduce the behaviour of the interfaces between the layers. Although the numerical results achieved a satisfactory agreement with the experimental results a sensitivity analysis of the parameters involved was performed. The sensitivity analysis aimed at determining which parameters of the model have a significant impact in the model’s results. As expected the sensitivity analysis pointed out that the sliding failure occurrence is mainly influenced by two parameters of the interface elements: the interface tensile strength fit and the friction angle u. Moreover the cohesion c and the layers thickness showed a limited effect on the shear behaviour. It should be noted that the results mentioned above are related to the cases where a significant level of vertical compressive stress r is employed. KW - rammed earth KW - in-plane loads KW - shear behaviour KW - cyclic shear-compression tests KW - finite element modelling KW - pseudo-dynamic tests PY - 2016 DO - https://doi.org/10.1016/j.engstruct.2016.07.010 SN - 0141-0296 SN - 1873-7323 VL - 125 SP - 144 EP - 152 PB - Elsevier Ltd. AN - OPUS4-37165 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Miccoli, Lorenzo A1 - Fontana, Patrick A1 - Gardei, André A1 - Ziegert, C. A1 - Perrone, Ch. A1 - Kaiser, C. A1 - Gerrard, Ch. ED - Feiglstorfer, H. T1 - Analysis and diagnosis of earthen buildings: the case of Ambel preceptory in Aragon, Spain T2 - earth construction & tradition N2 - This study presents diagnostic techniques to assess the structural vulnerability of earthen buildings. Medieval structures at Ambel (near Zaragoza, Spain), once a preceptory or monastic house belonging to the Military Orders, provide a useful case study. After more than a thousand years of construction, failure and repair from the 10th century to the present day, Ambel preceptory today is characterised by marked inhomogeneities: construction materials and structural typologies are juxtaposed, with structural discontinuities at the interfaces between construction phases. This paper argues that, while static analysis is an essential prerequisite before a suitable maintenance program can be defined, no evaluation of the structural behaviour of any historic building can ignore an understanding of the building’s history. KW - historical earthen building KW - rammed earth KW - material characterisation KW - static monitoring PY - 2016 SN - 978-3-900265-34-2 VL - 1 SP - 201 EP - 229 PB - IVA-Verlag CY - Vienna, Austria AN - OPUS4-37076 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, U. A1 - Miccoli, Lorenzo A1 - Fontana, Patrick T1 - Development of a lime based grout for crack repair in earthen constructions JF - Construction and Building Materials N2 - The study presents the results from the development of a grouting material based on hydrated lime with addition of pozzolana, which is referred to as hydraulic lime, suitable for the repair of cracks in a variety of earthen building techniques. The goal was to develop a material also compatible with earthen structures exposed to dynamic loads. The grouting mortar was designed to be adaptable in strength properties and at the same time to have sufficient robustness for preparation and use on the construction site. Results showed a satisfactory performance of the grout concerning fresh and hardened mortar properties as well as injectability. KW - Earthen construction KW - Lime based grout KW - Cracks grouting KW - Rheology KW - Strength KW - Adhesion PY - 2016 DO - https://doi.org/10.1016/j.conbuildmat.2016.02.030 SN - 0950-0618 VL - 110 SP - 323 EP - 332 PB - Elsevier AN - OPUS4-37064 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Fontana, Patrick A1 - Silva, N. A1 - Kocadag, R. A1 - Cederqvist, Ch. A1 - Kreft, O. A1 - Qvaesching, D. T1 - UHPC-AAC/CLC composite panels with self-cleaning properties. Materials and production technology N2 - The aim of this study is to show the development of a façade composite panel combining either an autoclaved aerated concrete or a cellular lightweight concrete insulation layer with a box-type external ultra-high performance concrete (UHPC) supporting layer. The paper presents the materials characteristics of the different components and the production technology of the panel. The efficiency of surface modifications of the materials forming the external shell of the panel is reported. The activation of self-cleaning properties is described. The test results showed that the most efficient way to use the water-repellent agent is its application on the substrate before the concrete cast. Concerning the production technology, the preliminary studies showed more advantages of a two-step manufacturing procedure of the UHPC boxes than a one-step procedure. T2 - Smart Facade Materials Conference CY - Wels, Austria DA - 24.02.2016 KW - Facade composite panels KW - Ultra-high performance concrete (UHPC) KW - Autoclaved aerated concrete (AAC) KW - Cellular lightweight concrete (CLC) KW - Slef-cleaning properties PY - 2016 AN - OPUS4-37066 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Fontana, Patrick A1 - Ziegert, C. A1 - Müller, P. T1 - Calibration of partial safety factors for earth block masonry under compression loading N2 - The goal of the present study is to assess the feasibility to develop a first reliable database of materials parameters for Earth Block Masonry (EBM). The database is crucial when defining the materials safety factors. In the first part an experimental campaign of compressive tests were carried out on two types of earth block and two types of earth mortar. The results showed that the mean variation of the compressive strength was remarkably less than expected. This low variation is related to a production with high quality standards of the materials employed. In the second part a partial safety factor for EBM under uniaxial compression was determined through the reliability method. The results proved the reliability of a common calculation method for EBM based on partial safety factors following the current standards. T2 - IB2MAC 2016 - 16th International Brick and Block Masonry Conference CY - Padua, Italy DA - 26.06.2016 KW - Earth block masonry KW - Partial safety factors KW - Uniaxial compression test PY - 2016 AN - OPUS4-37067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Oliveira, D. V. A1 - Silva, R. A. A1 - Drougkas, A. A1 - Fontana, Patrick T1 - Numerical modelling of rammed earth under different in-plane load conditions T2 - Lehm 2016 - Proceedings of the 7th International Conference on Building with Earth N2 - The paper presents a comparison between two different numerical modelling approaches aimed to simulate the in-plain behaviour of rammed earth walls, namely under axial, diagonal and cyclic shearcompression loading. In the first part of the study the mechanical characterisation of wallets tested under uniaxial compression and diagonal compression and walls tested under in-plane cyclic shear-compression loading is presented. The results were used to implement and validate the finite element simulations. The numerical modelling of the rammed earth samples tested is then discussed in the second part. A non-linear constitutive law based on the total strain rotating crack model (TSRCM) was employed as implemented in the DIANA® software. The aim of the numerical analyses presented here is to simulate the behaviour of rammed earth under different inplane loading conditions. For the wallets, tests under static loading both macro- and micro-modelling approaches were considered for the simulation of the experimental tests. For the walls subjected to cyclic loading only the micro-modelling approach was applied for the simulation of the experimental tests. The respective FEM model was calibrated with the experimental results. The rammed earth layers were represented by continuum elements, the contact surfaces between layers by interface elements. This approach allowed assessing the influence of the apparent weakness of the interfaces between layers on the shear behaviour of rammed earth. The goal of the numerical simulation of the cyclic tests was to establish the adequacy of common analytical methods (e. g. used for masonry) applied to the analysis of rammed earth. Rammed earth exhibits brittle characteristics similar to masonry materials and is used in geometrical typologies, such as walls, common in masonry construction. T2 - Lehm 2016 - 7th International Conference on Building with Earth CY - Weimar, Germany DA - 12.11.2016 KW - Building materials KW - FEM analysis KW - Rammed earth KW - Compression and shear testing KW - Cyclinc loading KW - Failure mode KW - Crack pattern PY - 2016 SP - 1 EP - 9 PB - Eigenverlag Dachverband Lehm e. V. CY - Weimar AN - OPUS4-38820 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -