TY - JOUR A1 - Miccoli, Lorenzo A1 - Müller, U. A1 - Fontana, Patrick T1 - Mechanical behaviour of earthen materials: A comparison between earth block masonry, rammed earth and cob N2 - Earth represents one of the oldest construction materials, which is still utilised both in developed and in developing countries. In this paper a comparison of the mechanical performance of structural elements built in three basic techniques, earth block (adobe) masonry, rammed earth and cob, is presented. In order to gain better knowledge on the structural behaviour under static loads an extensive compression and diagonal compression (shear) test campaign was performed. First compression results showed brittle mechanical behaviour in the case of earth block masonry and rammed earth elements, whereas cob exhibited a very different stress–strain pattern: cob can deform beyond the elastic range with a gradual drop in capacity. Despite its low compressive strength, cob thus presents a relatively good performance within the earthen material range as far as shear behaviour is concerned. The data here reported represents a base for a further investigation on the dynamic behaviour of the three materials considered. The study was carried out within the framework of the project NIKER funded by the European Commission dealing with improving immovable Cultural Heritage assets against the risk of earthquakes. KW - Earthen materials KW - Compression test KW - Diagonal compression test KW - Initial shear strength PY - 2014 U6 - https://doi.org/10.1016/j.conbuildmat.2014.03.009 SN - 0950-0618 VL - 61 SP - 327 EP - 339 PB - Elsevier Science CY - Amsterdam AN - OPUS4-30550 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Falchi, L. A1 - Müller, Urs A1 - Fontana, Patrick A1 - Izzo, F.C. A1 - Balliana, E. A1 - Biscontin, G. A1 - Zendri, E. T1 - Sustainability in the maintenance and protection of architectural surfaces: Innovative water-repellent pozzolana-lime mortars N2 - Water-repellent renders were studied in order to evaluate their suitability for restoration applications. Water repellent admixtures, such as powdered siloxane-based products and metal soaps (zinc and calcium stearates), were mixed with a pozzolana-lime binder similar to historical binders with hydraulic properties. The chemical-physical and structural properties, the effectiveness and the durability of the water-repellent mortars in different environmental conditions were studied. The influence of the water repellent admixtures was evaluated by FT-IR analyses, by testing the mechanical properties and the behaviour in presence of water. The durability of the water-repellent mortars was evaluated after the exposure to artificial weathering (UV-light and water) and to immersion/drying cycles in saturated sodium sulphate solution. The nature of the water-repellent admixtures influenced both the hydration reactions and the chemical-physical properties of the mortars resulting in different resistance to the weathering and to salt crystallization. T2 - Scienza e beni culturali XXX. 2014 - Quale sostenibilita' per il Restauro? CY - Brixen, Italy DA - 01.07.2014 KW - Water-repellent admixtures KW - Artificial weathering KW - Salt crystallization KW - Restoration mortars PY - 2014 SN - 978-88-95409-18-4 SN - 2039-9790 SP - 637 EP - 648 PB - Edizioni Arcadia Ricerche S.r.l. AN - OPUS4-31841 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Falchi, L. A1 - Müller, U. A1 - Fontana, Patrick A1 - Balliana, E. A1 - Zendri, E. ED - Charola, A.E. ED - Rodrigues, J.D. T1 - Artificial weathering of water-repellent mortars suitable for restoration applications N2 - The study evaluates Portland limestone cement mortars, natural hydraulic lime mortars and pozzolan-lime mortars modified with water-repellent admixtures (metal soaps and siloxanes) for their use in the maintenance of historic buildings. The chemical-physical characteristics, the durability and the resistance to artificial weathering (exposure to UV light and artificial rain) were examined. The exposure conditions used in the ageing test were chosen in order to simulate outdoor environmental conditions, in particular the processes caused by UV-light and thermal shock induced by rain water. T2 - Hydrophobe VII - 7th International conference on water repellent treatment and protective surface technology for building materials CY - Lisbon, Portugal DA - 11.09.2014 KW - Water repellent admixtures KW - Mortars KW - Portland limestone cement KW - Natural hydraulic lime KW - Pozzolana-lime KW - Artificial weathering PY - 2014 SN - 978-972-49-2270-6 SP - 123 EP - 132 AN - OPUS4-32138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Fontana, Patrick ED - Pena, F. ED - Chávez, M. T1 - Bond strength performances of anchor pins for earthen buildings. A comparison between earth block masonry, rammed earth and cob N2 - Connections improvement plays a key role in seismic upgrade of historical buildings. Their global response is related to the behavior of the single structural elements as well as to their mutual connections. Up to now only few data are available about the performance of grouted anchor pins in earthen materials where the critical point is the bond between the grout and the earthen substrate. In this paper, results of the experimental testing performed on earth block masonry, rammed earth and cob are presented. Pull-out tests were carried out to investigate the bond strength and failure modes of stainless steel rods with a lime based hydraulic grout and their compatibility with earthen materials. Rods with nuts were investigated to improve the pull-out capacity of the anchors. They showed higher pull-out capacity than rods without nuts. The performances of rods with nuts in cob were influenced by the rough surface at/of the earthen substrate. It is assumed that the non homogeneous surface caused an interlocking mechanism, which allowed to reach a pull-out capacity of about 54% higher than in earth block masonry. T2 - SAHC 2014 - 9th International conference on structural analysis of historical constructions CY - Mexiko City, Mexico DA - 14.10.2014 KW - Earthen materials KW - Pull-out tests KW - Anchor pins KW - Lime based hydraulic gout PY - 2014 SP - Paper-ID 07/011, 1-13 AN - OPUS4-32537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Fontana, Patrick ED - Lourenco, P.B. ED - Haseltine, B.A. ED - Vasconcelos, G. T1 - Bond strength of anchor pins for earth block masonry N2 - Connections improvement plays a key role in seismic upgrade of historical buildings. Their global response is related to the behaviour of the single structural elements as well as by their mutual connections. Up to now limited data is available on the performance of grouted anchor pins in earthen materials where the critical point is the bond between the grout and the earthen substrate. In this paper results of the experimental testing performed on earth block masonry are presented. Pull-out tests were carried out to investigate the bond strength and failure modes of stainless steel as well as glass fiber reinforced polymer (GFRP) rods with a lime based hydraulic grout and their compatibility with earth block masonry. GFRP rods were investigated as an alternative bonded-in anchorage material to the commonly used steel. In comparison with steel, they have a reduced weight and a reduced coefficient of thermal expansion. Their lower modulus of elasticity seems to be more compatible with the modulus of elasticity of earthen materials, although they exhibit a brittle fracture with lack of plastic phase. T2 - 9th IMC - International Masonry Conference CY - Guimaraes, Portugal DA - 07.07.2014 KW - Earth block masonry KW - Pull-out tests KW - Anchor pins KW - Lime based hydraulic grout KW - Pull-out testing PY - 2014 SN - 978-972-8692-85-8 SP - Paper ID 1623, 1 EP - 12 AN - OPUS4-31139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schroeder, H. A1 - Ziegert, C. A1 - Fontana, Patrick ED - Lourenco, P.B. ED - Haseltine, B.A. ED - Vasconcelos, G. T1 - The new German standards for earth blocks and earth masonry mortar N2 - In August 2013, the German National Institute for Standardization DIN published three national standards for industrially-produced earth building materials without the use of chemical stabilizers: DIN 18945 Earth blocks – definitions, building materials, requirements, test procedures DIN 18946 Earth masonry mortars – definitions, building materials, requirements, test procedures DIN 18947 Earth plaster mortars – definitions, building materials, requirements, test procedures The development of these standards was initiated by the Dachverband Lehm e.V. (DVL), the German umbrella organisation for building with earth. These standards are in accordance with the requirements of the EU Regulation No. 305/2011 which came into force in Germany on 1 July 2013. These basic requirements introduce provisions relating not only to the safety of buildings and other construction works but also to health, durability, energy economy, protection of the environment and other important aspects in the public interest. The basic requirements are defined by essential characteristics expressed by levels or classes, or in a description. The relevant essential characteristics define the performance of the construction product. The DIN 18945, 46 and 47 outline unified test procedures describing the relevant essential characteristics of the earth building products as well as systems for assessing and verifying the constancy of their performance. The relevant systems of verification are determined by a national Technical Assessment Body (TAB), which in Germany is the Deutsches Institut für Bautechnik DIBt. T2 - 9th IMC - International Masonry Conference CY - Guimaraes, Portugal DA - 07.07.2014 KW - DIN norms KW - Germany KW - Earth blocks KW - Earth masonry mortar KW - Earth plaster mortar KW - Standards KW - Earth block masonry KW - Earth mortar PY - 2014 SN - 978-972-8692-85-8 SP - Paper ID 682, 1 EP - 10 AN - OPUS4-31140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miccoli, Lorenzo A1 - Garofano, A. A1 - Fontana, Patrick A1 - Müller, U. ED - Lourenco, P.B. ED - Haseltine, B.A. ED - Vasconcelos, G. T1 - Static behaviour of earth block masonry: experimental testing and finite element modelling N2 - In this paper an extensive research campaign aimed to define the mechanical performance of earth block masonry panels is presented. Uniaxial compression and diagonal compression tests were performed. The test results confirmed the brittle behaviour of earth block masonry under uniaxial compressive load and showed that the failure of earth block masonry under shear load occurs by sliding of the earth blocks along the mortar joints after initial cracking in mortar joints and earth blocks. For diagonal compression test results showed that building technique practice is one of the key factors affecting the structural performances. Experimental behaviour was modelled with a non-linear model capable of describing cracking behaviour. Both micro-modelling and macro-modelling implementing isotropic or orthotropic material laws were used to assess the reliability of different modelling strategies. The model calibration was carried out by sensibility analysis of the input parameters to understand the influence of unit strength on the shear behaviour of masonry. T2 - 9th IMC - International Masonry Conference CY - Guimaraes, Portugal DA - 07.07.2014 KW - Earthen materials KW - Compression test KW - Diagonal compression test KW - Numerical modelling KW - Earth block masonry KW - Uniaxial compression test PY - 2014 SN - 978-972-8692-85-8 SP - Paper ID 1484, 1 EP - 14 AN - OPUS4-31138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -